Can Diet Change the Gut Microbiome in Pulmonary Fibrosis?

Can What We Eat Influence the Gut–Lung Axis?

Yes.

Among all environmental factors that influence the intestinal microbiome, diet is one of the most powerful and modifiable.

What we eat determines which substrates reach intestinal microorganisms.

Those microbes then convert dietary components into hundreds of metabolites capable of interacting with:

• intestinal epithelial cells

• immune cells

• metabolism

• distant organs

The lung is one of those organs.

This has created interest in whether dietary modification might influence pulmonary fibrosis through the gut–lung axis.

The scientifically accurate answer is:

Diet can clearly change aspects of the gut microbiome.

What has not been demonstrated is that a microbiome-directed diet can stop or reverse human pulmonary fibrosis.

What Does the Human Diet–Microbiome Evidence Show?

A 2026 systematic review evaluated 80 controlled clinical trials examining dietary interventions and gut microbiota.

The review included Mediterranean, plant-based, high-fiber, ketogenic, gluten-free, Western, Japanese, Korean, low-FODMAP and other dietary patterns.

Dietary interventions altered microbial taxa and metabolic markers, although changes in overall alpha and beta diversity were inconsistent.

Mediterranean, high-fiber, plant-based, high-polyphenol and several traditional dietary patterns tended to increase SCFA- or lactic-acid-producing bacteria or reduce opportunistic organisms.

In contrast, Western, animal-based, ketogenic, gluten-free and low-FODMAP dietary patterns were associated in some studies with reductions in SCFA-producing organisms. (PubMed⁠)

This confirms an important principle:

food changes microbial function.

But Has Diet Been Proven to Change IPF Outcomes Through the Microbiome?

No.

There are currently no large randomized clinical trials demonstrating that a microbiome-targeted diet:

• improves FVC

• improves DLCO

• reverses HRCT fibrosis

• prevents progression

• improves survival in IPF

Therefore, a distinction is necessary between:

diet modifies the microbiome

and

diet treats pulmonary fibrosis by modifying the microbiome.

The first is supported.

The second remains unproven.

Why Might Diet Matter in Pulmonary Fibrosis?

Diet could influence pulmonary biology indirectly through:

• SCFAs

• tryptophan metabolites

• bile acids

• metabolic health

• systemic inflammation

• intestinal-barrier integrity

Recent pulmonary fibrosis reviews identify all of these as potential gut–lung pathways. (PubMed⁠)

Dietary Fiber

Fiber is one of the best-studied microbiome substrates.

Different fibers can be fermented by intestinal microorganisms.

This generates:

• acetate

• propionate

• butyrate

A 2025 review specifically examined dietary fiber, microbial metabolites and lung immunity, concluding that SCFAs can influence pulmonary immune responses through GPCR signaling, HDAC inhibition and immune-cell programming. (PubMed⁠)

Why Butyrate Is Interesting

Butyrate can:

• support colonocyte metabolism

• strengthen intestinal barrier function

• influence Treg activity

• inhibit histone deacetylases

• modify inflammatory signaling

These effects make butyrate particularly interesting for diseases involving immune and fibrotic pathways.

But increasing dietary fiber does not guarantee clinically meaningful pulmonary butyrate exposure.

Nor has a high-butyrate diet been shown to treat IPF.

Resistant Starch

Resistant starch reaches the colon without being fully digested in the small intestine.

Gut organisms can ferment it and generate SCFAs.

Sources may include selected:

• legumes

• grains

• potatoes

• rice

• green bananas

depending on preparation and individual tolerance.

But patients with substantial bloating, SIBO or dysmotility may not tolerate high amounts.

Mediterranean-Style Diet

A Mediterranean-style pattern commonly includes:

• vegetables

• fruits

• legumes

• nuts

• seeds

• olive oil

• fish

• minimally processed foods

The 2026 systematic review found Mediterranean dietary interventions associated with microbiome and biomarker changes, including enrichment of some metabolically favorable organisms. (PubMed⁠)

This makes the Mediterranean pattern a reasonable general model for metabolic and microbiome health when tolerated.

But it has not been validated as an antifibrotic IPF diet.

Polyphenols

Polyphenols are found in foods such as:

• berries

• herbs

• vegetables

• cocoa

• tea

• olive products

Gut microbes metabolize many polyphenols into bioactive compounds.

Polyphenols may also influence microbial composition.

This represents another diet–microbiome pathway that may be relevant to systemic inflammation.

Direct pulmonary fibrosis trials remain lacking.

Protein and Pulmonary Fibrosis

A microbiome-focused diet must not ignore protein.

People with ILD can experience:

• weight loss

• sarcopenia

• frailty

• reduced exercise capacity

Maintaining muscle is clinically important.

A diet excessively focused on plants or fiber at the expense of adequate protein may be harmful in a patient already losing lean body mass.

Muscle Is Part of Lung Health

Dyspnea can reduce physical activity.

Reduced activity promotes muscle loss.

Loss of skeletal muscle further reduces exercise capacity.

Therefore, the nutrition strategy for pulmonary fibrosis should prioritize:

lung + muscle + metabolism + gut

rather than the microbiome alone.

Western Dietary Patterns

Western dietary patterns are often characterized by:

• highly processed foods

• refined carbohydrates

• low fiber

• low plant diversity

• high saturated fat

Controlled diet studies suggest Western-style dietary patterns can alter microbial ecology and may reduce some beneficial metabolic functions. (PubMed⁠)

This provides another reason to emphasize whole-food dietary patterns.

High-Fat Diet and Endotoxemia

Certain high-fat dietary patterns can influence:

• bile acid metabolism

• intestinal microbial composition

• intestinal permeability

This may increase systemic exposure to LPS in some contexts.

Whether this contributes meaningfully to human pulmonary fibrosis is unknown.

Tryptophan and Diet

Tryptophan is an essential amino acid found in many protein-containing foods.

It can follow several pathways:

• serotonin

• kynurenine

• microbial indoles

Different tryptophan metabolites can have very different immune effects.

Some microbial indoles activate AhR and support mucosal immune regulation.

Other pathways may participate in profibrotic signaling.

This means simply increasing or eliminating dietary tryptophan would be biologically simplistic.

The relevant biology depends on how tryptophan is metabolized.

Bile Acids

Diet influences bile-acid production and microbial transformation.

Gut organisms convert primary bile acids into secondary bile-acid metabolites.

These interact with receptors such as:

• FXR

• TGR5

which influence metabolic and immune signaling.

Bile-acid pathways are emerging as possible mediators of gut–lung communication in fibrosis. (PubMed⁠)

TMAO

Trimethylamine N-oxide is generated through interactions involving diet, intestinal microbes and hepatic metabolism.

Foods containing precursor compounds can influence TMAO production.

TMAO has received substantial cardiovascular attention and is also being investigated in pulmonary fibrosis biology.

Its exact clinical role remains uncertain. (PubMed⁠)

Should Patients With IPF Eat More Fiber?

Not automatically.

For many patients, increasing dietary diversity and fiber gradually may support metabolic and gut health.

But a blanket recommendation can be problematic.

Some ILD patients have:

• severe bloating

• SIBO

• constipation

• diarrhea

• dysmotility

• systemic sclerosis

• reflux

For these individuals, fiber needs to be individualized.

Systemic Sclerosis Is a Special Case

Systemic sclerosis may involve:

• esophageal dysmotility

• gastroparesis

• slow intestinal transit

• SIBO

Simply prescribing a high-fermentation diet may worsen symptoms.

Correcting motility, nutritional deficits and gastrointestinal complications may be more important than maximizing fiber intake.

Low-FODMAP Diet

A low-FODMAP diet can reduce fermentation-related symptoms in selected gastrointestinal conditions.

But the 2026 controlled-trial review found that low-FODMAP patterns can also reduce some SCFA-producing microbial populations. (PubMed⁠)

Therefore, long-term unnecessary restriction may not be ideal.

It should be used strategically when clinically indicated.

Gluten-Free Diet

There is no evidence that all patients with pulmonary fibrosis need to avoid gluten.

A gluten-free diet is clearly indicated in celiac disease.

Outside appropriate indications, unnecessarily restrictive diets may reduce dietary diversity and alter microbiome composition.

Ketogenic Diet

Ketogenic diets significantly alter metabolism and the gut microbiome.

However, there is no evidence that a ketogenic diet treats IPF.

The 2026 systematic review also found ketogenic dietary interventions associated with reductions in some SCFA-producing organisms. (PubMed⁠)

That does not mean ketogenic diets are inherently harmful, but it argues against presenting them as an evidence-based pulmonary fibrosis microbiome strategy.

Intermittent Fasting

Animal work has explored fasting in bleomycin-induced fibrosis.

Some studies suggest altered immune-cell responses and reduced experimental fibrosis. (PubMed⁠)

But this remains preclinical.

Fasting may be inappropriate for patients with:

• low body weight

• sarcopenia

• advanced disease

• inadequate caloric intake

Anti-Inflammatory Diets

“Anti-inflammatory diet” is not one precisely defined medical diet.

In practical terms, it often means a whole-food pattern emphasizing:

• vegetables

• fruits

• quality protein

• healthy fats

• minimally processed foods

This may support general metabolic health.

There is no evidence that such a diet reverses established fibrosis.

Can Diet Change the Lung Microbiome?

Potentially indirectly.

Diet strongly influences the gut microbiome.

Gut-derived immune signals may then affect pulmonary immunity.

Whether dietary modification produces clinically meaningful changes in the lung microbiome of IPF patients remains largely unexplored.

Food Diversity and Microbial Diversity

Greater plant variety provides a broader range of microbial substrates.

This may help support microbial functional diversity.

But there is no magic number of plant foods that has been proven to improve IPF.

Nutrition During Nintedanib

Nintedanib commonly causes gastrointestinal side effects, particularly diarrhea.

Dietary priorities may therefore include:

• maintaining hydration

• maintaining adequate intake

• adjusting foods according to tolerance

A high-fiber microbiome strategy may not be appropriate during significant diarrhea.

Nutrition During Pirfenidone

Pirfenidone can cause:

• nausea

• reduced appetite

• gastrointestinal discomfort

Maintaining adequate calories and protein may take priority over aggressive dietary experimentation.

Functional and Integrative Medicine Perspective

Diet is one of the most reasonable ways to influence the gut microbiome because it:

• acts continuously

• affects microbial substrates

• affects metabolism

• contributes essential nutrients

But an integrative approach should avoid turning food into an unproven antifibrotic prescription.

The clinically appropriate goals include:

• adequate nutrition

• muscle preservation

• metabolic health

• bowel function

• individualized microbial support

What We Know

We know that:

• diet modifies the human gut microbiome

• controlled dietary interventions can alter microbial taxa and metabolites

• fiber influences SCFA production

• SCFAs influence pulmonary immune pathways

• pulmonary fibrosis is associated with altered gut microbiota

(PubMed⁠)

What We Do Not Know

We do not know:

• the ideal IPF microbiome diet

• whether increasing SCFAs changes IPF progression

• whether Mediterranean diets improve fibrosis

• whether microbiome-guided diets improve survival

• which patients might benefit most

What Should a Future Dietary Trial Measure?

Future trials should evaluate:

• diet

• stool metagenomics

• metabolomics

• SCFAs

• inflammatory biomarkers

• FVC

• DLCO

• HRCT progression

• muscle mass

• quality of life

The outcome should be pulmonary benefit—not simply microbiome change.

Frequently Asked Questions

What is the best diet for the gut microbiome in pulmonary fibrosis?

No specific diet has been validated. A diverse, nutrient-dense, minimally processed diet is a reasonable starting framework when tolerated.

Should people with IPF eat more fiber?

Often fiber can support microbial metabolism, but intake should be individualized.

Can a Mediterranean diet reverse fibrosis?

No evidence shows that it reverses lung fibrosis.

Should patients avoid gluten?

Not routinely unless there is a specific indication.

Does diet replace antifibrotic treatment?

No.

Conclusion

Diet unquestionably influences the gut microbiome.

That makes nutrition one of the most interesting potential ways to modify the gut–lung axis.

Current human evidence shows that Mediterranean, plant-rich, high-fiber and high-polyphenol dietary patterns can modify microbial composition and metabolic function. (PubMed⁠)

SCFAs generated by microbial fermentation can influence pulmonary immune responses. (PubMed⁠)

Meanwhile, human IPF research demonstrates that gut microbial features are associated with pulmonary disease severity. (PubMed⁠)

These observations create a coherent biological hypothesis:

diet → microbiome → microbial metabolites → immune regulation → lung

But the final step remains unproven clinically.

There is currently no diet proven to stop or reverse pulmonary fibrosis by changing the microbiome.

For now, the most defensible strategy is to use diet to support:

• nutritional adequacy

• muscle mass

• metabolic health

• gastrointestinal function

• microbial diversity when tolerated

while continuing evidence-based pulmonary treatment.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

Living with Pulmonary Fibrosis or Interstitial Lung Disease?

If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

Can Probiotics Support Lung Health Through the Gut–Lung Axis?

What Does the Gut Have to Do With the Lungs?

The intestine and lungs may appear to be completely separate organs.

But immunologically and metabolically, they communicate continuously.

This communication network is known as the gut–lung axis.

The gut microbiome can influence pulmonary immunity through microbial metabolites and immune signals. Recent reviews describe gut microbiota as important regulators of pulmonary immune responses through metabolites such as short-chain fatty acids, tryptophan derivatives and other microbial products. (PubMed⁠)

Because probiotics can modify aspects of intestinal microbial ecology, researchers have begun asking whether they might support lung health indirectly.

The answer depends heavily on what we mean by “support.”

There is convincing evidence that intestinal microbes influence immunity.

There is growing evidence that probiotics can modify immune responses in selected respiratory diseases.

But there is much less evidence that probiotic supplements can treat established chronic structural lung diseases such as pulmonary fibrosis.

How Does the Gut Communicate With the Lungs?

The major pathways include:

• microbial metabolites

• circulating immune cells

• cytokines

• intestinal-barrier signaling

• bone marrow immune programming

The gut–lung axis is therefore primarily an immune-metabolic network.

SCFAs: One of the Most Important Connections

Dietary fiber is fermented by intestinal microorganisms to generate:

• acetate

• propionate

• butyrate

These SCFAs can enter systemic circulation.

They influence immune cells through G-protein-coupled receptors and epigenetic effects such as HDAC inhibition.

A 2025 review found that dietary fiber and SCFAs can modify pulmonary immune responses and influence immune-cell recruitment to the lung. (PubMed⁠)

Probiotic organisms may potentially contribute indirectly by supporting microbial networks capable of SCFA production.

The Bone Marrow Connection

The gut can influence the lung even before immune cells reach the respiratory tract.

Microbial metabolites can modify hematopoietic cells in bone marrow.

Those cells can subsequently migrate to the lungs.

This helps explain why a dietary or intestinal signal can influence respiratory immunity without bacteria physically moving from gut to lung. (PubMed⁠)

Probiotics and Intestinal Barrier Function

Certain probiotics may support:

• mucus production

• epithelial integrity

• tight junctions

A stronger intestinal barrier may reduce inappropriate systemic exposure to microbial products.

This could theoretically reduce systemic inflammatory signaling.

Probiotics and LPS

Lipopolysaccharide can activate:

TLR4 → NF-κB

and stimulate inflammatory cytokine pathways.

If probiotics improve intestinal microbial ecology and barrier integrity, systemic LPS exposure might potentially decrease.

This remains a mechanistic hypothesis in many chronic lung diseases.

Treg and Th17 Regulation

Gut microbes affect regulatory T cells and Th17 cells.

A balanced immune response requires both effective defense and adequate immune tolerance.

Excessive Th17 signaling has been implicated in several respiratory inflammatory disorders.

Microbiome-dependent modulation of the Treg–Th17 axis is therefore an important area of gut–lung research.

Macrophages

Macrophages are central to respiratory immunity.

Microbial metabolites may influence whether macrophages adopt more inflammatory, repair-oriented or tissue-remodeling phenotypes.

In pulmonary fibrosis, inappropriate macrophage signaling can contribute to fibroblast activation.

Probiotics and Respiratory Infection

The strongest probiotic evidence in respiratory medicine historically relates more to:

• respiratory infections

• immune modulation

• selected airway inflammatory disorders

than to structural fibrotic lung diseases.

This reinforces an important point:

“lung health” encompasses many biological processes and many different diseases.

An intervention that reduces respiratory infection frequency does not automatically treat pulmonary fibrosis.

Asthma and the Gut–Lung Axis

Early-life microbiome composition has been repeatedly associated with immune development and asthma risk.

This has contributed strongly to the overall gut–lung hypothesis.

But asthma is immunologically very different from IPF.

Evidence from asthma should not be automatically extrapolated to fibrosis.

COPD and the Gut Microbiome

Gut dysbiosis has also been described in COPD.

Potential contributors include:

• smoking

• systemic inflammation

• medications

• reduced activity

• diet

Probiotic strategies remain experimental.

Acute Lung Injury and ARDS

Animal models have shown substantial bidirectional communication between the intestine and lungs during critical illness.

Severe lung injury can disrupt intestinal microbial communities and barrier integrity.

This demonstrates that the gut–lung axis is genuinely bidirectional.

Probiotics in Pulmonary Fibrosis

Pulmonary fibrosis provides perhaps one of the most mechanistically intriguing areas.

A 2025 Lactiplantibacillus study found reduced experimental fibrosis accompanied by microbiome remodeling, increased PEA and suppression of TGF-β1/Smad2/3 signaling. (PubMed⁠)

This provides proof of concept in animals.

It is not proof of efficacy in humans.

Diet, Probiotics and Cross-Feeding

Probiotic effects depend partly on diet.

Microorganisms require substrates.

For example, one organism may produce lactate that another bacterium converts into butyrate.

This interaction is known as cross-feeding.

Therefore, taking probiotics while consuming a diet that does not support microbial fermentation may produce very different results from combining probiotics with appropriate dietary substrates.

Why Fiber Matters

Dietary fiber can increase substrates available for SCFA-producing bacteria.

A 2026 systematic review of 80 controlled dietary trials found that dietary interventions can alter gut microbial taxa and metabolic markers. Mediterranean, high-fiber, plant-rich and high-polyphenol dietary patterns were frequently associated with increased SCFA- or lactic-acid-producing organisms or reduced opportunistic organisms. (PubMed⁠)

This suggests that diet may sometimes be a more powerful microbiome intervention than probiotic supplementation alone.

Not Everyone Needs More Fermentation

A universal recommendation for more fiber or probiotics is inappropriate.

Some people have:

• SIBO

• significant bloating

• intestinal dysmotility

• systemic sclerosis

• altered bowel habits

In these individuals, large amounts of fermentable substrates may initially worsen symptoms.

Probiotics and the Oral–Gut–Lung Network

Respiratory microbial ecology is influenced not only by the gut.

The oral cavity is a major source of microorganisms entering the lower respiratory tract through microaspiration.

Future respiratory microbiome research may increasingly consider:

oral microbiome + lung microbiome + gut microbiome

as an interconnected system.

Can Probiotics Prevent Lung Disease?

There is insufficient evidence to recommend probiotics broadly for prevention of chronic lung disease.

The effectiveness likely depends on:

• age

• disease

• microbial baseline

• probiotic strain

• diet

• medications

• environmental exposures

Can Probiotics Improve Pulmonary Function?

No general probiotic has been proven to meaningfully improve pulmonary function across chronic respiratory diseases.

Studies must be interpreted disease by disease.

Can Probiotics Reduce Lung Inflammation?

Selected probiotics can modify systemic and respiratory inflammatory signals in experimental and some clinical settings.

However, “reducing inflammation” is not the same as improving long-term disease outcomes.

This distinction is especially important in pulmonary fibrosis.

Can Probiotics Improve Lung Fibrosis?

There is currently no adequate human evidence showing that probiotics reverse established lung fibrosis.

The data remain predominantly preclinical. (PubMed⁠)

Probiotics and Immunosuppressed Patients

People with autoimmune ILD may receive substantial immunosuppression.

In this population, probiotic decisions should be individualized.

Rare invasive infections associated with probiotic organisms have occurred in severely vulnerable patients.

What About Fermented Foods?

Fermented foods can contain living microorganisms and microbial metabolites.

But they are not equivalent to standardized probiotic supplements.

Their microbial composition varies substantially.

They may fit within a healthy diet for many individuals but should not be presented as pulmonary treatment.

Functional and Integrative Medicine Perspective

The gut–lung axis provides a scientifically plausible framework for incorporating gastrointestinal and nutritional health into respiratory care.

An integrative approach may assess:

• dietary diversity

• gastrointestinal symptoms

• bowel function

• reflux

• nutritional status

• metabolic health

Probiotics may be considered selectively.

But treatment should remain disease-specific.

What We Know

We know that:

• gut microbial metabolites influence pulmonary immunity

• diet modifies intestinal microbial ecology

• SCFAs influence immune responses in the lungs

• probiotics can modify gut ecology and immune signaling

• selected probiotic interventions have shown pulmonary benefits experimentally

(PubMed⁠)

What We Do Not Know

We do not know:

• the optimal probiotic for general lung health

• which strains work for which respiratory disease

• the optimal duration

• whether baseline microbiome testing can identify responders

• whether routine supplementation improves long-term respiratory outcomes

Frequently Asked Questions

Are probiotics good for the lungs?

They may influence lung immunity through the gut–lung axis, but benefits depend on the specific probiotic, disease and clinical context.

Which probiotic is best for lung health?

No single probiotic has been established as the best probiotic for respiratory health.

Can gut bacteria affect the lungs?

Yes. Microbial metabolites and immune signals from the intestine can influence pulmonary immunity.

Can probiotics increase SCFAs?

Certain probiotic ecosystems may support SCFA production, especially when appropriate dietary substrates are available.

Are probiotics a replacement for respiratory medication?

No.

Conclusion

The scientific basis of the gut–lung axis is increasingly strong.

Gut microorganisms produce metabolites capable of influencing:

• pulmonary immune cells

• epithelial responses

• bone marrow immune programming

• systemic inflammation

Probiotics may potentially alter some of these pathways.

But the phrase “probiotics support lung health” should not be interpreted as evidence that a probiotic supplement treats all lung diseases.

Different diseases have fundamentally different biology.

For pulmonary fibrosis in particular, probiotic research is promising but remains experimental.

The future may lie in precision approaches that identify the right:

microorganism + dietary substrate + microbial metabolite + patient phenotype.

That would represent a much more sophisticated strategy than simply recommending a generic probiotic for everyone with lung disease.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

Living with Pulmonary Fibrosis or Interstitial Lung Disease?

If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

Probiotics in Pulmonary Fibrosis: What Does the Evidence Actually Show?

Can Probiotics Help Pulmonary Fibrosis?

Interest in probiotics has expanded far beyond digestive health.

Researchers are now investigating whether microorganisms living in the intestine can influence organs located far from the gastrointestinal tract—including the lungs.

This communication network is known as the gut–lung axis.

Pulmonary fibrosis has recently become an important area of gut–lung research.

Studies have identified changes in the intestinal microbiome in pulmonary fibrosis, while experimental research suggests that microbial metabolites can influence:

• immune regulation

• intestinal barrier integrity

• epithelial injury

• fibroblast activation

• autophagy

• fibrotic signaling

This naturally raises an important question:

Could probiotics modify the gut microbiome in a way that helps pulmonary fibrosis?

The answer is scientifically interesting but clinically cautious.

Experimental studies suggest that selected probiotic organisms can reduce lung inflammation and fibrosis in animal models.

A particularly interesting 2025 study found that a strain of Lactiplantibacillus reduced bleomycin-induced pulmonary fibrosis in mice, modified the gut microbiome and increased a circulating metabolite linked with suppression of TGF-β-related fibrotic signaling. (PubMed⁠)

However:

There is currently no probiotic proven in human clinical trials to stop, reverse or reliably slow idiopathic pulmonary fibrosis.

That distinction should guide both conventional and integrative approaches.

What Are Probiotics?

Probiotics are live microorganisms that, when administered in adequate amounts, may provide a health benefit.

Common probiotic groups include species belonging to:

• Lactobacillus

• Lacticaseibacillus

• Lactiplantibacillus

• Bifidobacterium

• Saccharomyces

But the word “probiotic” can be misleading if used too broadly.

Probiotic effects are generally:

strain-specific.

A benefit demonstrated with one strain cannot automatically be attributed to another organism from the same genus.

For example, a study showing an effect from one Lactiplantibacillus strain does not prove that every Lactobacillus-containing supplement will produce the same result.

This is particularly important when discussing pulmonary fibrosis, because commercially available probiotic supplements are extremely heterogeneous.

Why Study Probiotics in a Lung Disease?

The rationale comes from the gut–lung axis.

The gut microbiome produces biologically active substances capable of entering systemic circulation.

These include:

• short-chain fatty acids

• tryptophan-derived metabolites

• bile-acid metabolites

• lipid metabolites

• microbial peptides

Gut microorganisms also influence:

• intestinal-barrier integrity

• regulatory T cells

• Th17 cells

• macrophages

• dendritic cells

• inflammatory cytokines

These immune and metabolic signals may influence lung physiology.

A major 2025 review of pulmonary fibrosis identified immune dysregulation, barrier dysfunction, epithelial–mesenchymal signaling, autophagy and microbial peptide-mediated epithelial injury as major potential mechanisms linking microbiota with fibrosis. (PubMed⁠)

A 2026 review further emphasized SCFAs, bile acids, tryptophan metabolites, LPS and TMAO as potential mediators linking the intestinal microbiome with pulmonary fibrosis. (PubMed⁠)

Therefore, researchers are not proposing that probiotics physically travel from the intestine into the lungs.

Instead, probiotics may theoretically alter the microbial ecosystem and its metabolites, which could then influence pulmonary immunity.

Is the Gut Microbiome Actually Altered in Human IPF?

Yes.

One of the strongest human studies was published in 2026.

Investigators analyzed fecal microbiota from 411 patients with idiopathic pulmonary fibrosis enrolled in the CleanUP-IPF trial.

They used 16S sequencing and shotgun metagenomic methods.

Gut microbial composition varied with factors including:

• age

• sex

• proton-pump inhibitor use

More importantly, gut microbiota characteristics were associated with percent predicted DLCO, and selected microbial features were associated with transplant-free survival in certain analyses. (PubMed⁠)

This provides important evidence that intestinal microbial ecology is associated with clinically meaningful features of human IPF.

But it does not demonstrate that giving probiotics improves IPF.

What Happens to the Gut Microbiome in Experimental Pulmonary Fibrosis?

Animal models provide stronger mechanistic evidence.

Bleomycin-induced pulmonary fibrosis can produce substantial alterations in intestinal microbial composition.

A study comparing animals housed under different microbial conditions found that germ-free mice were relatively protected against pulmonary fibrosis.

Mice with different intestinal microbiomes developed different degrees of fibrosis.

Most strikingly, transferring stool from mice with the microbiome associated with more severe fibrosis into germ-free mice transferred a more severe fibrotic phenotype.

The more severe phenotype was associated with increased:

IL-6 → STAT3 → IL-17A signaling. (PubMed⁠)

This experiment provides unusually strong evidence that gut microbiota can modify fibrosis severity—at least in mice.

That is considerably stronger than merely observing dysbiosis.

But mouse fibrosis remains biologically different from human IPF.

The 2025 Lactiplantibacillus LP03 Study

One of the most interesting recent probiotic studies evaluated three strains in a bleomycin pulmonary fibrosis model.

Among them, Lactiplantibacillus sp. LP03 showed the strongest antifibrotic effect.

Researchers reported reductions in:

• mortality

• systemic inflammation

• interstitial thickening

• collagen deposition

• epithelial-to-mesenchymal transition

LP03 also altered intestinal microbial composition.

There was increased abundance of organisms including:

• Ligilactobacillus

• Akkermansia

But perhaps the most interesting finding came from metabolomics.

LP03 increased circulating palmitoylethanolamide, or PEA.

When PEA was administered independently, it also reduced experimental fibrosis.

Mechanistic studies suggested inhibition of:

TGF-β1 → Smad2/3 signaling

and suppression of epithelial-to-mesenchymal transition. (PubMed⁠)

This study illustrates an important emerging concept.

A probiotic may not act simply because it is a “good bacterium.”

It may work by altering the microbial ecosystem and producing downstream metabolic signals.

Does This Mean LP03 Is a Treatment for IPF?

No.

The experiment was performed in a bleomycin mouse model.

It did not demonstrate that LP03:

• improves human FVC

• improves DLCO

• slows HRCT progression

• reduces acute exacerbations

• improves survival

• replaces antifibrotic therapy

The finding identifies a candidate pathway for future research.

It does not establish clinical efficacy.

Probiotics May Work Through Microbial Metabolites

The LP03 study supports a wider principle:

the therapeutic effect may come from what microorganisms produce rather than merely which microorganisms are present.

Potential microbiome-derived mediators include:

• SCFAs

• PEA

• indole metabolites

• bile-acid derivatives

This may ultimately shift the field from conventional probiotics toward postbiotics.

Postbiotics include microbial products or metabolites that may provide biological effects without requiring administration of living organisms.

For pulmonary fibrosis, this may eventually be more predictable than simply administering broad probiotic combinations.

Short-Chain Fatty Acids and Probiotic Effects

Probiotic organisms can potentially alter networks of bacteria involved in production of:

• acetate

• propionate

• butyrate

These short-chain fatty acids influence immune and epithelial biology.

They may act through receptors including:

• GPR41

• GPR43

• GPR109A

and through inhibition of histone deacetylases.

SCFAs can influence:

• regulatory T cells

• macrophages

• intestinal barrier integrity

• cytokine production

A 2025 review highlighted dietary fiber and SCFA production as major components of microbiota-mediated lung immune regulation. (PubMed⁠)

However, increasing probiotic bacteria does not guarantee increased SCFA availability.

SCFA production depends on:

• microbial species

• microbial cross-feeding

• dietary substrates

• intestinal environment

This is why diet and probiotics cannot be considered separately.

Probiotics and the Intestinal Barrier

Another proposed mechanism is improved intestinal-barrier integrity.

Certain probiotics can support:

• tight-junction proteins

• mucus production

• epithelial function

If intestinal permeability decreases, systemic exposure to microbial products such as LPS might also decrease.

A theoretical pathway could therefore be:

Probiotic
↓
improved microbial ecosystem
↓
improved intestinal barrier
↓
reduced microbial translocation
↓
less systemic inflammatory signaling
↓
potential pulmonary benefit

This is biologically plausible.

It remains unproven as a therapeutic pathway in human pulmonary fibrosis.

Probiotics and Treg–Th17 Balance

Gut microorganisms influence differentiation of regulatory T cells and Th17 cells.

Th17 signaling is particularly interesting in pulmonary fibrosis.

Experimental microbiome work has linked more severe fibrosis with greater IL-6/STAT3/IL-17A signaling. (PubMed⁠)

A probiotic that restores microbial balance could theoretically:

• increase regulatory signals

• decrease excessive Th17 activation

• modify macrophage polarization

However, this has not yet translated into an established probiotic therapy for IPF.

Can Probiotics Influence Fibroblasts?

Potentially—but indirectly.

Fibroblasts are unlikely to be affected because probiotic bacteria reach lung tissue.

Instead, microbial metabolites may influence pathways such as:

• TGF-β

• Smad2/3

• PI3K/AKT

• mTOR

• NF-κB

• oxidative stress pathways

The LP03 study is a good example because the probiotic was associated with increased PEA, which then influenced TGF-β/Smad signaling. (PubMed⁠)

This reinforces the importance of metabolomics in future probiotic trials.

What About Akkermansia?

Akkermansia muciniphila has received substantial interest in microbiome research because of associations with:

• metabolic health

• mucus layer function

• intestinal-barrier biology

LP03 increased Akkermansia in the experimental pulmonary fibrosis study.

However, this does not mean that commercially taking Akkermansia will treat pulmonary fibrosis.

No human trial has established this.

What About Bifidobacterium?

Some experimental pulmonary fibrosis research has implicated Bifidobacterium and other organisms as potentially protective microbial components.

In the murine microbiome-transfer experiment, the microbiome associated with less fibrosis had greater abundance of Bifidobacterium and Lactobacilli. (PubMed⁠)

Again, this demonstrates an ecological association.

It does not identify a validated human IPF probiotic prescription.

Probiotics Are Not Interchangeable

One of the biggest mistakes in translating microbiome science into functional medicine is assuming:

beneficial genus = beneficial supplement.

Microbial effects may differ at the:

• species level

• strain level

and sometimes according to the host.

Therefore:

Lactobacillus rhamnosus is not identical to Lactiplantibacillus plantarum.

One Bifidobacterium longum strain is not necessarily identical to another.

The appropriate scientific unit in probiotic research is often the specific strain, not just the genus.

Is There Human Evidence That Probiotics Treat IPF?

At present, adequate randomized controlled human evidence demonstrating disease-modifying efficacy is lacking.

There is no established probiotic shown to produce clinically meaningful improvement in:

• FVC decline

• DLCO

• HRCT fibrosis

• hospitalization

• transplant-free survival

• overall survival

For this reason, probiotics should not currently be described as an antifibrotic treatment.

Can Probiotics Be Used Alongside Antifibrotic Therapy?

Patients may use probiotics for separate gastrointestinal reasons.

However, a person taking:

• nintedanib

• pirfenidone

• immunomodulators

should not assume a probiotic is automatically appropriate.

The clinical context matters.

For example, nintedanib commonly causes diarrhea.

Patients with systemic sclerosis may have:

• dysmotility

• SIBO

• severe bloating

Some individuals may tolerate probiotics poorly.

A personalized approach is preferable.

Probiotics in Autoimmune-Associated ILD

The microbiome may be especially relevant in autoimmune ILD.

Dysbiosis has been reported in:

• systemic sclerosis

• rheumatoid arthritis

• inflammatory myopathies

But there is still no probiotic proven to modify ILD progression in these diseases.

GI symptom improvement and pulmonary disease modification should be considered separate outcomes.

Are Probiotics Safe?

For most immunocompetent adults, conventional probiotics are generally well tolerated.

But caution may be appropriate in:

• severe immunosuppression

• critical illness

• central venous catheter use

• major intestinal barrier disruption

Rare cases of probiotic-associated bloodstream infection have been described in vulnerable populations.

Therefore, “natural” does not mean completely risk-free.

What About Multi-Strain Probiotic Products?

More strains do not necessarily mean greater benefit.

A 20-strain formulation is not automatically superior to a precisely studied single strain.

In pulmonary fibrosis, there is currently no validated multi-strain formulation.

The future may instead involve targeted consortia chosen according to:

• microbial function

• metabolic output

• patient phenotype

Probiotics Versus Prebiotics

Probiotics provide microorganisms.

Prebiotics provide substrates that selectively support microbial activity.

Examples include certain fermentable fibers.

The combination is sometimes called a synbiotic.

For gut–lung biology, supporting existing beneficial organisms through diet may eventually be as important as adding new organisms.

Probiotics Versus Postbiotics

Postbiotics may include:

• microbial metabolites

• microbial components

• inactivated microorganisms

For pulmonary fibrosis, postbiotics are especially interesting because researchers may eventually identify the precise metabolite responsible for a protective effect.

The LP03–PEA finding illustrates this possibility. (PubMed⁠)

Rather than asking:

Which probiotic should we give?

future research may ask:

Which microbial molecule should we target?

Functional and Integrative Medicine Perspective

Functional and integrative medicine can contribute constructively to this field when evidence boundaries remain clear.

A comprehensive approach may assess:

• diet

• bowel symptoms

• reflux

• medication effects

• nutritional status

• SIBO when clinically suspected

• metabolic health

Probiotics may sometimes form part of gastrointestinal care.

But they should not be sold as a way to reverse lung scarring.

The goal should be:

supporting overall gastrointestinal and metabolic health while continuing evidence-based pulmonary care.

What We Know

We know that:

• the gut microbiome can influence pulmonary immunity

• intestinal dysbiosis occurs in pulmonary fibrosis models

• gut microbial composition is associated with severity in human IPF

• microbiome transfer can alter fibrosis severity in mice

• selected probiotics can reduce experimental pulmonary fibrosis

• microbial metabolites may mediate these effects

• LP03 produced significant antifibrotic effects in a 2025 mouse study

(PubMed⁠)

What We Do Not Know

We do not know:

• whether probiotics prevent human IPF progression

• which strain would be optimal

• which patients might respond

• what dose would be required

• how long treatment should continue

• whether probiotics interact meaningfully with antifibrotics

• whether microbiome changes translate into better survival

What Would a Good Human Trial Look Like?

A rigorous trial should use a clearly identified probiotic strain or microbial consortium.

It should evaluate:

• baseline microbiome

• metabolomics

• FVC

• DLCO

• HRCT

• symptoms

• adverse effects

• disease progression

• treatment interaction

Most importantly, changing stool bacteria would not be enough.

A genuine pulmonary treatment would need to improve meaningful lung outcomes.

Frequently Asked Questions

What is the best probiotic for pulmonary fibrosis?

No probiotic has been established as the best probiotic for IPF or pulmonary fibrosis.

Can probiotics reverse lung fibrosis?

There is no human clinical evidence that probiotics reverse established lung fibrosis.

Do probiotics reduce inflammation in the lungs?

Selected probiotics can modify immune responses and have reduced pulmonary inflammation in experimental studies, but results cannot automatically be generalized to human IPF.

Can probiotics increase butyrate?

Certain microbial ecosystems can support SCFA production, but probiotic supplementation does not reliably guarantee increased butyrate.

Should everyone with IPF take probiotics?

No. Probiotic use should depend on the individual gastrointestinal and clinical context.

Conclusion

The relationship between probiotics and pulmonary fibrosis is one of the most interesting emerging areas within gut–lung research.

Experimental evidence increasingly demonstrates that manipulation of intestinal microbiota can alter the severity of lung fibrosis.

The 2025 LP03 study is particularly important because it linked probiotic treatment with:

• changes in the gut microbiome

• increased systemic PEA

• reduced TGF-β/Smad signaling

• reduced collagen deposition and experimental fibrosis

(PubMed⁠)

Other experiments demonstrate that transferring different intestinal microbial ecosystems between mice can alter fibrosis severity, providing evidence that the microbiome itself can influence the phenotype. (PubMed⁠)

At the same time, human research now shows that intestinal microbial composition is associated with IPF severity and transplant-free survival. (PubMed⁠)

Together, these findings provide strong biological justification for studying probiotics.

But they do not establish probiotics as a treatment for human pulmonary fibrosis.

No probiotic has yet been proven to slow FVC decline, reverse fibrosis or improve survival in IPF.

The most promising future direction may therefore be more precise than conventional probiotic supplementation.

Researchers may ultimately identify:

• specific strains

• microbial consortia

• postbiotics

• microbial metabolites

that target defined pathways in selected patients.

Until then, probiotics should be viewed as a promising research strategy, not an established antifibrotic therapy.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

Living with Pulmonary Fibrosis or Interstitial Lung Disease?

If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

Vitamin D and Pulmonary Fibrosis: Does Vitamin D Deficiency Affect IPF?

Vitamin D is usually associated with bone health and calcium metabolism.

But vitamin D is also involved in:

• immune regulation

• inflammatory signaling

• epithelial function

• cellular differentiation

• fibroblast biology

These functions have led researchers to investigate whether vitamin D could play a role in chronic lung diseases—including interstitial lung disease and pulmonary fibrosis.

The question has become particularly interesting because several studies have reported that patients with idiopathic pulmonary fibrosis, or IPF, who have low vitamin D levels may have:

• worse lung function

• greater disease severity

• poorer survival

At the same time, experimental studies suggest that vitamin D can directly interfere with biological pathways involved in lung fibrosis.

Most recently, a 2026 experimental study found that vitamin D reduced pulmonary fibrosis by suppressing abnormal fibroblast metabolism through a newly described:

TK1 → PFKFB3 → glycolysis pathway. (PubMed)

This adds an interesting new mechanism to earlier research involving vitamin D receptor signaling and TGF-β-related fibrosis.

But an important distinction must be made:

Evidence that vitamin D deficiency is associated with pulmonary fibrosis does not prove that vitamin D supplementation treats pulmonary fibrosis.

At present, vitamin D should be considered an important nutritional and metabolic factor to assess and correct when deficient—not an established antifibrotic treatment.

What Is Vitamin D?

Vitamin D is a fat-soluble vitamin that also functions as a steroid-like hormone.

The two major forms are:

• vitamin D2, or ergocalciferol

• vitamin D3, or cholecalciferol

Vitamin D3 can be produced in the skin after ultraviolet-B exposure and can also be obtained from food or supplements.

Vitamin D undergoes several metabolic steps.

First, it is converted mainly in the liver to:

25-hydroxyvitamin D — 25(OH)D

This is the form generally measured in blood tests to assess vitamin D status.

It is subsequently converted to the biologically active hormone:

1,25-dihydroxyvitamin D — calcitriol.

The effects of calcitriol are mediated largely through the vitamin D receptor, or VDR, which is expressed in many tissues beyond bone—including immune and pulmonary cells. (PubMed)

Vitamin D Is More Than a Bone Vitamin

Vitamin D influences several biological processes relevant to pulmonary fibrosis.

These include:

• innate immunity

• adaptive immunity

• inflammatory cytokines

• oxidative stress

• epithelial-cell biology

• fibroblast activation

• extracellular matrix production

This provides the biological rationale for studying vitamin D in fibrotic lung disease.

What Happens in Pulmonary Fibrosis?

Pulmonary fibrosis involves abnormal repair after lung epithelial injury.

A simplified sequence is:

alveolar epithelial injury
↓
abnormal repair signaling
↓
fibroblast activation
↓
myofibroblast formation
↓
collagen and extracellular matrix deposition
↓
progressive lung fibrosis

One of the central signaling molecules involved is:

TGF-β1

or transforming growth factor beta-1.

Vitamin D has been investigated because experimental evidence suggests it may interfere with several components of this fibrotic cascade.

Is Vitamin D Deficiency Common in Pulmonary Disease?

Low vitamin D levels are frequently reported across chronic respiratory diseases.

A major 2026 review published by the European Respiratory Society examined vitamin D across:

• asthma

• COPD

• interstitial lung disease

• lung cancer

• tuberculosis

• respiratory infections

The review concluded that vitamin D insufficiency is repeatedly associated with poorer respiratory outcomes.

However, it also emphasized an important problem:

clinical intervention trials have not consistently reproduced the benefits predicted by observational and mechanistic research. (PubMed)

This discrepancy is crucial when discussing vitamin D and pulmonary fibrosis.

Is Vitamin D Deficiency Associated With IPF?

Several observational studies suggest that it is.

One influential study examined vitamin D in patients with idiopathic pulmonary fibrosis and found that vitamin D deficiency correlated with several markers of disease severity.

Lower vitamin D was associated with poorer:

• FVC

• DLCO

and higher disease severity according to the GAP score.

Most notably, vitamin D deficiency was associated with increased all-cause mortality.

The reported hazard ratio was approximately:

HR 3.7

for mortality among vitamin D-deficient patients. (PubMed)

This is a substantial association.

But it requires careful interpretation.

Does Low Vitamin D Cause Worse IPF?

Not necessarily.

This is one of the central problems with observational nutrition research.

Low vitamin D could contribute biologically to disease.

But severe pulmonary fibrosis could also lead to low vitamin D.

For example, patients with more advanced disease may:

• spend less time outdoors

• receive less sunlight

• exercise less

• have poorer nutritional intake

• have lower body weight or muscle mass

• have more systemic illness

Therefore:

severe disease → lower vitamin D

is also possible.

The relationship may be bidirectional.

Could Vitamin D Simply Be a Marker of Overall Health?

Yes.

Vitamin D status can reflect multiple aspects of health and lifestyle.

Low 25(OH)D may sometimes act as a marker of:

• frailty

• nutritional status

• reduced outdoor activity

• chronic inflammation

• comorbidity

Therefore, even a strong association between vitamin D deficiency and mortality does not prove that correcting vitamin D will reduce mortality.

This is why randomized trials are so important.

What Does Experimental Research Show?

Experimental research is considerably more supportive of a direct biological effect.

Vitamin D has demonstrated antifibrotic effects in:

• cultured lung fibroblasts

• animal pulmonary fibrosis models

Earlier experimental work suggested that vitamin D could interfere with fibroblast activation and extracellular matrix production.

The newest mechanistic research has expanded this considerably.

The Important 2026 Vitamin D–Pulmonary Fibrosis Study

A study published in the Journal of Translational Medicine in April 2026 investigated how vitamin D affects fibroblast metabolism during pulmonary fibrosis.

Researchers studied:

• human MRC-5 lung fibroblasts

• primary mouse lung fibroblasts

• experimental pulmonary fibrosis models

They focused particularly on abnormal glucose metabolism within activated fibroblasts. (PubMed)

Why Is Fibroblast Metabolism Important?

Activated fibroblasts require substantial energy to:

• proliferate

• differentiate

• produce collagen

• synthesize extracellular matrix

Fibrotic fibroblasts undergo metabolic reprogramming.

One important change is increased:

glycolysis

—the cellular pathway used to metabolize glucose.

This metabolic shift helps support the energy requirements of activated myofibroblasts.

Therefore, abnormal fibroblast metabolism itself may become a therapeutic target.

Vitamin D and Glycolysis

The 2026 study identified an important pathway involving:

thymidine kinase 1 — TK1

and

PFKFB3

a major regulator of glycolysis.

Researchers found that TGF-β1 increased TK1.

TK1 promoted PFKFB3-driven glycolysis.

This supported fibroblast activation and pulmonary fibrosis.

Vitamin D inhibited this pathway. (PubMed)

The proposed sequence was:

Vitamin D
↓
TK1 inhibition
↓
PFKFB3 suppression
↓
reduced glycolysis
↓
reduced fibroblast activation
↓
less experimental pulmonary fibrosis

This provides a novel metabolic explanation for vitamin D’s potential antifibrotic effects.

Why Is PFKFB3 Important?

PFKFB3 is an important regulator of cellular glycolysis.

Fibroblasts undergoing activation may depend increasingly on glycolytic metabolism.

Therefore, reducing PFKFB3 activity could potentially reduce the metabolic capacity required for fibroblasts to become collagen-producing myofibroblasts.

This concept fits into a much broader area of modern fibrosis research:

metabolic reprogramming in pulmonary fibrosis.

Vitamin D and TGF-β

TGF-β is one of the major drivers of pulmonary fibrosis.

It promotes:

• fibroblast activation

• myofibroblast differentiation

• collagen production

• extracellular matrix deposition

Earlier experimental research has suggested that vitamin D/VDR signaling can interfere with TGF-β-related fibrotic pathways.

The new metabolic evidence adds another layer to this interaction.

Vitamin D may therefore influence fibrosis through multiple mechanisms rather than a single signaling pathway.

Vitamin D Receptor and Fibroblasts

The biological effects of active vitamin D are largely mediated through the vitamin D receptor.

When activated, VDR can influence transcription of numerous genes.

Experimental fibrosis research suggests that adequate VDR signaling may help oppose some profibrotic transcriptional programs.

This has generated interest in the VDR as a potential therapeutic target.

But VDR-targeted antifibrotic therapy remains experimental.

Vitamin D and Collagen Production

One of the hallmarks of pulmonary fibrosis is excessive collagen deposition.

Experimental vitamin D studies have reported reductions in:

• collagen synthesis

• fibroblast proliferation

• myofibroblast differentiation

These findings support an antifibrotic biological effect.

But again, this evidence is mainly derived from laboratory and animal studies.

Vitamin D and the Immune System

Vitamin D also has substantial immunomodulatory effects.

It can influence:

• macrophages

• dendritic cells

• T lymphocytes

• regulatory T cells

• inflammatory cytokines

These effects may be particularly relevant in inflammatory or autoimmune forms of ILD.

However, IPF is no longer considered primarily an inflammatory disease.

The central pathology involves epithelial injury and abnormal fibrotic repair.

Therefore, vitamin D’s potential relevance to IPF probably extends beyond its anti-inflammatory properties.

Vitamin D and Oxidative Stress

Oxidative stress contributes to epithelial injury and fibroblast activation.

Experimental studies suggest vitamin D may influence antioxidant pathways and cellular responses to oxidative stress.

This provides another potential connection between vitamin D deficiency and fibrotic biology.

Vitamin D and Epithelial Cells

Pulmonary fibrosis is increasingly understood as a disease involving dysfunctional alveolar epithelial repair.

Vitamin D receptors are present in epithelial tissues.

Vitamin D may influence:

• epithelial differentiation

• barrier function

• immune responses

• cellular survival

Whether correcting vitamin D deficiency improves alveolar epithelial repair in human IPF remains unknown.

Vitamin D and Cellular Senescence

Cellular senescence is increasingly recognized as an important mechanism in IPF.

Senescent alveolar epithelial cells can release inflammatory and profibrotic mediators known collectively as the:

senescence-associated secretory phenotype, or SASP.

Vitamin D has been investigated in cellular aging and oxidative stress pathways.

However, direct evidence that vitamin D supplementation modifies pulmonary cellular senescence in patients with IPF is currently insufficient.

Vitamin D and Autophagy

Autophagy allows cells to remove:

• damaged proteins

• dysfunctional organelles

• cellular debris

Impaired autophagy is implicated in pulmonary fibrosis.

Vitamin D signaling may interact with cellular metabolic and autophagy pathways.

This represents another mechanistic area worthy of investigation, but it has not yet produced an established vitamin D-based IPF therapy.

What About Autoimmune Interstitial Lung Disease?

Vitamin D becomes particularly interesting when ILD occurs in autoimmune disease.

Examples include:

• systemic sclerosis

• rheumatoid arthritis

• inflammatory myositis

• antisynthetase syndrome

• Sjögren disease

Vitamin D has immunomodulatory properties, and deficiency is common in several autoimmune conditions.

Systemic sclerosis provides particularly interesting data.

Vitamin D and Systemic Sclerosis

A 2024 systematic review, meta-analysis and meta-regression examined vitamin D in systemic sclerosis.

The analysis found that lower vitamin D levels were associated with:

• susceptibility to systemic sclerosis

• occurrence of interstitial lung disease

• higher systolic pulmonary arterial pressure

• greater skin involvement

Specifically, lower vitamin D was significantly associated with the occurrence of ILD. (PubMed)

This is important observational evidence.

But once again:

association does not demonstrate that vitamin D supplementation prevents or treats SSc-ILD.

Vitamin D and Pulmonary Hypertension in Systemic Sclerosis

The same meta-analysis reported an association between vitamin D deficiency and higher estimated systolic pulmonary artery pressure. (PubMed)

This is interesting because systemic sclerosis can cause pulmonary vascular disease as well as ILD.

However, vitamin D should not be considered a treatment for pulmonary hypertension on the basis of this association.

Why Could Vitamin D Be Low in Systemic Sclerosis?

Potential contributors include:

• reduced sun exposure

• gastrointestinal involvement

• malabsorption

• dietary factors

• chronic inflammation

• medication effects

• reduced physical activity

Therefore, vitamin D deficiency may be both a biological factor and a consequence of chronic systemic disease.

Does Vitamin D Supplementation Treat Pulmonary Fibrosis?

At present:

No clinical evidence demonstrates that vitamin D supplementation is an established treatment for pulmonary fibrosis.

This is the most important clinical message.

The 2026 ERS review emphasizes that although mechanistic and observational evidence is compelling in several respiratory diseases, intervention studies have produced mixed results. (PubMed)

Large, well-designed randomized trials specifically targeting vitamin D-deficient patients with pulmonary fibrosis are still needed.

Does Vitamin D Reverse Lung Fibrosis?

There is no evidence that oral vitamin D supplementation reverses established pulmonary fibrosis in humans.

Experimental reduction of fibrosis in mice should not be interpreted as evidence of reversal in human IPF.

Should Vitamin D Deficiency Still Be Corrected?

Yes—when a patient is genuinely deficient, vitamin D has established health implications independent of pulmonary fibrosis.

Vitamin D is important for:

• bone health

• calcium metabolism

• muscle function

These are particularly relevant in chronic lung disease.

Patients with advanced ILD may already be vulnerable to:

• physical deconditioning

• muscle weakness

• falls

• osteoporosis

Some may also receive corticosteroids, depending on the ILD subtype, which can further increase bone risk.

Correcting deficiency is therefore clinically reasonable even without claiming an antifibrotic effect.

Vitamin D, Muscle and Pulmonary Rehabilitation

This is an often overlooked area.

Pulmonary fibrosis reduces exercise capacity.

Reduced activity contributes to:

deconditioning → muscle loss → poorer exercise tolerance

Vitamin D deficiency may contribute to impaired musculoskeletal health.

Therefore, correcting deficiency may support the broader goals of:

• maintaining muscle

• preserving mobility

• supporting rehabilitation

• protecting bone

These are clinically meaningful outcomes even if vitamin D does not alter fibrosis itself.

What Vitamin D Test Should Be Measured?

The standard clinical test for vitamin D status is:

serum 25-hydroxyvitamin D — 25(OH)D.

Routine measurement of 1,25-dihydroxyvitamin D is generally not the appropriate test for assessing ordinary vitamin D nutritional status.

What Level Is Considered Deficient?

Definitions vary between professional organizations and clinical contexts.

Historically, concentrations below approximately 20 ng/mL have commonly been classified as deficient in many clinical frameworks.

However, debates continue regarding:

• optimal thresholds

• population screening

• ideal targets

For pulmonary fibrosis specifically, no evidence-based “antifibrotic vitamin D level” has been established.

This point is important.

There is no validated target such as:

“Vitamin D must be above X to slow IPF.”

Is More Vitamin D Better?

No.

Vitamin D is fat-soluble.

Excessive supplementation can cause toxicity.

Potential consequences include:

• hypercalcemia

• kidney stones

• kidney injury

• gastrointestinal symptoms

• neurological symptoms

Therefore, supplementation should be based on appropriate clinical assessment rather than the assumption that higher levels produce greater antifibrotic effects.

What About Vitamin D3 With Vitamin K2?

Vitamin D3 and vitamin K2 are frequently combined in supplements.

Vitamin K has important roles in coagulation and bone metabolism.

But there is no clinical evidence showing that combining vitamin D3 with K2 provides an antifibrotic treatment for IPF.

Patients taking anticoagulants, particularly vitamin K antagonists, should also discuss vitamin K supplementation with their treating clinician.

Can Sunlight Replace Supplements?

Sun exposure can contribute to vitamin D production.

But vitamin D synthesis varies according to:

• season

• latitude

• skin pigmentation

• clothing

• age

• time outdoors

Patients with advanced pulmonary disease may also spend less time outdoors.

Therefore, blood testing can be more informative than assuming sun exposure is adequate.

Vitamin D and the Gut Microbiome

Vitamin D and the intestinal microbiome may also interact.

Vitamin D receptor signaling can influence:

• intestinal epithelial function

• mucosal immunity

• microbial ecology

Conversely, the microbiome may influence host immune and metabolic responses.

This raises an interesting possibility that vitamin D could interact with the gut–lung axis.

However, there is currently insufficient evidence to claim that vitamin D improves pulmonary fibrosis through microbiome modification.

Could Vitamin D Become a Precision Treatment?

Potentially—but probably not as simple supplementation.

The new 2026 study suggests that specific metabolic pathways such as:

TK1 → PFKFB3 → glycolysis

could potentially become therapeutic targets. (PubMed)

Future research may therefore focus on:

• VDR agonists

• fibroblast metabolism

• PFKFB3

• vitamin D-responsive molecular phenotypes

rather than simply giving higher doses of conventional vitamin D.

Why Randomized Trials Are Needed

The ideal clinical trial would enroll patients with:

• confirmed pulmonary fibrosis

• documented vitamin D deficiency

and randomize them to standardized replacement versus appropriate control.

Important outcomes would include:

• FVC decline

• DLCO

• HRCT fibrosis

• exercise capacity

• quality of life

• exacerbations

• survival

It should also evaluate whether outcomes differ according to:

• IPF versus autoimmune ILD

• baseline vitamin D level

• VDR genetics

• antifibrotic therapy

• immune phenotype

Until such trials are performed, vitamin D remains a promising biological factor rather than a proven disease-modifying therapy.

Functional and Integrative Medicine Perspective

Vitamin D is highly relevant to integrative pulmonary care—but precision in interpretation is essential.

A reasonable comprehensive assessment may consider:

• serum 25(OH)D

• nutritional intake

• bone health

• muscle mass

• physical activity

• gastrointestinal absorption

• medications

• autoimmune disease

If deficiency is present, it should be appropriately addressed.

But correcting deficiency should be presented as:

optimizing nutritional and musculoskeletal health

rather than:

treating pulmonary fibrosis with vitamin D.

This distinction protects patients from unrealistic expectations while still recognizing potentially important modifiable factors.

What We Know

We know that vitamin D:

• has immunomodulatory biological effects

• influences fibroblast biology experimentally

• can reduce experimental pulmonary fibrosis

• is frequently low in chronic respiratory disease

• has been associated with FVC, DLCO and mortality in IPF observational research

• is associated with SSc-ILD occurrence in recent meta-analysis

• can suppress TK1/PFKFB3-driven glycolysis and fibroblast activation experimentally

(PubMed)

What We Do Not Know

We do not know whether vitamin D supplementation:

• slows FVC decline in IPF

• improves DLCO

• prevents fibrosis progression

• reverses established fibrosis

• reduces mortality

• improves SSc-ILD

• enhances antifibrotic treatment

These remain unanswered clinical questions.

What Does This Mean Clinically?

The most evidence-based interpretation is:

Vitamin D deficiency should be identified and appropriately corrected for established nutritional, bone and musculoskeletal reasons, particularly in patients with chronic lung disease.

But vitamin D supplementation should not currently be presented as an antifibrotic therapy.

This approach recognizes the biological evidence without exceeding it.

Frequently Asked Questions

Is vitamin D deficiency common in pulmonary fibrosis?

Low vitamin D levels have been reported in IPF and other chronic respiratory diseases, although prevalence varies between populations.

Is low vitamin D associated with worse IPF?

Yes. Observational research has linked vitamin D deficiency with lower FVC and DLCO, greater disease severity and increased mortality. (PubMed)

Does that mean vitamin D deficiency causes pulmonary fibrosis?

No. Association does not establish causation.

Can vitamin D reverse pulmonary fibrosis?

There is currently no human clinical evidence that vitamin D supplementation reverses established pulmonary fibrosis.

Does vitamin D reduce fibrosis in animals?

Yes. Experimental studies have demonstrated antifibrotic effects.

What did the new 2026 study find?

It found that vitamin D inhibited fibroblast activation and experimental pulmonary fibrosis partly by suppressing TK1/PFKFB3-driven glycolysis. (PubMed)

Is vitamin D linked with systemic sclerosis-associated ILD?

A recent meta-analysis found lower vitamin D levels associated with the occurrence of ILD in systemic sclerosis. (PubMed)

Should patients with pulmonary fibrosis check vitamin D?

Vitamin D assessment can be clinically appropriate, particularly when there are risk factors for deficiency, poor nutrition, osteoporosis, reduced sunlight exposure or other indications.

What vitamin D level stops fibrosis?

No such level has been established.

Should patients take high-dose vitamin D for IPF?

High-dose vitamin D should not be used as an unproven treatment for IPF. Excess vitamin D can cause toxicity.

Key Takeaway

Vitamin D is biologically interesting in pulmonary fibrosis.

Experimental evidence suggests that it can influence:

fibroblast activation + TGF-β signaling + cellular metabolism + inflammatory pathways

and newer research has identified TK1/PFKFB3-mediated glycolysis as another potential mechanism. (PubMed)

Human observational studies also associate low vitamin D with poorer IPF outcomes.

But the missing piece remains the most clinically important one:

we do not yet have convincing human trial evidence that vitamin D supplementation slows pulmonary fibrosis.

Conclusion

Vitamin D occupies an interesting position between nutritional medicine and pulmonary fibrosis biology.

It is clearly more than a regulator of calcium and bone metabolism.

Vitamin D receptors are widely distributed, and vitamin D can influence immune signaling, fibroblast behavior, cellular metabolism and potentially several pathways involved in fibrosis.

Human observational evidence has provided important signals.

One IPF study found vitamin D deficiency associated with lower FVC, lower DLCO, greater GAP disease severity and substantially higher all-cause mortality. (PubMed)

In systemic sclerosis, a recent systematic review and meta-analysis found that lower vitamin D levels were associated with the occurrence of ILD as well as other markers of disease severity. (PubMed)

The experimental evidence has also continued to evolve.

Most notably, a 2026 study identified a novel metabolic pathway through which vitamin D suppressed fibroblast activation:

Vitamin D
→ inhibition of TK1
→ reduction in PFKFB3-driven glycolysis
→ decreased fibroblast activation
→ reduced experimental fibrosis. (PubMed)

This is particularly interesting because modern pulmonary fibrosis research increasingly recognizes metabolic reprogramming of fibroblasts as part of fibrogenesis.

But the clinical evidence remains behind the mechanistic science.

The European Respiratory Society’s 2026 review of vitamin D in pulmonary disease emphasized this wider problem: observational and mechanistic studies frequently suggest benefit, while randomized clinical trial evidence remains inconsistent. (PubMed)

Therefore, the most scientifically defensible conclusion is not that vitamin D “treats pulmonary fibrosis.”

It is that:

vitamin D deficiency may represent an important biological, nutritional and prognostic factor that deserves appropriate assessment in patients with chronic lung disease, while its role as a disease-modifying treatment remains unproven.

For patients with pulmonary fibrosis, correcting genuine deficiency may support:

• bone health

• muscle function

• nutritional status

• rehabilitation

• overall health

These outcomes matter.

But vitamin D should not replace established treatment such as antifibrotic therapy for appropriate patients with IPF or immunomodulatory treatment for selected autoimmune-associated ILD.

The next phase of research should determine whether carefully selected vitamin D-deficient pulmonary fibrosis patients represent a phenotype in which targeted correction produces measurable pulmonary benefit.

Until then, the appropriate approach is:

test when clinically appropriate, correct deficiency responsibly, and avoid turning promising mechanistic evidence into an unproven antifibrotic claim.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical and academic interests include Integrative and Functional Pulmonology, pulmonary fibrosis, autoimmune-associated ILD, the gut–lung axis, nutrition, metabolic health and emerging microbiome research.

Looking for a Comprehensive Approach to Pulmonary Fibrosis or ILD?

A comprehensive assessment of pulmonary fibrosis may include not only the lung disease itself, but also clinically relevant factors such as:

• nutritional status

• vitamin and mineral deficiencies

• gastrointestinal health

• reflux

• muscle mass

• metabolic health

• lifestyle factors

These factors should be addressed alongside—not instead of—appropriate pulmonary and rheumatological treatment.

Contact us through the consultation page or WhatsApp to learn more about online consultation options.

Functional and integrative care should complement—not replace—evidence-based pulmonary treatment.

Medical Disclaimer: This article is for educational purposes only and does not constitute individualized medical advice. Vitamin D is not currently an established treatment for pulmonary fibrosis.

GERD, Microaspiration and Pulmonary Fibrosis: Can Reflux Affect Lung Fibrosis?

Gastroesophageal reflux disease, or GERD, is surprisingly common in people with pulmonary fibrosis.

For years, researchers have questioned whether this relationship is simply coincidence or whether repeated reflux and microaspiration could contribute to ongoing lung injury.

The biological hypothesis sounds reasonable:

stomach contents reflux into the esophagus
↓
small amounts reach the throat or airway
↓
microaspiration occurs
↓
repeated epithelial injury develops
↓
fibrotic pathways may be activated

But the clinical evidence is much more complicated.

GERD is unquestionably common in idiopathic pulmonary fibrosis.

A major systematic review and meta-analysis published in June 2026 analyzed 33 studies involving 35,807 patients with IPF and estimated the pooled prevalence of GERD at approximately 47%. (PubMed)

Older physiological studies have reported even higher rates of abnormal reflux when patients undergo objective reflux testing.

But a high prevalence of GERD does not prove that reflux causes pulmonary fibrosis.

Nor has treating reflux convincingly been shown to slow IPF progression.

In fact, current international IPF guidelines recommend against using antacid medication solely for the purpose of improving respiratory outcomes in IPF, while still recognizing that GERD should be treated when there is a conventional gastrointestinal indication. (PubMed Central (PMC))

So where does this leave the reflux–lung hypothesis?

The most accurate interpretation is:

GERD and pulmonary fibrosis are strongly associated, microaspiration remains biologically plausible as a contributor to lung injury, but reflux has not been established as a primary cause of IPF and antacid therapy has not been proven to modify IPF progression.

The relationship becomes even more interesting in systemic sclerosis-associated ILD, where esophageal dysmotility, reflux and impaired clearance are extremely common.

This article examines the latest evidence.

What Is GERD?

Gastroesophageal reflux occurs when stomach contents travel upward into the esophagus.

Occasional reflux can occur normally.

GERD refers to reflux that causes troublesome symptoms, mucosal injury or other complications.

Typical symptoms include:

• heartburn

• acid regurgitation

• sour taste

• chest discomfort

But reflux does not always cause classic symptoms.

Some people experience:

• chronic cough

• hoarseness

• throat clearing

• throat irritation

• nocturnal symptoms

Others may have significant abnormal reflux on physiological testing without obvious symptoms at all.

This is particularly relevant to pulmonary fibrosis.

What Is Silent Reflux?

The term silent reflux is often used when clinically significant reflux occurs without classic heartburn or regurgitation.

In pulmonary disease, this matters because relying exclusively on symptoms can miss abnormal reflux.

Historical IPF studies found that many patients with abnormal reflux did not report typical GERD symptoms.

This is one reason investigators became interested in reflux as a potentially overlooked contributor to chronic pulmonary injury.

What Is Microaspiration?

Aspiration occurs when material enters the respiratory tract instead of remaining within the digestive tract.

Large-volume aspiration can cause obvious respiratory illness.

Microaspiration refers to much smaller amounts of material repeatedly entering the airway.

Potential aspirated material may include:

• gastric acid

• pepsin

• bile acids

• food particles

• oral secretions

• bacteria

Repeated microaspiration may not produce an obvious choking event.

The exposure may be subtle.

This is the biological mechanism most commonly proposed to connect GERD with pulmonary fibrosis.

Why Could Microaspiration Affect the Lungs?

The alveolar epithelium is delicate.

Repeated exposure to gastric or esophageal contents could theoretically cause:

• epithelial injury

• oxidative stress

• inflammatory signaling

• altered epithelial repair

• macrophage activation

Pulmonary fibrosis already involves repeated alveolar epithelial injury followed by abnormal repair.

Therefore, researchers have hypothesized that recurrent aspiration might act as one of several possible epithelial insults.

A simplified model is:

GERD
↓
proximal reflux
↓
microaspiration
↓
alveolar epithelial injury
↓
abnormal repair
↓
fibroblast activation
↓
fibrosis

This is a plausible mechanism.

But plausibility is not the same as proof.

How Common Is GERD in Idiopathic Pulmonary Fibrosis?

Very common.

The most updated quantitative evidence comes from the 2026 systematic review and meta-analysis evaluating 33 studies and 35,807 patients with IPF.

The pooled prevalence of GERD was:

47.0%

with substantial variability between studies. (PubMed)

The investigators also found variations according to:

• study design

• geography

• time period

• methods used to diagnose GERD

This matters because GERD prevalence depends heavily on how it is measured.

Questionnaire-based diagnosis may identify a different group of patients from physiological reflux monitoring.

Why Have Older Studies Reported GERD Rates as High as 90%?

Some older IPF studies using objective esophageal testing reported abnormal acid reflux in very high proportions of patients.

This led earlier international guidelines to consider reflux potentially important in IPF.

The 2015 guideline noted that abnormal acid GER had been observed in up to approximately 90% of selected IPF populations. (OUP Academic)

However, these studies often involved:

• small cohorts

• selected patients

• different definitions of reflux

• varying diagnostic methods

Therefore, a single percentage should not be applied to every patient with IPF.

The newer 2026 meta-analysis provides a broader estimate across a much larger patient population. (PubMed)

Does GERD Cause Idiopathic Pulmonary Fibrosis?

This has not been established.

Several possibilities could explain the association.

Possibility 1: Reflux contributes to pulmonary injury

Repeated microaspiration could injure alveolar epithelial cells and amplify fibrosis.

Possibility 2: Pulmonary fibrosis causes reflux

Fibrotic lungs become stiff.

Changes in intrathoracic pressure mechanics may potentially promote reflux.

Chronic cough may also increase abdominal and thoracic pressure changes.

Possibility 3: Shared risk factors influence both

Age, obesity, hiatal hernia and medications may influence GERD and pulmonary disease independently.

Possibility 4: The relationship is bidirectional

This is probably the most realistic model.

Pulmonary fibrosis may increase reflux susceptibility, while reflux and aspiration may provide additional pulmonary epithelial injury in selected patients.

What Is the Evidence for Microaspiration in IPF?

Directly demonstrating repeated microaspiration is difficult.

Researchers have explored several approaches, including measurement of:

• pepsin

• bile acids

• reflux episodes

• proximal reflux

in association with pulmonary disease.

The presence of gastric components in respiratory samples provides biological evidence that material originating in the stomach can reach the respiratory tract.

But determining whether this causes progressive fibrosis is considerably more difficult.

A patient may aspirate because advanced lung disease alters mechanics.

Therefore, even documented aspiration does not automatically establish the direction of causality.

Acid Reflux Is Only Part of the Story

One major limitation of the early GERD hypothesis is its focus on stomach acid.

Refluxate can also be:

• weakly acidic

• non-acid

• gaseous

• mixed with bile or digestive enzymes

This matters because proton-pump inhibitors decrease gastric acid production.

They do not necessarily stop reflux itself.

A person receiving a PPI may continue to experience:

stomach contents moving upward

but the refluxate may simply contain less acid.

This has major implications for pulmonary disease.

PPIs Do Not Prevent Microaspiration Mechanically

Proton-pump inhibitors such as omeprazole or esomeprazole primarily reduce acid production.

They do not correct:

• hiatal hernia

• weak lower esophageal sphincter

• absent esophageal contractility

• delayed gastric emptying

Therefore:

acid suppression ≠ elimination of reflux

and:

acid suppression ≠ guaranteed prevention of aspiration.

This helps explain why trials of antacid treatment have not definitively established pulmonary benefit.

What Did Earlier IPF Guidelines Recommend?

The recommendations have changed over time.

Earlier guidelines suggested treating asymptomatic reflux in many patients with IPF.

That recommendation was based largely on:

• high prevalence of GERD

• biological plausibility of microaspiration

• retrospective observational studies suggesting possible benefit

The quality of evidence was very low.

As more data accumulated, the recommendation changed.

What Do Current IPF Guidelines Say?

The 2022 ATS/ERS/JRS/ALAT clinical practice guideline states:

patients with IPF should not routinely receive antacid medication solely for the purpose of improving respiratory outcomes.

This is a conditional recommendation based on very low-quality evidence. (PubMed Central (PMC))

However, the guideline makes an equally important point:

patients who have symptomatic GERD can still receive appropriate GERD therapy according to conventional GERD indications.

Therefore, the recommendation is not:

“Do not treat reflux in IPF.”

The recommendation is:

Do not prescribe antacid medication solely because you expect it to slow IPF.

Why Did the Recommendation Change?

Early observational studies suggested possible benefit from antacid therapy.

But subsequent analyses did not consistently demonstrate improvement in clinically important IPF outcomes.

Potential concerns with chronic acid suppression also became relevant.

These can include altered:

• gastrointestinal microbial ecology

• infection susceptibility

• nutrient absorption

depending on the patient and duration of therapy.

Therefore, the balance of evidence no longer supported universal antacid therapy solely for pulmonary purposes.

What Does the Newer Mortality Evidence Show?

A 2025 systematic review and meta-analysis examined antireflux therapy and mortality in patients with IPF and GERD.

Six studies involving 2,874 patients were included.

Antireflux therapy did not produce a statistically significant reduction in overall mortality.

For IPF-related mortality, the pooled estimate suggested a possible benefit, but the confidence interval crossed the threshold for statistical significance.

The authors concluded that more rigorous randomized trials are required. (PubMed)

This reinforces the current position:

the possibility of benefit remains unresolved, but it is not proven.

What About Antireflux Surgery?

If reflux itself rather than acidity is the relevant pulmonary exposure, mechanically preventing reflux could theoretically be more meaningful than acid suppression.

This has generated interest in procedures such as fundoplication.

However, surgical antireflux treatment has not been definitively established as disease-modifying therapy for IPF.

Surgical decisions also require careful assessment of:

• esophageal motility

• aspiration risk

• operative risk

• overall pulmonary status

This becomes particularly complicated in patients with advanced ILD.

Why Is Esophageal Motility Important?

Normal reflux clearance depends partly on effective esophageal contractions.

If the esophagus cannot efficiently push refluxed material back toward the stomach, exposure becomes prolonged.

This is particularly important in systemic sclerosis.

Systemic Sclerosis: A Different Reflux–Lung Scenario

The relationship between reflux and ILD may be particularly relevant in systemic sclerosis, or SSc.

Gastrointestinal involvement is extremely common.

Patients may develop:

• weak or absent esophageal contractions

• lower esophageal sphincter dysfunction

• delayed gastric emptying

• reflux

• esophageal dilation

• SIBO

This creates a strong physiological basis for prolonged reflux and possible microaspiration.

How Common Is GERD in Systemic Sclerosis-ILD?

A large recent analysis from the EUSTAR cohort included 5,462 patients with systemic sclerosis-associated ILD.

GERD was present in approximately:

80.6%

of those patients.

Patients with GERD had:

• lower FVC

• lower DLCO

• poorer six-minute walk performance

• more severe systemic disease

compared with SSc-ILD patients without GERD. (PubMed Central (PMC))

This is a striking association.

But once again:

association does not prove that reflux caused the worse ILD.

Does Reflux Predict SSc-ILD Progression?

The relationship remains complex.

Data from the Scleroderma Lung Study II cohort found that greater reflux symptom severity was independently associated with greater radiological progression of ILD and fibrosis over two years.

Interestingly, objective CT measurements of esophageal dilation were not associated with progression. (PubMed Central (PMC))

This suggests that esophageal involvement may matter, but the optimal marker of pulmonary risk is not yet clear.

Esophageal Dysmotility and Pulmonary Disease

Recent data continue to show relationships between severe esophageal motor dysfunction and pulmonary involvement in systemic sclerosis.

A 2025 analysis reported that esophageal dysmotility was associated with ILD and lower gas-transfer measures, while acknowledging that the direction of causality remains uncertain. (PubMed Central (PMC))

The proposed mechanism is:

dysmotility
↓
poor reflux clearance
↓
more proximal reflux
↓
greater aspiration opportunity
↓
possible lung injury

But the reverse relationship may also contribute.

Reduced lung compliance may modify intrathoracic mechanics and worsen reflux.

Why PPIs May Not Be Enough in Systemic Sclerosis

This is particularly important.

The main problem in systemic sclerosis may not simply be excessive acid.

It may be:

impaired motility and impaired clearance.

A recent study of patients with systemic sclerosis undergoing detailed physiology while taking twice-daily PPIs found:

• GERD remained highly prevalent

• esophageal dysmotility occurred in 80%

• absent contractility was common

• gastric dysmotility was also frequent

Poor esophageal clearance was associated with longer reflux exposure, while gastric dysmotility was associated with greater reflux burden. (PubMed Central (PMC))

This highlights an important clinical principle:

acid suppression may not fully address reflux when the fundamental problem is dysmotility.

Acid Versus Non-Acid Reflux

This is why pH testing alone may be insufficient in selected patients.

A person taking a PPI may have:

• normal acid exposure

• continued non-acid reflux

If the pulmonary concern is aspiration of gastric contents rather than acid exposure alone, non-acid reflux becomes relevant.

Testing that combines:

pH monitoring + impedance

can detect both acid and non-acid reflux episodes.

What Tests Can Evaluate Reflux?

Depending on the clinical problem, assessment may include:

Upper endoscopy

Can identify:

• erosive esophagitis

• Barrett’s esophagus

• structural lesions

But normal endoscopy does not exclude reflux.

Ambulatory pH monitoring

Measures acid exposure.

pH-impedance monitoring

Measures both acid and non-acid reflux and can characterize reflux episodes more comprehensively.

High-resolution esophageal manometry

Assesses:

• esophageal contractility

• sphincter function

• motility disorders

This may be particularly valuable in systemic sclerosis.

Does a Hiatal Hernia Matter?

Hiatal hernia can promote reflux by altering the anatomy of the gastroesophageal junction.

Hiatal hernia is relatively common in patients with IPF.

But its presence does not prove aspiration or determine whether reflux is contributing to fibrosis.

It should be interpreted within the full clinical context.

Can Chronic Cough Be Caused by Reflux?

Yes, reflux can contribute to chronic cough in selected patients.

But cough in pulmonary fibrosis has many possible mechanisms.

These include:

• mechanical distortion of the lungs

• airway hypersensitivity

• fibrosis-related neural changes

• GERD

• upper airway disease

• medications

Therefore, cough should not automatically be attributed to reflux.

Could Treating Reflux Improve Cough Without Changing Fibrosis?

Yes.

This distinction is important.

A patient may experience improvement in:

• heartburn

• regurgitation

• nocturnal cough

after treating GERD.

That is clinically useful.

But symptom improvement does not necessarily mean that lung fibrosis has slowed.

Gastrointestinal outcomes and pulmonary fibrosis outcomes should be assessed separately.

Where Does the Gut Microbiome Fit Into This?

GERD and the gut–lung axis are related but distinct concepts.

The reflux–lung pathway is primarily:

stomach/esophagus
→ reflux
→ microaspiration
→ lung

The gut microbiome–lung pathway is primarily:

intestinal microbiome
→ microbial metabolites and immune signaling
→ systemic circulation
→ lung

Both may influence respiratory disease.

But they should not be combined into one mechanism.

Could PPIs Influence the Gut Microbiome?

Yes.

Proton-pump inhibitors can alter intestinal microbial composition.

This is relevant because the 2026 CleanUP-IPF microbiome study found that PPI use itself was associated with gut microbiome characteristics in patients with IPF. (PubMed)

This creates an important research challenge.

If a study finds dysbiosis in IPF, researchers need to distinguish microbial effects related to:

• IPF itself

• age

• diet

• PPI exposure

• antibiotics

• other medications

This is one reason microbiome associations must be interpreted cautiously.

Does This Mean PPIs Should Be Avoided?

No.

A medication should not be stopped simply because it may influence the microbiome.

PPIs have established indications.

They can be highly effective in:

• erosive esophagitis

• symptomatic GERD

• selected Barrett’s esophagus management

• other acid-related disorders

The appropriate question is:

Does this patient have a good indication for the medication?

not:

Does the medication change gut bacteria?

Functional and Integrative Medicine Perspective

GERD is an area where integrative evaluation can be useful—provided it remains physiologically grounded.

Instead of assuming all reflux is caused by “too much stomach acid,” evaluation should consider:

• lower esophageal sphincter function

• hiatal hernia

• esophageal dysmotility

• gastric emptying

• meal timing

• body weight

• nocturnal reflux

• medications

• food triggers

In systemic sclerosis, motility deserves particular attention.

Lifestyle Measures for GERD

Depending on the patient, supportive strategies may include:

• avoiding large meals close to bedtime

• remaining upright after meals

• identifying individual food triggers

• reducing excess body weight where appropriate

• elevating the head of the bed for nocturnal reflux

These strategies may improve reflux symptoms.

They have not been proven to reverse pulmonary fibrosis.

Should Everyone With Pulmonary Fibrosis Be Tested for GERD?

Not necessarily.

Testing should depend on the clinical context.

Potential reasons for further assessment may include:

• troublesome reflux symptoms

• unexplained regurgitation

• significant nocturnal symptoms

• recurrent aspiration suspicion

• dysphagia

• systemic sclerosis with severe esophageal involvement

• evaluation before lung transplantation

The appropriate investigation varies between patients.

Reflux and Lung Transplantation

GERD and aspiration are also important considerations in lung transplantation.

After transplantation, aspiration and reflux may potentially contribute to allograft injury.

Many transplant programs therefore pay close attention to:

• reflux

• aspiration

• esophageal motility

• gastric emptying

This is a distinct clinical context from native-lung IPF, but it reinforces how closely gastrointestinal physiology can interact with pulmonary health.

What We Know

Current evidence supports several conclusions.

We know that:

• GERD is common in IPF

• a 2026 meta-analysis estimated GERD prevalence around 47% across more than 35,000 patients

• reflux may occur without typical symptoms

• microaspiration is biologically capable of injuring lung tissue

• GERD and severe esophageal dysfunction are highly prevalent in SSc-ILD

• greater reflux burden or symptoms have been associated with worse pulmonary disease in several observational SSc studies

(PubMed)

What We Do Not Know

We do not know:

• whether GERD causes IPF

• how much microaspiration contributes to IPF progression

• which IPF patients are most vulnerable to aspiration-mediated injury

• whether treating reflux slows FVC decline

• whether acid or non-acid reflux is more important

• whether antireflux surgery improves long-term IPF outcomes

• whether reflux is a cause or consequence of more severe SSc-ILD

What Does This Mean Clinically?

The practical approach is not to ignore reflux.

Nor is it to assume that every patient with pulmonary fibrosis needs a PPI.

Instead:

identify clinically meaningful reflux or dysmotility
→ characterize the mechanism when necessary
→ treat GERD appropriately
→ continue evidence-based ILD therapy

Treatment of reflux should be directed toward its established gastrointestinal or aspiration-related indications.

It should not be presented as a replacement for antifibrotic or immunomodulatory therapy.

What Treatments Still Matter for IPF?

Depending on the patient, evidence-based pulmonary care may include:

• antifibrotic therapy

• oxygen when indicated

• pulmonary rehabilitation

• vaccination

• treatment of comorbidities

• lung transplantation evaluation

Reflux management should complement this framework.

What About Autoimmune ILD?

In autoimmune ILD, especially systemic sclerosis, the gastrointestinal component may deserve more active assessment.

Potentially relevant issues include:

• esophageal dysmotility

• severe GERD

• delayed gastric emptying

• SIBO

• nutritional compromise

• swallowing dysfunction

But management should remain individualized.

Frequently Asked Questions

Can acid reflux cause pulmonary fibrosis?

There is no definitive evidence that GERD causes idiopathic pulmonary fibrosis.

Repeated microaspiration is a biologically plausible contributor to lung injury, but causality remains unproven.

How common is GERD in IPF?

A 2026 meta-analysis of 33 studies involving 35,807 patients estimated the prevalence at approximately 47%. (PubMed)

Can you have reflux without heartburn?

Yes.

Some patients have clinically significant reflux without typical heartburn or regurgitation.

What is microaspiration?

Microaspiration refers to small amounts of oral, esophageal or gastric material entering the respiratory tract, often without an obvious choking episode.

Does taking a PPI prevent aspiration?

Not necessarily.

PPIs reduce gastric acidity but do not mechanically stop reflux.

Should all patients with IPF take PPIs?

No.

Current international guidelines suggest against prescribing antacid therapy solely to improve respiratory outcomes in IPF. PPIs remain appropriate when there is a separate GERD indication. (PubMed Central (PMC))

Can treating reflux reverse pulmonary fibrosis?

No clinical evidence demonstrates that treating GERD reverses established pulmonary fibrosis.

Is reflux important in systemic sclerosis-ILD?

Yes.

GERD and esophageal dysmotility are extremely common in systemic sclerosis, and observational studies have linked reflux with more severe pulmonary involvement. (PubMed Central (PMC))

How can non-acid reflux be detected?

Combined pH-impedance monitoring can detect acid and non-acid reflux.

Can diet help reflux?

Meal timing, avoiding individual triggers, weight management where appropriate and other lifestyle strategies can help selected patients with GERD.

They have not been proven to alter pulmonary fibrosis progression.

Key Takeaway

The most accurate interpretation is:

GERD is common in pulmonary fibrosis and repeated microaspiration is a biologically plausible source of additional lung injury, but current evidence does not prove that GERD causes IPF or that routine antacid treatment slows pulmonary fibrosis.

Conclusion

The relationship between GERD, microaspiration and pulmonary fibrosis remains one of the most intriguing and debated areas in interstitial lung disease.

GERD is clearly common in IPF.

The most recent large systematic review, published in 2026 and including 35,807 patients, estimated that approximately 47% of patients with IPF have GERD. (PubMed)

The biological rationale linking reflux with pulmonary fibrosis is also credible.

Repeated proximal reflux may permit small amounts of gastric or esophageal material to enter the respiratory tract.

That exposure could theoretically contribute to:

• epithelial injury

• inflammation

• abnormal repair

• fibroblast activation

But important questions remain unanswered.

We do not know whether reflux initiates IPF.

We do not know how much microaspiration contributes to disease progression.

And we have not demonstrated that routinely suppressing gastric acid improves meaningful pulmonary outcomes.

This is why current international guidelines recommend against using antacid medication solely to improve respiratory outcomes in IPF, while continuing to support appropriate treatment of symptomatic GERD. (PubMed Central (PMC))

Systemic sclerosis presents a different and particularly important scenario.

Large contemporary cohorts show GERD in the majority of patients with SSc-ILD, while reflux severity and esophageal dysfunction are associated with more severe pulmonary disease in observational studies. (PubMed Central (PMC))

Recent physiological research also demonstrates why acid suppression alone may sometimes be inadequate in systemic sclerosis: severe esophageal and gastric dysmotility can cause persistent reflux even during intensive PPI therapy. (PubMed)

This points toward a more sophisticated clinical model.

Instead of asking simply:

“Does the patient have too much stomach acid?”

we may need to ask:

“Is reflux occurring, how proximal is it, is it acid or non-acid, is esophageal clearance impaired, is gastric emptying abnormal, and is there reason to suspect aspiration?”

That framework is especially important in autoimmune ILD and lung transplantation.

The reflux–lung relationship also needs to be distinguished from the gut–lung microbiome axis.

Reflux primarily creates a potential physical route of exposure from the gastrointestinal tract to the lung through aspiration.

The microbiome pathway primarily involves immune and metabolic communication between intestinal microbes and distant organs.

Both may eventually prove relevant to pulmonary fibrosis.

But they represent different mechanisms and require different clinical approaches.

For now, the appropriate strategy is balanced:

identify and treat clinically important reflux and gastrointestinal dysfunction while continuing evidence-based pulmonary fibrosis care.

Reflux management may improve gastrointestinal symptoms and potentially reduce aspiration exposure.

What has not yet been demonstrated is that it can replace—or reliably enhance—the disease-modifying treatment of pulmonary fibrosis.

Future studies combining:

• pH-impedance monitoring

• esophageal manometry

• aspiration biomarkers

• lung microbiome analysis

• HRCT progression

• pulmonary function

may eventually identify the subgroup of patients in whom reflux truly acts as a pulmonary disease modifier.

That would move the field from a general association toward precision treatment.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical and academic interests include Integrative and Functional Pulmonology, pulmonary fibrosis, autoimmune-associated ILD, the gut–lung axis, gastrointestinal–pulmonary interactions, nutrition and emerging microbiome science.

Looking for a Comprehensive Approach to Pulmonary Fibrosis or ILD?

If you are living with pulmonary fibrosis, systemic sclerosis-associated ILD or another form of interstitial lung disease and would like a comprehensive assessment that considers your pulmonary condition together with relevant reflux, gastrointestinal, nutritional, metabolic and lifestyle factors, online consultation options are available.

The goal is to integrate these factors with—not replace—established pulmonary and rheumatological care.

Contact us through the consultation page or WhatsApp to learn more.

Functional and integrative care is intended to complement—not replace—appropriate evidence-based pulmonary treatment.

Medical Disclaimer: This article is intended for educational purposes only and does not constitute individualized medical advice. Patients with pulmonary fibrosis or interstitial lung disease should remain under appropriate specialist care.

Related Topics

• Gut–Lung Axis and Pulmonary Fibrosis

• Gut Dysbiosis and Pulmonary Fibrosis

• Leaky Gut and Pulmonary Fibrosis

• Gut Microbiome and Systemic Sclerosis-Associated ILD

• SIBO and Systemic Sclerosis

• Can Diet Change the Gut Microbiome in Pulmonary Fibrosis?

• Can the Gut Microbiome Become a Therapeutic Target in Pulmonary Fibrosis?

Leaky Gut and Pulmonary Fibrosis: Is There Scientific Evidence?

Could a problem in the intestinal barrier influence what happens in the lungs?

It may sound surprising, especially in a disease such as pulmonary fibrosis, where the most visible pathology occurs deep within the lung.

Yet this question is increasingly being investigated.

The intestine contains trillions of microorganisms and has one of the largest interfaces between the external environment and the immune system. A highly regulated intestinal barrier normally separates this microbial ecosystem from the systemic circulation.

When that barrier becomes dysfunctional, microbial products may gain greater access to the bloodstream.

This phenomenon is often described as increased intestinal permeability and is commonly referred to outside scientific literature as “leaky gut.”

Researchers are now studying whether intestinal-barrier dysfunction could contribute to diseases far beyond the gastrointestinal tract.

Pulmonary fibrosis is one of them.

Experimental pulmonary fibrosis studies have demonstrated intestinal microbiome disruption, changes in tight-junction proteins and evidence of intestinal-barrier dysfunction. A major 2025 review of the lung–gut axis identified barrier dysfunction as one of five core mechanisms potentially linking microbial dysbiosis with pulmonary fibrosis. (Frontiers)

But there is an important limitation.

Most direct evidence connecting increased intestinal permeability with pulmonary fibrosis comes from animal and mechanistic studies—not from patients with idiopathic pulmonary fibrosis.

This distinction matters.

It means we can reasonably discuss leaky gut as an emerging biological hypothesis in pulmonary fibrosis.

We cannot currently say that leaky gut causes IPF or that repairing the intestinal barrier will stop or reverse pulmonary fibrosis.

So what does the evidence actually show?

What Does “Leaky Gut” Actually Mean?

The medical term most closely corresponding to “leaky gut” is:

increased intestinal permeability.

The intestine is lined by a single layer of epithelial cells.

These cells are joined together by structures known as tight junctions, which help control what passes from the intestinal lumen into the circulation.

Important tight-junction proteins include:

• zonula occludens-1, or ZO-1

• occludin

• claudins

Under normal conditions, this barrier allows nutrients and selected molecules to cross while restricting excessive entry of:

• bacteria

• bacterial fragments

• endotoxins

• microbial antigens

• other potentially inflammatory substances

When intestinal-barrier integrity becomes impaired, the movement of these substances across the intestinal lining may increase.

This is what researchers mean by increased intestinal permeability.

Is “Leaky Gut” a Diagnosis?

Not in the same way that conditions such as Crohn’s disease, celiac disease or ulcerative colitis are diagnoses.

The phrase leaky gut syndrome is often used very broadly in wellness and functional medicine settings.

That can create confusion.

Intestinal permeability is a real physiological phenomenon and can be measured in research settings.

But it is not currently an established explanation for every chronic inflammatory or autoimmune condition.

The important question is not whether intestinal permeability exists.

It clearly does.

The important question is:

Does abnormal intestinal permeability meaningfully contribute to a particular disease?

For pulmonary fibrosis, that question remains under investigation.

Why Might the Gut Barrier Matter to the Lungs?

The intestine and lungs communicate through the gut–lung axis.

This communication occurs through several systems:

• immune cells

• circulating inflammatory mediators

• microbial metabolites

• microbial components

• bone-marrow immune responses

A simplified proposed pathway is:

Gut dysbiosis
↓
Reduced intestinal-barrier integrity
↓
Greater exposure to microbial products
↓
Systemic immune activation
↓
Pulmonary epithelial and immune-cell signaling
↓
Potential influence on fibrotic pathways

This pathway is biologically plausible.

But each step requires evidence.

What Is Pulmonary Fibrosis?

Pulmonary fibrosis refers to abnormal accumulation of scar tissue within the lungs.

In idiopathic pulmonary fibrosis, or IPF, the process appears to involve repeated injury to alveolar epithelial cells followed by abnormal repair.

Major biological processes include:

• epithelial injury

• cellular senescence

• fibroblast activation

• myofibroblast differentiation

• TGF-β signaling

• extracellular matrix deposition

• collagen accumulation

Over time, normal lung architecture is progressively replaced by fibrotic tissue.

The key question is whether signals originating in the gut might modify this process.

What Does the Current Evidence Say?

Current evidence can be divided into three levels:

1. Human microbiome evidence

Patients with pulmonary fibrosis appear to have alterations in microbial communities.

2. Experimental evidence of intestinal-barrier dysfunction

Animal pulmonary fibrosis models show abnormalities in gut-barrier integrity.

3. Mechanistic evidence

Microbial products and metabolites can influence immune and profibrotic pathways.

The strongest evidence for intestinal permeability specifically currently comes from levels 2 and 3.

Human Evidence: The Gut Microbiome Is Associated With IPF

One important development came in 2026.

Researchers analyzed fecal microbial samples from 411 patients with idiopathic pulmonary fibrosis enrolled in the CleanUP-IPF study.

Gut microbiota were characterized using both 16S rRNA sequencing and shotgun metagenomic sequencing.

The investigators found that gut microbial composition was associated with clinical characteristics including:

• age

• sex

• proton-pump inhibitor use

Importantly, microbial community features were also associated with percent predicted DLCO, an important measure of pulmonary disease severity.

Certain microbial features were additionally associated with transplant-free survival in selected analyses. (PubMed)

This provides strong evidence that the intestinal microbiome is associated with the clinical phenotype of human IPF.

But the study did not demonstrate that those patients had increased intestinal permeability.

That distinction is critical.

Gut Dysbiosis Is Not the Same as Leaky Gut

These terms are frequently used interchangeably, but they describe different biological processes.

Gut dysbiosis

refers to changes in microbial ecology.

Increased intestinal permeability

refers to impaired intestinal-barrier function.

Dysbiosis may contribute to barrier dysfunction.

Barrier dysfunction may also change the microbial ecosystem.

They may occur together.

But demonstrating dysbiosis does not automatically prove increased intestinal permeability.

Therefore, the large 2026 IPF microbiome study strengthens the evidence for a gut–IPF association, but it does not prove “leaky gut” in IPF.

What Do Animal Studies Show?

This is where the evidence becomes more direct.

A 2024 study evaluated intestinal microbiota and signaling pathways in a bleomycin-induced pulmonary fibrosis model.

The animals developed progressive lung injury and fibrosis together with:

• altered intestinal microbial composition

• abnormalities in PI3K/AKT signaling

• abnormalities in NRF2/HO-1 signaling

• intestinal-barrier dysfunction

The investigators concluded that experimental pulmonary fibrosis was associated with both intestinal dysbiosis and intestinal barrier disorder. (PubMed)

This is important because it demonstrates that pulmonary fibrosis and intestinal-barrier abnormalities can occur together in an experimental model.

But again, this was an animal model.

Tight-Junction Proteins in Experimental Pulmonary Fibrosis

Several pulmonary fibrosis models have examined the proteins that maintain intestinal-barrier integrity.

These include:

• ZO-1

• occludin

• claudin-1

Experimental fibrosis has been associated with reduced expression of these proteins.

A 2024 mouse study investigating lung–gut crosstalk reported disruption of both pulmonary and intestinal barriers during bleomycin-induced fibrosis.

An experimental intervention improved expression of:

• ZO-1

• claudin-1

• occludin

in addition to improving lung–gut immune and microbial abnormalities. (PubMed)

This supports the concept that barrier dysfunction can be part of experimental pulmonary fibrosis biology.

Why Do Tight Junctions Matter?

Tight junctions help regulate the passage of substances between intestinal epithelial cells.

If proteins such as ZO-1 and occludin decrease, the intestinal barrier may become more permeable.

That could theoretically allow more:

• lipopolysaccharide

• bacterial fragments

• microbial DNA

• metabolites

to enter systemic circulation.

These substances may then interact with the immune system.

The LPS Hypothesis

One of the most important molecules in this discussion is:

lipopolysaccharide, or LPS.

LPS is part of the outer membrane of Gram-negative bacteria.

When LPS reaches immune cells, it can activate receptors such as:

Toll-like receptor 4, or TLR4.

This can stimulate downstream inflammatory pathways including:

NF-κB

and increase production of inflammatory mediators.

A potential gut–lung pathway is therefore:

Gut dysbiosis
→ impaired barrier
→ increased LPS exposure
→ TLR4 activation
→ inflammatory signaling
→ pulmonary epithelial injury and fibroblast activation

A major 2025 lung–gut fibrosis review identifies LPS as one of the principal microbial mediators potentially linking gut-barrier dysfunction with pulmonary fibrosis. (Frontiers)

This mechanism is plausible.

It is not yet proven as a major driver of human IPF.

Could LPS Activate Fibroblasts?

Potentially.

TLR signaling can interact with pathways relevant to fibrosis.

These include:

• NF-κB

• inflammatory cytokines

• macrophage activation

• TGF-β-related signaling

Fibroblasts respond to their inflammatory and biochemical environment.

Under profibrotic conditions they may differentiate into myofibroblasts and produce greater amounts of extracellular matrix.

This provides a plausible bridge between microbial translocation and fibrotic signaling.

However, the presence of a plausible pathway does not establish how important that pathway is in patients.

The Gut Barrier and Systemic Inflammation

If intestinal permeability increases, systemic exposure to microbial signals may theoretically increase.

This could affect pulmonary immunity through:

• circulating cytokines

• monocyte recruitment

• macrophage activation

• T-cell responses

The lung–gut fibrosis literature has proposed that intestinal-barrier dysfunction can amplify inflammatory signaling involving mediators such as:

• IL-6

• IL-17

• TNF-α

which may influence pulmonary inflammatory and fibrotic pathways. (Frontiers)

Again, much of this evidence is mechanistic or preclinical.

Treg and Th17 Cells

The intestinal microbiome strongly influences immune-cell differentiation.

Two immune populations of particular interest are:

regulatory T cells, or Tregs

and

Th17 cells.

Tregs generally help regulate excessive immune activity.

Th17 cells participate in mucosal defense but can contribute to pathological inflammation when dysregulated.

Changes in the gut microbiome and microbial metabolites may influence the balance between these populations.

A dysbiotic intestinal environment with reduced barrier integrity might theoretically favor more inflammatory immune signaling.

The 2025 pulmonary fibrosis review identifies dysregulated immune balance—including Th17-related pathways—as one mechanism linking microbiota with fibrosis. (PubMed)

Short-Chain Fatty Acids: The Other Side of the Barrier Story

Not all microbial products are potentially harmful.

Many gut bacteria generate metabolites that support intestinal-barrier integrity.

Among the most important are short-chain fatty acids, or SCFAs.

These include:

• acetate

• propionate

• butyrate

SCFAs are produced when intestinal bacteria ferment dietary substrates.

They can influence:

• intestinal epithelial cells

• tight-junction proteins

• Treg activity

• macrophages

• inflammatory signaling

Therefore, intestinal barrier health may depend not simply on preventing harmful bacteria from entering the bloodstream but also on maintaining adequate microbial metabolic function.

Butyrate and the Intestinal Barrier

Butyrate is particularly relevant.

It serves as an important energy source for colonocytes and can help support intestinal epithelial integrity.

Butyrate also influences immune and epigenetic pathways.

If dysbiosis reduces butyrate-producing microbial activity, intestinal-barrier function could theoretically weaken.

This creates another potential pathway:

Dysbiosis
↓
Reduced beneficial microbial metabolites
↓
Barrier impairment
↓
Greater inflammatory exposure
↓
Potential systemic and pulmonary effects

But this remains a mechanistic model.

There is no evidence that simply giving a patient butyrate will repair pulmonary fibrosis.

SCFAs and LPS May Work in Opposite Directions

The emerging literature suggests an important interaction.

SCFAs may help strengthen the intestinal barrier and reduce microbial translocation.

LPS, on the other hand, may promote inflammatory signaling.

The balance between these microbial signals may therefore be more relevant than the abundance of a single bacterial species.

This is one reason modern microbiome research is shifting from asking:

“Which bacteria are present?”

toward:

“What are those microbial communities producing?”

Tryptophan Metabolism May Also Influence the Barrier

Gut bacteria metabolize the amino acid tryptophan into multiple compounds.

Some of these activate the:

aryl hydrocarbon receptor, or AhR.

AhR signaling influences:

• epithelial-barrier integrity

• mucosal immunity

• Treg/Th17 balance

Reduced production of beneficial AhR ligands could theoretically impair intestinal immune homeostasis.

At the same time, pulmonary fibrosis research has shown that tryptophan metabolism can influence fibrotic pathways.

For example, experimental work has demonstrated that tryptophan can promote fibroblast activation and epithelial–mesenchymal signaling through mTOR-related pathways in pulmonary fibrosis models. (Nature)

This demonstrates how gut microbial metabolism, immune regulation and fibrosis could potentially intersect.

The Gut Barrier May Affect the Lung Barrier

Another intriguing concept is that disruption may occur at more than one epithelial surface.

The intestine has a barrier.

The lung also has epithelial and endothelial barriers.

The 2025 pulmonary fibrosis gut–lung review proposes that increased systemic exposure to microbial products can influence pulmonary epithelial and vascular barrier integrity. (Frontiers)

This raises the possibility of a broader:

gut barrier–lung barrier axis.

However, it remains primarily mechanistic.

Lung Tight-Junction Abnormalities Are Better Established Than Gut Permeability in Human IPF

This is an important distinction.

Studies of human IPF lungs have demonstrated abnormalities in pulmonary epithelial tight-junction proteins.

This supports the concept of impaired lung epithelial barrier integrity in IPF.

But this should not be cited as evidence of intestinal permeability.

The lung barrier and gut barrier are different tissues.

One of the common mistakes in gut–lung discussions is to use evidence of altered lung tight junctions as proof that patients have leaky gut.

That conclusion is not justified.

Could the Lung Disease Cause the Leaky Gut Instead?

Yes.

This possibility deserves much more attention.

Suppose a patient with severe pulmonary fibrosis develops intestinal-barrier dysfunction.

It could be caused by the lung disease rather than causing the lung disease.

Advanced pulmonary disease can be accompanied by:

• reduced physical activity

• altered diet

• hypoxemia

• systemic inflammation

• multiple medications

• antibiotic exposure

• proton-pump inhibitor use

All of these can potentially influence gastrointestinal physiology and microbial ecology.

Therefore, the relationship could be:

lung disease → gut dysfunction

rather than simply:

gut dysfunction → lung disease.

The most realistic model may be bidirectional.

Does Leaky Gut Cause IPF?

At present, there is no convincing human evidence that increased intestinal permeability causes idiopathic pulmonary fibrosis.

This statement should be very clear.

We have:

Strong biological plausibility

Yes.

Experimental evidence

Yes.

Evidence of altered gut microbiota in human IPF

Yes.

Large human data showing microbiome associations with disease severity

Yes. (PubMed)

Direct prospective human evidence showing intestinal permeability precedes and causes IPF

No.

That is the current evidence hierarchy.

Is Leaky Gut Associated With Other Fibrotic Lung Diseases?

The broader gut–lung literature includes other fibrotic disorders such as:

• systemic sclerosis-associated ILD

• rheumatoid arthritis-associated ILD

• myositis-associated ILD

• silicosis

• coal workers’ pneumoconiosis

The evidence is particularly interesting in systemic sclerosis because gastrointestinal involvement, dysmotility and SIBO are common.

In such diseases, gut dysfunction may be clinically more prominent than in idiopathic pulmonary fibrosis.

But even there, demonstrating dysbiosis or gastrointestinal disease does not prove that intestinal permeability directly causes pulmonary fibrosis.

What About Systemic Sclerosis?

Systemic sclerosis is particularly relevant to the gut–lung hypothesis.

Patients may experience:

• esophageal dysmotility

• gastroparesis

• small-intestinal dysmotility

• SIBO

• malabsorption

• reflux

Human microbiome research has also identified intestinal microbial patterns associated with SSc-ILD.

This creates a biologically plausible interaction between:

**gut dysmotility

• dysbiosis

• immune dysfunction

• pulmonary disease.**

But the pathway remains complex.

Scleroderma itself can damage both the gastrointestinal tract and lungs.

Therefore, gut abnormalities may be part of systemic disease rather than the primary cause of ILD.

Is Leaky Gut the Same as SIBO?

No.

These are different concepts.

SIBO

refers to abnormal bacterial overgrowth or microbial composition within the small intestine.

Increased intestinal permeability

refers to impaired intestinal-barrier integrity.

Gut dysbiosis

refers more broadly to alteration of microbial ecology.

A person could theoretically have:

• dysbiosis without SIBO

• SIBO without proven increased permeability

• increased permeability without SIBO

They should not automatically be treated as interchangeable diagnoses.

Can Commercial Testing Diagnose Leaky Gut?

This requires caution.

Various laboratory tests have been promoted to evaluate intestinal permeability.

Some research methods assess passage of specific sugar molecules across the intestine.

Commercial testing may also measure markers such as:

• zonulin

• LPS-related markers

• intestinal fatty acid binding protein

• other proposed permeability markers

But none currently functions as an established pulmonary fibrosis biomarker.

There is no validated commercial test that can tell a patient:

“Your pulmonary fibrosis is being caused by leaky gut.”

What About Zonulin?

Zonulin is frequently discussed in functional medicine.

It is involved in regulation of intestinal tight junctions.

However, interpreting commercially measured zonulin is complicated.

Different laboratory assays may not necessarily measure the biologically relevant molecule with adequate specificity.

Therefore, a single elevated commercial zonulin value should not be used to conclude that intestinal permeability is causing pulmonary fibrosis.

Can Treating Leaky Gut Improve Pulmonary Fibrosis?

There is currently no clinical evidence that treating intestinal permeability:

• improves FVC

• improves DLCO

• reverses fibrosis on HRCT

• reduces progressive pulmonary fibrosis

• improves transplant-free survival

This is the critical clinical limitation.

Improving gastrointestinal health may still be worthwhile.

But it should not be presented as a proven antifibrotic therapy.

What About Probiotics?

Probiotics may influence:

• microbial composition

• SCFA production

• intestinal-barrier function

• immune signaling

Animal pulmonary fibrosis experiments have produced encouraging results with selected strains.

But no probiotic has been proven to repair intestinal permeability and thereby slow human IPF.

Probiotic effects are also strain-specific.

One Lactobacillus strain cannot automatically be assumed to have the same effect as another.

What About Prebiotics and Fiber?

Dietary fiber can support microbial fermentation and production of short-chain fatty acids.

This can potentially support intestinal-barrier health.

However, there is no clinical trial showing that increasing fiber slows pulmonary fibrosis.

In addition, not every patient with ILD tolerates high amounts of fermentable fiber.

This is particularly relevant in people with:

• significant bloating

• SIBO

• dysmotility

• systemic sclerosis

• severe reflux

Diet should therefore be individualized.

What About Butyrate Supplements?

Butyrate is one of the most interesting metabolites in barrier biology.

It may support:

• colonocyte function

• tight-junction integrity

• Treg regulation

• anti-inflammatory signaling

But oral butyrate supplementation has not been demonstrated to treat pulmonary fibrosis.

The evidence remains mechanistic and preclinical.

What About Glutamine?

Glutamine is often promoted for intestinal-barrier support.

It can serve as an energy substrate for intestinal epithelial cells and has been investigated in various gastrointestinal and critical illness settings.

But there is no evidence that glutamine supplementation modifies pulmonary fibrosis through intestinal-barrier repair.

It should not be marketed as an IPF treatment.

What About Fecal Microbiota Transplantation?

FMT can dramatically modify the intestinal microbial ecosystem.

Experimental studies have explored microbiota transfer in lung disease and pulmonary fibrosis models.

Some preclinical findings suggest that manipulating the gut microbiome can alter pulmonary inflammation and fibrosis.

However, FMT is not an established treatment for pulmonary fibrosis.

Its proven clinical applications are currently in very different gastrointestinal settings, particularly selected recurrent Clostridioides difficile infections.

Should Someone With Pulmonary Fibrosis Try to “Heal the Gut”?

The phrase can be misleading because it implies a universal protocol.

A more clinically useful question is:

Does this particular patient have a gastrointestinal problem that deserves evaluation and treatment?

Examples include:

• persistent bloating

• diarrhea

• constipation

• unexplained weight loss

• malabsorption

• reflux

• dysphagia

• suspected SIBO

• medication-related gastrointestinal symptoms

These problems should be evaluated on their own merits.

Treating them may improve:

• nutrition

• comfort

• food tolerance

• quality of life

But this should not be confused with proven reversal of lung fibrosis.

Nutrition May Matter More Than Restrictive “Gut Healing” Diets

Pulmonary fibrosis can be associated with:

• reduced appetite

• weight loss

• muscle loss

• frailty

• increased energy expenditure from breathing

A highly restrictive diet aimed at eliminating multiple foods may worsen these problems.

For many patients, the priorities include:

• adequate protein

• sufficient calories

• maintaining muscle mass

• appropriate dietary fiber when tolerated

• correction of documented deficiencies

• management of reflux or swallowing problems

The best gut strategy is not necessarily the most restrictive one.

GERD and Leaky Gut Are Different

Pulmonary fibrosis is commonly associated with gastroesophageal reflux.

The proposed pulmonary mechanism of reflux is mainly:

reflux
→ microaspiration
→ repeated exposure of the airway and alveoli

Leaky gut represents a different theoretical pathway:

intestinal barrier dysfunction
→ microbial products and metabolites
→ systemic circulation
→ pulmonary immune signaling

They may coexist.

But they should not be confused.

How Could the Gut Microbiome Influence Pulmonary Fibrosis Even Without Leaky Gut?

This is another important point.

The gut microbiome does not require a severely damaged intestinal barrier to influence the lungs.

Microbial metabolites can normally enter circulation and act on distant organs.

Examples include:

• SCFAs

• tryptophan metabolites

• bile-acid metabolites

These molecules can influence immune cells throughout the body.

Therefore, the gut–lung axis is broader than leaky gut.

Focusing exclusively on permeability may oversimplify the biology.

Five Major Ways the Microbiome May Influence Lung Fibrosis

Current research suggests that the microbiome may influence pulmonary fibrosis through several overlapping mechanisms.

1. Immune dysregulation

Changes in Tregs, Th17 cells, macrophages and inflammatory cytokines.

2. Barrier dysfunction

Altered intestinal and pulmonary epithelial integrity.

3. Microbial metabolites

Changes in SCFAs, tryptophan derivatives and bile acids.

4. Autophagy and cellular signaling

Microbial signals may influence PI3K/AKT/mTOR and related pathways.

5. Alveolar epithelial injury

Microbial products and peptides may contribute to epithelial injury and apoptosis.

A 2025 review identified these mechanisms as central components of the emerging microbiota–pulmonary fibrosis model. (Frontiers)

What We Know

Current evidence supports several conclusions.

We know that:

• pulmonary fibrosis is associated with altered microbial ecosystems

• a large 2026 human IPF study found associations between gut microbiota and disease severity

• experimental pulmonary fibrosis can be accompanied by intestinal-barrier dysfunction

• tight-junction proteins such as ZO-1 and occludin are altered in several animal models

• microbial products such as LPS can activate systemic immune pathways

• SCFAs and tryptophan metabolites can influence barrier and immune function

• gut-barrier dysfunction is biologically plausible as part of the lung–gut axis

(PubMed)

What We Do Not Know

We do not know:

• whether increased intestinal permeability occurs consistently in human IPF

• whether it appears before pulmonary fibrosis begins

• whether it predicts disease progression

• whether it independently influences FVC or DLCO

• whether repairing the gut barrier changes pulmonary outcomes

• whether commercial permeability tests identify meaningful IPF phenotypes

• whether probiotics, butyrate or other barrier-directed treatments modify survival

These are major gaps in the evidence.

What Does This Mean Clinically?

The practical interpretation should be cautious.

If a patient with pulmonary fibrosis has significant gastrointestinal symptoms, these should be evaluated and treated appropriately.

This may include assessment of:

• reflux

• swallowing dysfunction

• bowel symptoms

• nutritional status

• SIBO when clinically suspected

• malabsorption

• medication-related gastrointestinal effects

But a diagnosis of pulmonary fibrosis alone does not mean the patient has leaky gut.

And it does not automatically justify extensive permeability testing or supplement protocols.

Functional and Integrative Medicine Perspective

The gut–lung axis provides a useful framework for looking beyond the lung without abandoning established pulmonary medicine.

A comprehensive assessment may include:

• gastrointestinal symptoms

• diet

• nutritional adequacy

• metabolic health

• weight and muscle mass

• reflux and aspiration risk

• physical activity

• sleep

• environmental exposures

Where clinically indicated, specific gastrointestinal abnormalities can be evaluated.

The goal should be to improve the patient’s overall health and address relevant comorbidities.

It should not be to claim that pulmonary fibrosis can be reversed simply by “sealing the gut.”

What Treatment Still Matters Most?

Evidence-based pulmonary care remains central.

Depending on the type and severity of fibrosis, this may include:

• antifibrotic treatment

• immunomodulatory therapy for appropriate autoimmune ILD

• pulmonary rehabilitation

• oxygen therapy

• vaccination

• treatment of comorbidities

• smoking cessation

• lung transplantation evaluation when indicated

Gut-directed interventions should never delay appropriate specialist pulmonary treatment.

Where Is the Research Going?

Future research needs to move beyond simple stool bacterial profiles.

Ideally, studies should combine:

**gut metagenomics

• intestinal-permeability measurements

• microbial metabolomics

• immune profiling

• pulmonary function

• HRCT progression

• long-term outcomes**

Researchers need to determine whether intestinal-barrier dysfunction:

1. occurs before pulmonary fibrosis progresses

2. predicts clinically meaningful outcomes

3. can be modified

4. changes pulmonary outcomes when corrected

Without that sequence, leaky gut will remain an interesting mechanism rather than a validated therapeutic target.

Frequently Asked Questions

Can leaky gut cause pulmonary fibrosis?

There is currently no direct human evidence proving that increased intestinal permeability causes pulmonary fibrosis.

Animal and mechanistic studies support biological plausibility, but causality has not been established.

Is leaky gut common in IPF?

We do not currently know.

Gut microbiome abnormalities have been identified in IPF, but large human studies directly measuring intestinal permeability are lacking.

Is there evidence that the gut affects pulmonary fibrosis?

Yes.

Human studies show associations between gut microbial composition and IPF severity, while animal studies demonstrate microbiome, barrier and metabolic abnormalities during pulmonary fibrosis. (PubMed)

Does healing the gut reverse pulmonary fibrosis?

There is no clinical evidence that repairing intestinal permeability reverses established pulmonary fibrosis.

Can probiotics help pulmonary fibrosis?

Probiotics have shown interesting effects in experimental models, but no probiotic is currently proven to slow or reverse human IPF.

Can butyrate repair the gut and improve lung fibrosis?

Butyrate can support intestinal-barrier and immune function, but there is no adequate clinical evidence showing that butyrate supplementation improves pulmonary fibrosis.

Should patients with IPF test zonulin?

There is no validated role for commercial zonulin testing in determining the cause, severity or treatment of IPF.

Is leaky gut the same as dysbiosis?

No.

Dysbiosis refers to altered microbial ecology.

Leaky gut refers to increased intestinal permeability.

The two may be related but are not interchangeable.

Is leaky gut the same as SIBO?

No.

SIBO refers to abnormal microbial growth in the small intestine.

Intestinal permeability refers to barrier function.

They are distinct conditions.

Can diet support the intestinal barrier?

Diet can influence gut microbial composition and microbial metabolites.

A nutritionally adequate diet containing appropriate amounts of fiber may support gut health in many people, but no specific diet is proven to treat pulmonary fibrosis by repairing the intestinal barrier.

Key Takeaway

The most accurate interpretation of the evidence is:

Intestinal-barrier dysfunction is a plausible component of the gut–lung axis in pulmonary fibrosis and is supported by experimental studies, but direct evidence that “leaky gut” causes or drives human idiopathic pulmonary fibrosis remains limited.

Conclusion

The possibility that leaky gut and pulmonary fibrosis are connected is scientifically credible—but the evidence needs to be interpreted carefully.

Animal models of pulmonary fibrosis demonstrate:

• gut dysbiosis

• disruption of intestinal tight-junction proteins

• intestinal-barrier dysfunction

• altered microbial metabolites

• systemic immune abnormalities

These findings support a potential pathway in which intestinal-barrier dysfunction permits greater exposure to microbial products such as LPS, amplifying immune signals that may affect the lungs. (PubMed)

At the same time, microbial metabolites such as:

• butyrate

• other short-chain fatty acids

• tryptophan derivatives

• bile-acid metabolites

may influence both intestinal-barrier health and pulmonary immune signaling.

Human evidence also supports a gut–lung connection.

In 2026, analysis of 411 patients with idiopathic pulmonary fibrosis demonstrated associations between gut microbial composition, pulmonary disease severity and transplant-free survival. (PubMed)

But that study did not prove increased intestinal permeability.

This distinction is essential.

At present, we can reasonably say:

the gut microbiome is associated with pulmonary fibrosis.

We can also say:

intestinal-barrier dysfunction can accompany pulmonary fibrosis in experimental models.

What we cannot yet say is:

leaky gut causes IPF.

And we cannot say:

repairing leaky gut treats or reverses pulmonary fibrosis.

Future studies should directly measure intestinal permeability in well-characterized patients with IPF and other forms of ILD, integrate those findings with microbiome and metabolomic data, and determine whether barrier abnormalities predict pulmonary progression.

Only then will we know whether intestinal permeability is:

• a cause

• a consequence

• a disease modifier

• a biomarker

or some combination of these.

For now, gastrointestinal health remains an important component of comprehensive care—especially when patients experience reflux, bloating, altered bowel habits, malnutrition or other gastrointestinal symptoms.

But gut-directed care should complement, not replace, established treatment of pulmonary fibrosis.

The future of the gut–lung field may ultimately depend not on the broad concept of “leaky gut,” but on identifying specific barrier defects, microbial metabolites and immune pathways that can be measured, validated and therapeutically targeted.

That is where this emerging science may eventually become clinically meaningful.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical and academic interests include Integrative and Functional Pulmonology, the gut–lung axis, pulmonary fibrosis, autoimmune-associated interstitial lung disease, nutrition, metabolic health and emerging microbiome science.

Looking for a Comprehensive Approach to Pulmonary Fibrosis or ILD?

If you are living with pulmonary fibrosis or another form of interstitial lung disease and would like a comprehensive assessment that considers your pulmonary disease together with relevant gastrointestinal, nutritional, metabolic and lifestyle factors, you can explore the available online consultation options.

An integrative assessment may help identify clinically relevant gastrointestinal or nutritional issues while remaining firmly anchored to evidence-based pulmonary care.

Contact us through the consultation page or WhatsApp to learn more about online consultation options.

Functional and integrative care is intended to complement—not replace—appropriate pulmonary treatment, including antifibrotic or immunomodulatory therapy when indicated.

Medical Disclaimer: This article is for educational purposes only and does not constitute individualized medical advice. Patients with pulmonary fibrosis or interstitial lung disease should remain under appropriate specialist pulmonary care.

Related Topics

• Gut–Lung Axis and Pulmonary Fibrosis: Can Gut Health Affect Lung Fibrosis?

• Gut Dysbiosis and Pulmonary Fibrosis: What Does the Evidence Show?

• SCFAs and Pulmonary Fibrosis

• Butyrate and Lung Fibrosis

• Tryptophan Metabolism and Pulmonary Fibrosis

• Probiotics and Pulmonary Fibrosis

• Gut Microbiome and Interstitial Lung Disease

• SIBO and Systemic Sclerosis

• GERD, Microaspiration and Pulmonary Fibrosis

Gut Dysbiosis and Pulmonary Fibrosis: What Does the Evidence Show?

Pulmonary fibrosis is usually viewed as a disease centered within the lungs.

In idiopathic pulmonary fibrosis, repeated injury to alveolar epithelial cells, abnormal tissue repair, fibroblast activation and excessive deposition of extracellular matrix gradually replace normal lung architecture with scar tissue.

But researchers are increasingly asking whether factors outside the lungs may influence this process.

One of the most rapidly developing areas is the gut microbiome.

The human intestine contains trillions of microorganisms that interact continuously with the immune system, metabolism and intestinal barrier.

When this microbial ecosystem becomes disrupted—a state known as gut dysbiosis—the effects may extend far beyond the gastrointestinal tract.

This has led to growing interest in the gut–lung axis: the network of immune, metabolic and microbial signals connecting intestinal health with respiratory physiology.

Pulmonary fibrosis has now become part of this discussion.

Recent experimental studies have demonstrated changes in intestinal microbial composition, microbial metabolites and intestinal-barrier integrity during pulmonary fibrosis.

More importantly, human evidence is beginning to emerge.

In 2026, investigators analyzed the gut microbiota of 411 patients with idiopathic pulmonary fibrosis and found associations between microbial community characteristics, pulmonary disease severity and transplant-free survival.

That study represents an important step forward because it moves the gut–lung hypothesis beyond small exploratory cohorts.

However, the findings still do not prove that gut dysbiosis causes pulmonary fibrosis.

They also do not prove that correcting the microbiome can reverse or slow established fibrosis.

The current evidence therefore sits in an important middle ground:

the gut microbiome appears to be associated with pulmonary fibrosis biology, but microbiome-directed treatment remains investigational.

This article examines what the evidence actually shows.

What Is Gut Dysbiosis?

The intestinal microbiome consists of a complex ecosystem containing:

• bacteria

• viruses

• fungi

• archaea

• microbial genes

• microbial metabolites

These microorganisms participate in important physiological functions including:

• digestion

• vitamin synthesis

• bile-acid metabolism

• immune regulation

• maintenance of the intestinal barrier

• production of short-chain fatty acids

• metabolism of amino acids such as tryptophan

A healthy microbiome is not defined by one universal bacterial composition.

Different healthy people may have very different microbial profiles.

Gut dysbiosis therefore does not mean the presence of one specific “bad bacteria.”

Instead, it generally refers to disruption of the microbial ecosystem.

This may include:

• reduced microbial diversity

• depletion of potentially beneficial organisms

• expansion of pro-inflammatory or opportunistic organisms

• altered microbial metabolic function

• disturbed communication between microbes and the host immune system

Dysbiosis can be influenced by many factors, including:

• age

• diet

• antibiotics

• proton-pump inhibitors

• chronic illness

• infections

• metabolic disease

• intestinal motility

• geography

• smoking

• lifestyle

This is important in pulmonary fibrosis because many patients are older, have multiple comorbidities and use medications that themselves can affect gut microbial composition.

What Is the Gut–Lung Axis?

The gut–lung axis describes bidirectional communication between the gastrointestinal and respiratory systems.

The intestine does not need to physically connect with the lungs for this communication to occur.

Signals may travel through:

• systemic circulation

• microbial metabolites

• inflammatory cytokines

• immune-cell trafficking

• microbial products

A simplified model looks like this:

Diet and intestinal environment
↓
Gut microbiome
↓
Microbial metabolites and immune signals
↓
Systemic circulation
↓
Pulmonary immune cells and lung epithelium

The pathway is also bidirectional.

Severe lung disease can alter:

• physical activity

• diet

• medication use

• systemic inflammation

• gastrointestinal physiology

which may in turn modify the gut microbiome.

Therefore, the gut–lung axis should not be interpreted as a simple one-way pathway in which intestinal bacteria directly cause lung disease.

Is There Evidence of Gut Dysbiosis in Pulmonary Fibrosis?

Yes.

But the quality of the evidence varies considerably.

The strongest mechanistic evidence comes from animal models.

Human studies are newer and still relatively limited.

A major 2025 review integrating clinical and preclinical evidence identified altered microbial communities in several fibrotic lung conditions, including:

• idiopathic pulmonary fibrosis

• silicosis

• coal workers’ pneumoconiosis

The review identified five broad mechanisms through which microbial dysbiosis may influence pulmonary fibrosis:

1. immune dysregulation

2. gut–lung barrier dysfunction

3. sustained epithelial–mesenchymal signaling

4. altered autophagy

5. alveolar epithelial-cell injury or apoptosis

It also highlighted microbial mediators including:

• short-chain fatty acids

• tryptophan metabolites

• lipopolysaccharide

• bile-acid metabolites

The authors nevertheless emphasized that causality remains uncertain and that microbiome-directed therapy has not yet been standardized. (Frontiers⁠)

Human Evidence in Idiopathic Pulmonary Fibrosis

Human data are particularly important because experimental pulmonary fibrosis models do not fully replicate human IPF.

One small human study published in 2024 examined the intestinal microbiome in patients with idiopathic pulmonary fibrosis.

Researchers compared patients receiving antifibrotic therapy, patients not receiving antifibrotic treatment and healthy controls.

Differences in microbial composition were identified between the groups.

This provided early evidence that human IPF is associated with measurable intestinal microbial alterations.

But the study was small.

Small cohorts can generate useful hypotheses, but they cannot determine causality or reliably establish disease-specific microbial signatures.

The evidence became substantially stronger in 2026.

The 2026 CleanUP-IPF Gut Microbiome Study

In May 2026, researchers published one of the largest human analyses of the gut microbiome in idiopathic pulmonary fibrosis to date.

The study examined fecal samples from 411 participants with IPF enrolled in the CleanUP-IPF clinical trial.

Investigators used both:

• 16S rRNA sequencing

• shotgun metagenomic sequencing

They then assessed relationships between intestinal microbial characteristics and clinically important variables including:

• lung function

• disease severity

• medication exposure

• transplant-free survival

This study is particularly important because the sample size was far larger than previous gut microbiome studies in IPF. (PubMed⁠)

What Did the 411-Patient Study Show?

Several findings were clinically relevant.

The intestinal microbiome was influenced by factors such as:

• age

• sex

• proton-pump inhibitor use

This alone is important because it illustrates how strongly microbiome results can be affected by factors unrelated to the lung disease itself.

Researchers also found associations between microbial community composition and percent predicted DLCO.

DLCO reflects the lung’s ability to transfer gas and is an important physiological marker of disease severity in IPF.

Therefore, the association suggests that intestinal microbial patterns may relate to clinically meaningful pulmonary disease characteristics.

The study also identified associations between certain microbial taxa and transplant-free survival in selected treatment strata.

One unclassified genus within the Lachnospiraceae family was among the microbial features linked with survival-related outcomes.

This does not mean that Lachnospiraceae determine prognosis.

But it does suggest that the gut microbiome may contain biological information related to disease phenotype or severity.

Why This Study Matters

Until recently, much of the gut–pulmonary fibrosis discussion relied on:

• animal models

• small clinical cohorts

• mechanistic speculation

• extrapolation from other inflammatory diseases

The CleanUP-IPF analysis provides evidence from hundreds of patients with confirmed IPF.

This makes the association between the intestinal microbiome and pulmonary fibrosis harder to dismiss as a purely experimental concept.

At the same time, the study teaches another important lesson:

microbiome data are highly confounded.

Microbial composition can change with age, medications, geography, nutrition and disease severity.

Therefore, identifying a bacterium associated with IPF does not prove that the organism causes fibrosis.

Association Does Not Mean Causation

This principle is essential.

Imagine that patients with more severe IPF show lower abundance of a particular bacterial group.

Several explanations are possible.

The microbial change may contribute to disease.

Changes in metabolites or immune signaling could theoretically influence pulmonary biology.

Severe IPF may alter the microbiome.

Advanced disease can change:

• physical activity

• appetite

• diet

• medication exposure

• gastrointestinal physiology

which may secondarily change microbial ecology.

Another factor may influence both.

Age or proton-pump inhibitor use could affect both clinical outcomes and intestinal microbial composition.

The relationship may be bidirectional.

Lung disease may alter the intestinal environment, while gut-derived signals may also influence systemic immune and metabolic pathways.

This fourth model may ultimately prove the most realistic.

How Could Gut Dysbiosis Influence Pulmonary Fibrosis?

Current research suggests several potential mechanisms.

1. Immune Dysregulation

The intestinal microbiome is an important regulator of immune development and immune tolerance.

Gut microorganisms interact with:

• regulatory T cells

• Th17 cells

• dendritic cells

• macrophages

• B cells

• innate lymphoid cells

Pulmonary fibrosis is not simply an inflammatory disease.

Nevertheless, immune signaling influences:

• alveolar epithelial injury

• macrophage activation

• fibroblast behavior

• tissue remodeling

Dysbiosis could theoretically alter these pathways.

One potential mechanism involves the balance between:

T regulatory cells and Th17 cells.

Microbial metabolites can influence this balance.

Abnormal Treg/Th17 activity has been implicated in several autoimmune and fibrotic conditions.

Whether modifying these signals will alter human IPF remains unknown.

2. Intestinal Barrier Dysfunction

The intestinal epithelium normally creates a selective barrier separating intestinal microbes from systemic circulation.

Important tight-junction proteins include:

• ZO-1

• occludin

• claudins

Experimental pulmonary fibrosis models have demonstrated both gut microbial changes and disruption of intestinal barrier markers.

This raises the possibility that pulmonary fibrosis may be associated with increased intestinal permeability.

If the barrier becomes impaired, greater amounts of microbial material could enter systemic circulation.

This has sometimes been described as “leaky gut.”

However, the evidence needs careful interpretation.

Animal models provide biologically plausible evidence.

Direct human evidence proving that increased intestinal permeability drives idiopathic pulmonary fibrosis remains limited.

Therefore:

“Leaky gut causes pulmonary fibrosis” is not currently an evidence-based statement.

3. Lipopolysaccharide and Endotoxemia

One microbial molecule frequently discussed in gut–lung research is:

lipopolysaccharide, or LPS.

LPS is a component of the outer membrane of Gram-negative bacteria.

It can activate innate immune pathways through receptors such as:

TLR4

leading to downstream activation of pathways including:

NF-κB.

These pathways can increase inflammatory cytokine production.

TLR4-related signaling also interacts with processes involved in:

• epithelial injury

• fibroblast activation

• extracellular matrix production

A theoretical pathway therefore looks like this:

Gut dysbiosis
↓
Barrier dysfunction
↓
Increased microbial-product exposure
↓
LPS/TLR4 signaling
↓
Systemic inflammation and pulmonary signaling

This pathway has substantial mechanistic plausibility.

But its contribution to human IPF is still uncertain.

4. Short-Chain Fatty Acids

One of the most important ways gut bacteria communicate with the host is through short-chain fatty acids, or SCFAs.

The major SCFAs are:

• acetate

• propionate

• butyrate

They are produced when intestinal microbes ferment dietary substrates.

SCFAs can influence physiology through receptors including:

• GPR41

• GPR43

• GPR109A

They can also influence gene expression through effects on histone deacetylase activity.

SCFAs affect:

• regulatory T-cell function

• macrophage behavior

• intestinal barrier integrity

• epithelial biology

• inflammatory signaling

This makes them strong candidate mediators of the gut–lung axis.

Butyrate and Lung Fibrosis

Butyrate has received particular attention.

It is produced by several groups of anaerobic intestinal organisms, including members of:

• Roseburia

• Faecalibacterium

• Lachnospiraceae

Butyrate supports colonocyte metabolism and intestinal epithelial integrity.

It also has immune-regulatory and epigenetic effects.

Because of these properties, researchers have proposed that depletion of butyrate-producing bacteria could theoretically reduce protective immune or barrier signaling.

Experimental antifibrotic effects involving butyrate-related pathways have also been described.

However, three concepts should not be confused.

Low abundance of butyrate-associated bacteria

does not necessarily mean:

low intestinal butyrate production

and neither automatically means:

oral butyrate supplementation will treat pulmonary fibrosis.

No adequate human clinical trial has demonstrated that butyrate supplementation slows or reverses IPF.

5. Tryptophan Metabolism

Tryptophan provides another important connection between microbiome metabolism and host immunity.

Dietary tryptophan can enter several pathways:

• kynurenine metabolism

• serotonin metabolism

• microbial indole metabolism

Gut microorganisms can generate compounds such as:

• indole derivatives

• indole-3-acetic acid

• related microbial metabolites

Some interact with the aryl hydrocarbon receptor, or AhR.

AhR signaling can influence:

• epithelial integrity

• Treg/Th17 balance

• mucosal immunity

• inflammatory responses

Pulmonary fibrosis research has also investigated several tryptophan-related metabolites.

Some may promote profibrotic signaling.

Others may appear protective in experimental models.

Compounds such as:

• indole-3-acetic acid

• 5-methoxytryptophan

• selected AhR ligands

have shown effects on pathways involving:

• autophagy

• fibroblast activation

• epithelial senescence

• TGF-β signaling

These are scientifically interesting findings.

They are not established treatments for pulmonary fibrosis.

6. Bile-Acid Metabolites

The intestinal microbiome plays a central role in bile-acid metabolism.

Primary bile acids produced by the liver can be modified by intestinal microorganisms.

The resulting metabolites can signal through receptors such as:

• FXR

• TGR5

These pathways influence:

• immune activity

• metabolism

• epithelial function

• inflammatory signaling

Recent pulmonary fibrosis reviews include altered bile-acid metabolism among the possible mechanisms connecting intestinal dysbiosis with fibrotic lung disease. (Frontiers⁠)

The field remains early, but this supports a broader concept:

microbial function may matter more than individual bacterial names.

7. Autophagy

Autophagy is a cellular recycling process that removes damaged proteins and organelles.

It is essential for cellular homeostasis.

Impaired autophagy has been implicated in pulmonary fibrosis.

Microbial metabolites may influence signaling pathways such as:

PI3K → AKT → mTOR

which regulate autophagy.

Insufficient autophagy may:

• increase epithelial vulnerability to injury

• promote cellular senescence

• facilitate fibroblast activation

This provides another possible route through which microbiome-related metabolites could influence fibrosis.

Most evidence in this area remains preclinical.

8. Epithelial Injury and Fibroblast Activation

Repeated alveolar epithelial injury is central to current models of IPF.

Damaged epithelial cells release signals that promote:

• fibroblast recruitment

• myofibroblast differentiation

• collagen production

• extracellular matrix deposition

One of the major signaling pathways is:

TGF-β → Smad

Experimental microbiome-targeted interventions have altered this pathway in animal models.

Recent experimental work with probiotic organisms has also reported reduced bleomycin-induced fibrosis together with changes in intestinal microbial composition and TGF-β-related signaling.

This supports mechanistic plausibility.

But once again:

a probiotic reducing fibrosis in mice is not evidence that probiotics treat IPF in humans.

9. Microbial Peptides and Direct Lung Injury

Another emerging mechanism involves microbial peptides.

The 2025 pulmonary fibrosis gut–lung review identifies corisin, a bacterial peptide, as one potential mediator capable of promoting alveolar epithelial-cell apoptosis in experimental fibrosis pathways. (Frontiers⁠)

This is important because it expands the gut–lung discussion beyond classical metabolites.

Microbes may potentially influence lung biology through:

• metabolites

• structural products

• peptides

• immune signaling

This area requires substantially more research.

What Do Animal Models Tell Us?

Animal models provide some of the strongest mechanistic evidence supporting the gut–lung axis in pulmonary fibrosis.

Bleomycin and silica models have demonstrated:

• intestinal dysbiosis

• altered microbial metabolites

• intestinal barrier abnormalities

• changes in immune signaling

• correlations between microbial profiles and fibrosis severity

Experimental manipulation of the microbiome has also altered fibrosis outcomes.

Strategies investigated include:

• probiotics

• prebiotics

• high-fiber diets

• microbial metabolites

• fecal microbiota transplantation

• antibiotics

• experimental herbal formulations

The 2025 review concluded that several microbiome-targeted interventions have shown antifibrotic activity in experimental models. (Frontiers⁠)

But there is a major translational limitation.

Bleomycin-induced fibrosis is not identical to human IPF.

Animal models often contain a stronger inflammatory phase and may partially resolve spontaneously.

Human IPF is a chronic, age-associated and highly heterogeneous fibrotic disease.

Therefore, experimental success cannot be assumed to translate into human treatment efficacy.

What About the Lung Microbiome?

The intestinal microbiome is only one part of the microbial story.

The lower respiratory tract also contains microbial communities.

Research in IPF has identified:

• altered lung microbial composition

• increased bacterial burden in some cohorts

• reduced diversity

• associations between pulmonary bacterial burden and disease outcomes

This raises the possibility that several microbial ecosystems interact in pulmonary fibrosis.

A broader model may involve:

oral microbiome
↕
lung microbiome
↕
pulmonary immunity
↕
systemic circulation
↕
gut microbiome

The gut and lung microbiomes should therefore not be treated as interchangeable.

Could Oral Health Matter?

Potentially.

The lungs are continually exposed to microorganisms originating from the upper airway.

Microaspiration of oral secretions occurs even in healthy people.

Oral microbial communities may therefore influence the lower-airway microbiome.

Poor oral health, periodontal disease, aspiration risk and altered swallowing may all theoretically affect respiratory microbial ecology.

However, oral-health interventions have not been proven to modify the progression of IPF.

This remains another emerging area of investigation.

Gut Dysbiosis in Other Fibrotic Lung Diseases

The gut–lung hypothesis extends beyond idiopathic pulmonary fibrosis.

Microbial alterations have also been reported in conditions including:

• silicosis

• coal workers’ pneumoconiosis

• systemic sclerosis-associated ILD

• rheumatoid arthritis-associated ILD

• myositis-associated ILD

This suggests that gut–immune interactions may influence fibrosis across multiple disease categories.

However, the underlying mechanisms of these diseases differ.

It would therefore be inappropriate to assume that one microbial pattern or treatment applies to all forms of pulmonary fibrosis.

Autoimmune ILD May Be Especially Relevant

Autoimmune-associated ILD may be particularly interesting from a microbiome perspective because the microbiome is already known to influence systemic immune regulation.

Recent human studies have identified microbiome differences in:

• systemic sclerosis-associated ILD

• rheumatoid arthritis-associated ILD

• myositis-associated ILD

For example, a multinational systemic sclerosis study involving 285 patients demonstrated a distinct gut microbial signature in SSc-ILD and relationships between microbial pathways and radiological ILD extent.

These studies strengthen the concept of a broader:

gut–immune–lung axis

rather than a purely gastrointestinal explanation for disease.

Is Gut Dysbiosis the Same as SIBO?

No.

This distinction is clinically important.

Gut dysbiosis refers broadly to disruption of microbial ecology.

SIBO refers specifically to abnormal microbial overgrowth or composition within the small intestine.

A person can have dysbiosis without SIBO.

A stool microbiome test also does not diagnose SIBO.

Breath testing is typically used clinically when SIBO is suspected.

SIBO may be particularly common in systemic sclerosis because of intestinal dysmotility, but it is not currently established as a cause of idiopathic pulmonary fibrosis.

Is Dysbiosis the Same as “Leaky Gut”?

No.

These concepts overlap but are not synonymous.

Dysbiosis refers to altered microbial ecology.

Increased intestinal permeability refers to altered intestinal-barrier function.

One may contribute to the other.

But a person may have one without clear evidence of the other.

Both have been investigated experimentally in pulmonary fibrosis.

Neither has yet been established as a routine clinical biomarker for IPF.

Can Gut Dysbiosis Cause Pulmonary Fibrosis?

At present:

we do not know.

The evidence increasingly supports an association.

Animal models support mechanistic plausibility.

Human observational studies are becoming stronger.

But human causality has not been demonstrated.

To establish causality, researchers would ideally need to show that:

1. dysbiosis develops before fibrosis

2. specific microbial changes predict disease progression

3. correcting those abnormalities changes clinically meaningful lung outcomes

That evidence does not yet exist.

Can Treating Gut Dysbiosis Treat Pulmonary Fibrosis?

There is currently no microbiome-directed therapy proven to treat IPF.

This includes:

• probiotics

• prebiotics

• synbiotics

• butyrate supplements

• FMT

• commercial microbiome protocols

• elimination diets

No adequately powered human trial has demonstrated that these interventions reliably:

• improve FVC

• improve DLCO

• reverse HRCT fibrosis

• prevent progressive pulmonary fibrosis

• reduce mortality

This is one of the most important clinical points for patients to understand.

Probiotics and Pulmonary Fibrosis

Probiotics have generated substantial research interest.

Selected probiotic strains can influence:

• gut microbial composition

• immune signaling

• barrier function

• microbial metabolite production

Animal pulmonary fibrosis studies have demonstrated antifibrotic effects with certain specific strains.

However, probiotic effects are highly strain-specific.

The effect of one strain cannot automatically be generalized to another.

More importantly, no probiotic strain has been established as a disease-modifying treatment for human IPF.

Prebiotics, Fiber and the Microbiome

Prebiotics provide substrates that can support selected microbial populations.

Dietary fiber can increase microbial fermentation and influence SCFA production.

This is biologically attractive.

But the clinical interpretation requires caution.

There is no evidence that a high-fiber diet reverses pulmonary fibrosis.

And some patients with fibrotic lung disease may also have:

• bloating

• SIBO

• intestinal dysmotility

• severe reflux

• systemic sclerosis

• reduced appetite

• malnutrition

Therefore, dietary recommendations should be individualized.

What About Butyrate Supplements?

Butyrate has promising mechanistic properties.

But mechanistic plausibility is not the same as clinical efficacy.

At present, butyrate supplementation has not been demonstrated to:

• improve FVC

• slow IPF progression

• reverse fibrosis

• improve survival

Therefore, butyrate should be regarded as an experimental research target rather than an established IPF therapy.

What About Fecal Microbiota Transplantation?

FMT can substantially alter gut microbial composition.

Its strongest established clinical role is in selected patients with recurrent Clostridioides difficile infection.

Animal studies have investigated FMT in pulmonary fibrosis and other lung conditions.

Some have shown reductions in inflammation or fibrosis.

However, FMT has not been established as treatment for human pulmonary fibrosis.

It should not currently be used for IPF outside an appropriate research context.

What About Antibiotics?

Antibiotics are particularly interesting because early lung microbiome research raised the possibility that altering microbial burden might influence IPF outcomes.

The CleanUP-IPF trial itself examined antimicrobial treatment.

However, broad antimicrobial therapy has not become an established disease-modifying strategy for IPF.

This illustrates an important principle:

changing microbial abundance is not necessarily the same as correcting microbial function.

Future treatment may require more precise approaches.

Could Diet Modify the Gut–Lung Axis?

Yes, diet can modify the microbiome.

It influences:

• microbial diversity

• substrate availability

• SCFA production

• bile-acid metabolism

• host metabolic health

But no specific “pulmonary fibrosis microbiome diet” has been clinically validated.

A useful nutritional strategy should instead focus on:

• adequate protein

• preservation of muscle

• appropriate calories

• diverse nutrient intake

• metabolic health

• gastrointestinal tolerance

The objective should not simply be “feeding good bacteria.”

Nutrition and Muscle Mass Matter in ILD

Patients with interstitial lung disease can develop:

• weight loss

• reduced appetite

• sarcopenia

• reduced exercise tolerance

• frailty

These factors may influence clinical outcomes independently of microbiome biology.

Therefore, any gut-directed intervention that causes unnecessary dietary restriction may actually be harmful.

Maintaining muscle mass and nutritional adequacy should remain a priority.

What About GERD and Microaspiration?

Gastroesophageal reflux is common in IPF.

The potential pulmonary mechanism differs from the gut–lung microbiome pathway.

Reflux may theoretically affect the lungs through:

reflux
→ microaspiration
→ repeated epithelial exposure

The gut–lung axis instead involves:

gut microbes
→ metabolites and immune signaling
→ systemic circulation
→ lung

These pathways may coexist.

But they should not be treated as the same mechanism.

Current IPF guidelines do not recommend antacid therapy solely to improve respiratory outcomes.

Symptomatic GERD should still be treated according to standard clinical indications.

Can Improving Gut Health Still Benefit Someone With Pulmonary Fibrosis?

Potentially, yes.

But the goals need to be realistic.

A patient with pulmonary fibrosis may also have:

• reflux

• constipation

• diarrhea

• persistent bloating

• nutritional deficiencies

• weight loss

• SIBO

• medication-related GI symptoms

Appropriate assessment and treatment of these conditions may improve:

• quality of life

• food tolerance

• nutritional intake

• bowel function

• symptom burden

Those benefits matter even if lung fibrosis itself does not change.

Should Patients With Pulmonary Fibrosis Have Commercial Microbiome Testing?

Not routinely for the purpose of managing pulmonary fibrosis.

Commercial stool testing currently cannot determine:

• whether dysbiosis caused IPF

• whether fibrosis will progress

• whether antifibrotic treatment is required

• whether a specific organism is causing lung fibrosis

• which probiotic will improve FVC

Research metagenomics and commercial stool analysis are not equivalent.

Pulmonary fibrosis treatment decisions should remain based on established clinical assessment.

What Tests Actually Matter in Pulmonary Fibrosis?

Depending on the type of ILD, clinically relevant evaluation may include:

• high-resolution CT

• pulmonary function testing

• DLCO

• autoimmune serology

• exposure assessment

• oxygenation

• multidisciplinary ILD review

• echocardiography or pulmonary hypertension assessment when appropriate

• lung transplantation evaluation in advanced disease

Microbiome testing currently does not replace any of these.

Functional and Integrative Medicine Perspective

The growing gut–lung evidence provides an opportunity for a more comprehensive approach to pulmonary fibrosis.

It does not justify replacing established pulmonary medicine.

A clinically responsible integrative assessment can consider:

• gastrointestinal symptoms

• reflux

• bowel function

• nutritional status

• muscle mass

• metabolic health

• physical activity

• sleep

• environmental exposures

• medication effects

Where appropriate, specific gastrointestinal problems such as SIBO or malabsorption may also be evaluated.

The key is to distinguish:

clinically useful supportive care

from:

unproven claims that treating the microbiome reverses fibrosis.

What We Know

Current evidence supports the following conclusions:

• the gut and lung communicate through immune and metabolic pathways

• intestinal dysbiosis occurs in experimental pulmonary fibrosis

• human IPF is associated with measurable gut microbial differences

• a 2026 study involving 411 patients identified associations between gut microbiota and pulmonary disease severity

• microbial characteristics were associated with DLCO

• selected microbial features were associated with transplant-free survival

• SCFAs, tryptophan metabolites, LPS and bile-acid metabolites are plausible biological mediators

• experimental manipulation of the microbiome can modify fibrosis in animal models

The gut microbiome is therefore a credible pulmonary fibrosis research target. (PubMed⁠)

What We Do Not Know

Important uncertainties remain.

We do not yet know:

• whether gut dysbiosis causes IPF

• whether microbial changes occur before disease begins

• whether dysbiosis predicts progression independently of other risk factors

• whether correcting dysbiosis slows FVC decline

• whether probiotics improve pulmonary outcomes

• whether butyrate supplementation helps IPF

• whether FMT is beneficial

• whether commercial stool testing can guide pulmonary treatment

• which microbial pathways are causal rather than simply associated with disease

These are major unanswered questions.

What Does This Mean for Patients?

The practical message should be balanced.

Gut health matters.

But gut treatment is not a replacement for pulmonary fibrosis treatment.

If a patient with IPF or another fibrotic ILD has gastrointestinal symptoms, those symptoms deserve appropriate evaluation.

Attention to:

• nutrition

• reflux

• bowel function

• weight

• muscle mass

• metabolic health

can be part of comprehensive care.

At the same time, established pulmonary management remains central.

Depending on diagnosis and disease stage, this may include:

• antifibrotic treatment

• immunomodulatory therapy for autoimmune ILD

• pulmonary rehabilitation

• oxygen therapy

• vaccination

• management of comorbidities

• transplant evaluation

Where Is Gut–Lung Research Going Next?

The field is moving beyond simply asking:

Which bacteria are increased or decreased?

Future research will probably integrate:

**metagenomics

• metabolomics

• immune profiling

• pulmonary function

• HRCT progression

• longitudinal outcomes**

This may help researchers identify:

• microbial pathways associated with progression

• metabolites that influence fibrotic biology

• patient subgroups with different microbial phenotypes

• biomarkers that predict outcome

• therapeutic targets

Future strategies could potentially include:

• precision probiotics

• defined microbial consortia

• targeted prebiotics

• postbiotics

• microbial metabolites

• engineered organisms

• individualized nutrition

But these interventions need rigorous clinical testing.

What Would a Successful Microbiome Trial Need to Show?

A meaningful pulmonary fibrosis microbiome trial should not simply report that the stool microbiome changed.

It should demonstrate improvement in clinically relevant outcomes such as:

• FVC decline

• DLCO

• HRCT progression

• exercise capacity

• quality of life

• hospitalization

• transplant-free survival

Only then could microbiome modification begin to be considered a genuine pulmonary therapeutic strategy.

Frequently Asked Questions

Can gut dysbiosis cause pulmonary fibrosis?

It has not been proven.

Gut dysbiosis is associated with pulmonary fibrosis in experimental studies and emerging human research, but causality in humans remains uncertain.

Is the gut microbiome different in people with IPF?

Yes.

Several studies have reported differences in intestinal microbial composition in IPF.

The strongest recent human evidence comes from a 2026 study of 411 patients showing associations between gut microbiota, DLCO and transplant-free survival. (PubMed⁠)

Can probiotics reverse pulmonary fibrosis?

No.

No probiotic has been proven to reverse or stop human pulmonary fibrosis.

Animal studies are promising but are not sufficient to establish treatment efficacy.

Does butyrate help pulmonary fibrosis?

Butyrate has biologically interesting immune and epigenetic effects and has been studied experimentally.

However, butyrate supplementation has not been shown in clinical trials to treat IPF.

Is leaky gut linked to pulmonary fibrosis?

Animal pulmonary fibrosis models demonstrate intestinal-barrier abnormalities.

Direct human evidence proving that increased intestinal permeability drives IPF is still limited.

Is SIBO associated with pulmonary fibrosis?

SIBO may occur in patients with conditions such as systemic sclerosis because of intestinal dysmotility.

It has not been established as a cause of idiopathic pulmonary fibrosis.

Should I have a stool microbiome test if I have pulmonary fibrosis?

Not routinely for the purpose of managing the lung disease.

Commercial microbiome testing cannot currently predict IPF progression or determine antifibrotic therapy.

Can diet improve the gut microbiome in pulmonary fibrosis?

Diet can certainly influence intestinal microbial composition.

However, there is no specific microbiome diet proven to reverse pulmonary fibrosis.

Nutrition should focus on adequacy, muscle preservation and individual gastrointestinal tolerance.

Is the lung microbiome different from the gut microbiome?

Yes.

They are distinct microbial ecosystems.

Both are being investigated in pulmonary fibrosis and may communicate through immune and metabolic pathways.

Could future microbiome treatments help pulmonary fibrosis?

Possibly.

The field is investigating microbial metabolites, probiotics, prebiotics, FMT and other targeted strategies.

At present, these remain experimental for pulmonary fibrosis.

Key Takeaway

The evidence can be summarized in one sentence:

Gut dysbiosis is increasingly associated with pulmonary fibrosis, and several biologically plausible gut–lung mechanisms have been identified, but we do not yet know whether dysbiosis causes human IPF or whether modifying the microbiome can improve pulmonary outcomes.

That distinction is essential.

Conclusion

The relationship between gut dysbiosis and pulmonary fibrosis has moved from a speculative concept into a legitimate area of pulmonary research.

Preclinical studies demonstrate that pulmonary fibrosis can be accompanied by changes in:

• intestinal microbial composition

• microbial metabolites

• intestinal barrier integrity

• immune signaling

Mechanistic research suggests that the gut microbiome may influence pulmonary biology through pathways involving:

• short-chain fatty acids

• tryptophan metabolism

• lipopolysaccharide

• bile acids

• immune regulation

• autophagy

• epithelial injury

• fibroblast activation

Human evidence is also becoming stronger.

Most importantly, the 2026 CleanUP-IPF microbiome analysis involving 411 patients with idiopathic pulmonary fibrosis demonstrated associations between intestinal microbial characteristics, pulmonary disease severity and transplant-free survival. (PubMed⁠)

That does not prove causation.

But it does provide clinically meaningful evidence that the intestinal microbiome is connected with the biological phenotype of IPF.

The critical question now is no longer simply:

“Is the gut microbiome different in pulmonary fibrosis?”

Increasing evidence suggests that it is.

The more important questions are:

Do those microbial changes contribute to disease progression?

Which microbial metabolites actually influence fibrotic pathways?

Can changing the microbiome improve meaningful pulmonary outcomes?

Until those questions are answered, microbiome-directed therapy should remain investigational.

For patients, gastrointestinal symptoms, nutrition, reflux, metabolic health and muscle preservation can still be appropriately addressed as part of comprehensive care.

But these strategies should complement—not replace—evidence-based pulmonary treatment.

The future of the field may ultimately lie not in a generic concept of “healing the gut,” but in identifying specific microbial functions, metabolites and host–microbe interactions that influence fibrotic disease.

That is where gut–lung science may eventually become clinically actionable.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical and academic interests include Integrative and Functional Pulmonology, the gut–lung axis, pulmonary fibrosis, autoimmune-associated interstitial lung disease, nutrition, metabolic health and emerging microbiome science.

Looking for a Comprehensive Approach to Pulmonary Fibrosis or ILD?

If you are living with pulmonary fibrosis or another form of interstitial lung disease and would like a comprehensive assessment that considers your pulmonary disease together with relevant gastrointestinal, nutritional, metabolic and lifestyle factors, you can explore the available online consultation options.

The purpose of an integrative assessment is not to replace established pulmonary treatment, but to identify additional areas of health that may be relevant to symptoms, resilience and overall well-being.

Contact us through the consultation page or WhatsApp to learn more about online consultation options.

Functional and integrative care is intended to complement—not replace—appropriate pulmonary treatment, including antifibrotic or immunomodulatory therapy when indicated.

Medical Disclaimer: This article is provided for educational purposes only and does not constitute individualized medical advice. Patients with pulmonary fibrosis or interstitial lung disease should remain under appropriate specialist pulmonary care.

Related Topics:

• Gut–Lung Axis and Pulmonary Fibrosis: Can Gut Health Affect Lung Fibrosis?

• Leaky Gut and Pulmonary Fibrosis: Is There Scientific Evidence?

• SCFAs and Pulmonary Fibrosis

• Butyrate and Lung Fibrosis

• Tryptophan Metabolism and Pulmonary Fibrosis

• Probiotics and Pulmonary Fibrosis

• Gut Microbiome and Interstitial Lung Disease

• Gut Microbiome and Systemic Sclerosis–Associated ILD

• GERD, Microaspiration and Pulmonary Fibrosis

References

1. Kim JS, Loe A, Ma SF, et al. Gut microbiota associate with disease severity and survival in idiopathic pulmonary fibrosis. Am J Respir Crit Care Med. Published online May 19, 2026. doi:10.1093/ajrccm/aamag249.

2. Yang J, Wang J, Li J, Yang S. Lung-gut axis, intestinal microbiota, and pulmonary fibrosis: mechanisms and therapeutic potential. Front Microbiol. 2025;16:1711299. doi:10.3389/fmicb.2025.1711299.

3. Gut microbiota profiles of patients with idiopathic pulmonary fibrosis. Experimental Lung Research. 2024.

Antisynthetase Syndrome, the Microbiome and Interstitial Lung Disease: Is There a Gut–Lung Connection?

Could the Microbiome Influence Lung Disease in Antisynthetase Syndrome?

Antisynthetase syndrome is a systemic autoimmune disease defined by autoantibodies against aminoacyl-transfer RNA synthetases.

The syndrome can involve:

• interstitial lung disease

• inflammatory myopathy

• inflammatory arthritis

• Raynaud phenomenon

• mechanic’s hands

• fever

Among these manifestations, interstitial lung disease is one of the most clinically important and is a major determinant of morbidity and mortality. Recent longitudinal research continues to identify ILD as the principal driver of outcome in antisynthetase syndrome. (PubMed⁠)

The pulmonary phenotype is also heterogeneous.

Some patients develop relatively indolent chronic ILD.

Others develop progressive or severe disease.

This variability raises an important biological question:

Why do patients carrying different antisynthetase antibodies develop different patterns and trajectories of lung disease?

Genetics, autoantibody phenotype and immune pathways clearly matter.

But emerging microbiome research suggests that mucosal microbial communities may also interact with pulmonary immunity.

Importantly, however, the evidence in antisynthetase syndrome differs from the evidence in systemic sclerosis.

In systemic sclerosis-associated ILD, there is now substantial human research directly examining the gut microbiome.

In antisynthetase syndrome, the most disease-specific microbiome evidence currently relates to the lung microbiome, not the intestinal microbiome.

That distinction needs to remain clear.

What Is Antisynthetase Syndrome?

Antisynthetase syndrome is characterized by antibodies targeting enzymes responsible for attaching amino acids to transfer RNA.

The most familiar antibody is:

anti-Jo-1, directed against histidyl-tRNA synthetase.

Other antisynthetase antibodies include:

• anti-PL-7

• anti-PL-12

• anti-EJ

• anti-OJ

• anti-KS

• anti-Zo

• anti-Ha

The clinical phenotype differs considerably between antibody subgroups.

This is particularly relevant to the lungs.

For example, non-Jo-1 antibodies such as anti-PL-7 and anti-PL-12 have often been associated with a stronger pulmonary phenotype and may present with ILD even when muscle disease is subtle. Reviews of myositis-associated ILD have reported that ILD may be more frequent and severe in PL-7/PL-12 disease than in anti-Jo-1-positive disease. (PubMed⁠)

Therefore, antisynthetase syndrome should not be considered a single uniform pulmonary disorder.

Why Is ILD So Important in Antisynthetase Syndrome?

ILD may appear:

• before myositis

• simultaneously with other manifestations

• after the diagnosis of autoimmune disease

Some patients have little or no obvious muscle weakness.

This means the lung may be the organ that brings the patient to medical attention.

Common imaging patterns include:

• NSIP

• organizing pneumonia

• mixed NSIP/OP

• UIP in selected cases

The disease course can range from improvement with immunosuppression to recurrent or progressive ILD.

A 2026 longitudinal study specifically emphasizes that different trajectories of antisynthetase-associated ILD exist and that factors determining those trajectories remain incompletely understood. (PubMed⁠)

This uncertainty creates interest in additional biological modifiers—including microbial exposures.

Why Might the Microbiome Matter in an Autoimmune Lung Disease?

The immune system develops and functions in constant interaction with microorganisms.

Mucosal surfaces such as the:

• intestine

• oral cavity

• upper respiratory tract

• lower respiratory tract

are major sites of immune–microbial communication.

Microorganisms can influence immunity through:

• microbial antigens

• pattern-recognition receptors

• microbial metabolites

• epithelial-barrier signaling

• T-cell differentiation

• macrophage behavior

This creates a plausible model in which microbial communities might modify autoimmune disease activity.

But there is an important conceptual issue.

A microbiome association could mean that microbes contribute to disease.

Or disease could alter the microbiome.

Or treatment could alter both.

Therefore, microbiome studies should be viewed as the beginning of a mechanistic investigation—not automatic evidence of causation.

What Evidence Exists Specifically in Antisynthetase Syndrome?

The most direct disease-specific evidence comes from a study investigating the lung microbiome in antisynthetase syndrome-associated ILD.

Researchers analyzed bronchoalveolar lavage fluid from patients with antisynthetase syndrome and compared microbial profiles according to anti-Jo-1 status.

The study included:

• 6 anti-Jo-1-positive patients

• 17 non-Jo-1-positive patients

using 16S rRNA sequencing of BAL fluid. (PubMed⁠)

This is a very small study.

Nevertheless, it provides direct evidence that the pulmonary microbial environment may differ between antisynthetase phenotypes.

What Did the Lung Microbiome Study Find?

One of the major findings involved the genus:

Veillonella.

Veillonella abundance was significantly lower in the anti-Jo-1-positive group than in patients without anti-Jo-1 antibodies.

The investigators also identified associations between Veillonella and inflammatory cells in bronchoalveolar lavage.

Within the anti-Jo-1 group, Veillonella abundance showed:

• a strong negative correlation with macrophages

• positive correlations with eosinophils

• positive correlations with lymphocytes

• a strong positive relationship with Prevotella abundance

The investigators concluded that the lung microbiome differed according to antisynthetase phenotype and might interact with the inflammatory cellular environment. (PubMed⁠)

What Is Veillonella?

Veillonella is a genus commonly found in:

• the oral cavity

• upper respiratory tract

• gastrointestinal tract

Its presence in the lower airway is often interpreted within the broader context of microaspiration and migration of oral microorganisms into the lung.

However, Veillonella should not simply be labeled as either “good” or “bad.”

Its biological significance depends on:

• microbial community

• host immune status

• airway environment

• disease phenotype

The antisynthetase study therefore does not prove that lower Veillonella causes anti-Jo-1 lung disease.

It shows that microbial ecology and pulmonary immune phenotype may be linked.

Why Is Prevotella Interesting?

Prevotella is another common mucosal genus found in the oral and gastrointestinal microbiota.

It has attracted substantial attention in autoimmune diseases, including rheumatoid arthritis.

In the antisynthetase study, Veillonella correlated strongly with Prevotella.

This could reflect shared ecological conditions within the airway.

Again, this does not establish that either organism causes ILD.

But it suggests the lower respiratory microbiome may behave as an ecosystem rather than a collection of unrelated bacteria.

The Lung Microbiome Is Not the Same as the Gut Microbiome

This distinction is essential.

A BAL study tells us about microorganisms present in the pulmonary environment.

It does not tell us directly what is happening in the intestinal microbiome.

The microbiome should therefore be considered across several connected compartments:

oral microbiome
↓
airway microbiome

and potentially:

gut microbiome
↓
systemic immune/metabolic signaling
↓
lung

These are related concepts but not identical mechanisms.

What About the Gut Microbiome in Antisynthetase Syndrome?

This is where evidence becomes much thinner.

At present, robust human studies specifically characterizing the gut microbiome in well-defined antisynthetase syndrome cohorts are lacking.

Some relevant clues come from broader inflammatory myopathy research.

A 2023 metagenomic study in patients with idiopathic inflammatory myopathies found intestinal dysbiosis and demonstrated additional microbial differences between rapidly progressive ILD and chronic ILD.

That cohort included patients with myositis-related autoantibodies, including antisynthetase antibodies, but it was not designed as a dedicated antisynthetase gut-microbiome study.

Therefore, it provides supportive context—not definitive antisynthetase-specific evidence.

Why Is This Evidence Gap Important?

It prevents us from making claims such as:

“Patients with antisynthetase syndrome have a specific gut microbiome pattern.”

That has not yet been demonstrated convincingly.

Likewise, there is no established gut microbial signature specific to:

• anti-Jo-1

• anti-PL-7

• anti-PL-12

• anti-EJ

• anti-OJ

Much more research is required.

Could Different Autoantibodies Be Associated With Different Microbiomes?

This is an intriguing possibility.

The pulmonary phenotype differs between antisynthetase antibodies.

If microbial ecology interacts with the immune system, different autoantibody phenotypes might theoretically show different microbial patterns.

The anti-Jo-1 lung microbiome study provides a preliminary signal supporting this concept because anti-Jo-1-positive and non-Jo-1 patients had different airway microbial characteristics. (PubMed⁠)

Future studies should therefore stratify patients by antibody rather than combining all antisynthetase syndrome patients into one group.

How Could Microbes Influence Antisynthetase ILD?

Several mechanisms are biologically plausible.

1. Mucosal Immune Activation

Antisynthetase syndrome is an autoimmune disease.

Mucosal surfaces are major sites of immune activation.

Repeated microbial exposure could influence:

• innate immune signaling

• antigen presentation

• T-cell differentiation

• cytokine production

In genetically and immunologically susceptible individuals, chronic mucosal activation might contribute to systemic autoimmunity.

This remains a hypothesis.

2. Pattern-Recognition Receptors

Microbial molecules interact with receptors such as:

• Toll-like receptors

• NOD-like receptors

These receptors detect microbial structures and activate inflammatory pathways.

For example:

TLR signaling → NF-κB activation → inflammatory cytokines

These pathways can influence pulmonary macrophages and epithelial cells.

Persistent inappropriate activation might theoretically contribute to autoimmune lung injury.

3. Macrophage–Microbiome Interaction

The antisynthetase lung microbiome study found a strong relationship between Veillonella abundance and macrophage proportions.

Macrophages are particularly important in ILD because they can participate in:

• innate immune responses

• tissue repair

• fibroblast signaling

• extracellular-matrix remodeling

Different microbial environments could theoretically alter macrophage phenotype.

Whether this contributes to disease severity remains unknown. (PubMed⁠)

4. Epithelial Injury

Repeated epithelial injury is a major component of many ILDs.

Microbial products can interact directly with respiratory epithelial cells.

Depending on the context, these signals could influence:

• epithelial inflammation

• barrier integrity

• cytokine production

• repair responses

In autoimmune ILD, these processes may interact with systemic immune activity.

5. Oral–Lung Microbial Migration

The lungs are continuously exposed to small amounts of material originating from the upper airway.

Microaspiration occurs even in healthy people.

The lower-airway microbiome is therefore partly shaped by:

• immigration of oral microorganisms

• elimination through cough and mucociliary clearance

• local growth conditions

Veillonella and Prevotella are both organisms frequently associated with oral microbial communities.

Their presence in BAL fluid may therefore reflect oral–lung microbial trafficking.

Could Reflux and Microaspiration Be Relevant?

Potentially.

Microaspiration can influence the lower-airway microbial environment.

Patients with chronic autoimmune disease may also experience:

• reflux

• esophageal dysfunction

• medication-related gastrointestinal symptoms

However, reflux has not been established as a primary driver of antisynthetase syndrome ILD.

The concept should therefore remain separate from the immune microbiome hypothesis.

6. Gut-Derived Microbial Metabolites

Even without gut bacteria reaching the lungs, microbial metabolites may enter circulation.

These include:

• SCFAs

• tryptophan metabolites

• bile-acid metabolites

• microbial peptides

These molecules can affect immune-cell behavior at distant sites.

This provides the major theoretical mechanism for a gut–lung axis in antisynthetase syndrome.

But direct evidence remains limited.

Short-Chain Fatty Acids

SCFAs such as:

• butyrate

• propionate

• acetate

can influence:

• regulatory T cells

• macrophages

• intestinal-barrier function

• inflammatory signaling

This makes them plausible mediators in autoimmune disease.

However, no clinical study has demonstrated that manipulating SCFAs modifies antisynthetase ILD.

Tryptophan Metabolism

Microbial metabolism of tryptophan can generate indole derivatives that influence the aryl hydrocarbon receptor, or AhR.

AhR signaling participates in:

• mucosal immunity

• Treg/Th17 balance

• epithelial-barrier regulation

These pathways are relevant to systemic autoimmunity.

But they have not yet been specifically validated as therapeutic targets in antisynthetase syndrome.

Molecular Mimicry

Another theoretical mechanism is molecular mimicry.

Microbial proteins can sometimes resemble host proteins.

This may contribute to abnormal immune recognition in susceptible individuals.

Because antisynthetase syndrome targets intracellular enzymes involved in protein translation, researchers may eventually investigate whether microbial antigen exposure participates in loss of tolerance.

At present, this remains speculative.

Why Could the Lung Be a Site of Autoimmune Initiation?

One interesting possibility in autoimmune ILD is that the lung is not merely a target organ.

It may also participate in the development of autoimmune responses.

Respiratory epithelial injury, environmental exposure and microbial stimulation could create conditions in which intracellular proteins are released or modified.

This could contribute to antigen presentation and autoimmune activation.

The concept resembles mucosal-origin models proposed in rheumatoid arthritis.

Whether this specifically contributes to antisynthetase autoantibody development is still uncertain.

Environmental Exposures May Interact With the Microbiome

The respiratory tract is continuously exposed to:

• air pollution

• occupational particles

• tobacco smoke

• infectious agents

• organic antigens

These exposures can modify:

• airway epithelial integrity

• pulmonary immunity

• lung microbiota

Therefore, future research may need to consider the interaction between:

environment + microbiome + immune phenotype + genetics

rather than looking at microbes in isolation.

Could the Microbiome Explain Anti-Jo-1 Versus PL-7/PL-12 Disease?

Not yet.

We know that different antisynthetase antibodies are associated with different clinical patterns.

Anti-PL-7 and anti-PL-12 disease frequently has prominent pulmonary involvement, while anti-Jo-1 disease may have a different balance of myositis, arthritis and ILD. (PubMed⁠)

But there are insufficient microbiome data to determine whether microbial factors explain these differences.

This would be a valuable research direction.

Can the Microbiome Predict ILD Progression?

No validated microbiome biomarker currently predicts the trajectory of antisynthetase-associated ILD.

Recent 2026 research demonstrates that antisynthetase ILD follows different longitudinal trajectories and that predicting clinical course remains a major challenge. (PubMed⁠)

Microbial biomarkers might eventually contribute to such models.

But that is a future possibility.

Can a Commercial Stool Test Tell Whether Antisynthetase ILD Will Progress?

No.

There is currently no commercial microbiome test validated to predict:

• development of antisynthetase syndrome

• presence of ILD

• progression of ILD

• relapse

• response to immunosuppression

• prognosis

Research microbiome sequencing should not be confused with commercial stool testing.

Can BAL Microbiome Testing Be Used Clinically?

Not currently for routine antisynthetase management.

BAL may be clinically useful in selected ILD patients for specific diagnostic questions, particularly when infection or other competing diagnoses are considered.

But performing BAL purely to characterize the microbiome is currently a research strategy.

There is no validated BAL microbiome threshold that dictates antisynthetase treatment.

Do Probiotics Treat Antisynthetase ILD?

No clinical evidence supports probiotics as treatment for antisynthetase syndrome-associated ILD.

No probiotic has been shown to:

• improve FVC

• improve DLCO

• prevent progression

• reduce relapses

• improve survival

Probiotics may have separate gastrointestinal indications.

They should not be promoted as immunosuppressive or antifibrotic treatment.

What About Prebiotics or Butyrate?

Theoretical microbiome pathways involving SCFAs are scientifically interesting.

But there are currently no clinical trials demonstrating that:

• fiber manipulation

• prebiotics

• butyrate

• postbiotics

modify antisynthetase ILD outcomes.

This remains experimental.

Does Treating Gut Dysbiosis Reduce Autoantibodies?

There is no evidence that a microbiome intervention reliably eliminates:

• anti-Jo-1

• anti-PL-7

• anti-PL-12

• other antisynthetase antibodies

or treats the underlying syndrome.

Claims that “healing the gut” can eliminate antisynthetase syndrome are not supported by current clinical evidence.

What Treatments Are Actually Established?

Antisynthetase ILD generally requires specialist immunomodulatory treatment.

The evidence base is imperfect because randomized trials specifically dedicated to antisynthetase ILD remain limited, but current management uses combinations of corticosteroids and steroid-sparing immunosuppressive agents according to disease severity and phenotype. (PubMed⁠)

Potential therapies may include, depending on the clinical context:

• mycophenolate

• tacrolimus or other calcineurin inhibitors

• rituximab

• cyclophosphamide

• additional immunomodulatory strategies

Treatment needs to be individualized by clinicians experienced in autoimmune ILD.

Relapse and Recurrence Matter

Even after initial improvement, antisynthetase ILD can recur.

A 2026 study specifically examined factors associated with recurrence of antisynthetase-associated ILD, reinforcing that long-term disease monitoring remains important. (PubMed⁠)

This is another reason experimental microbiome interventions should not replace established follow-up.

Patients require serial assessment of:

• symptoms

• pulmonary function

• imaging where appropriate

• oxygenation

• autoimmune disease activity

Functional and Integrative Medicine Perspective

Antisynthetase syndrome is a useful example of how integrative care should be structured.

The central disease must first be correctly phenotyped.

That means identifying:

• antibody subtype

• HRCT pattern

• lung-function trajectory

• myositis activity

• arthritis

• oxygenation

• progression risk

Then broader health factors can be addressed.

These may include:

• nutritional status

• gastrointestinal symptoms

• reflux

• metabolic health

• muscle preservation

• sleep

• physical activity

• environmental exposures

• medication effects

This is a more defensible model than attempting to treat the autoimmune ILD through the microbiome alone.

Why Muscle Health Is Especially Important

Unlike many other ILDs, antisynthetase syndrome may directly impair skeletal muscle.

This creates a particularly important interaction between:

lung function + muscle function + nutrition + rehabilitation

A patient’s exercise limitation may reflect both:

• pulmonary impairment

• inflammatory muscle weakness

Preserving nutritional status and muscle mass is therefore especially important.

Overly restrictive diets intended to “heal the microbiome” could be counterproductive in patients already at risk of muscle loss.

What We Know

Current evidence supports several conclusions.

We know that:

• ILD is a major determinant of outcome in antisynthetase syndrome

• pulmonary phenotype varies according to antisynthetase antibody

• the lower-airway microbiome may differ according to anti-Jo-1 status

• Veillonella abundance differed between anti-Jo-1-positive and non-Jo-1 patients in one BAL study

• airway microbial abundance correlated with inflammatory-cell populations

(PubMed⁠)

These observations make microbial–immune interactions a credible research target.

What We Do Not Know

We do not yet know whether:

• gut dysbiosis causes antisynthetase syndrome

• the gut microbiome differs consistently between Jo-1 and PL-7/PL-12 disease

• airway microbiome changes precede ILD

• Veillonella contributes causally to pulmonary injury

• microbiome modification changes FVC

• probiotics reduce relapse

• butyrate changes disease progression

• commercial stool testing predicts prognosis

The disease-specific microbiome literature remains small.

The Major Limitation: Sample Size

The most directly relevant lung microbiome study involved only:

• 6 anti-Jo-1-positive patients

• 17 non-Jo-1 patients

(PubMed⁠)

Such a small cohort cannot establish a universal microbial signature.

Larger multicenter studies are necessary.

What Should Future Research Look Like?

An ideal antisynthetase microbiome study would recruit a large international cohort stratified by:

• anti-Jo-1

• anti-PL-7

• anti-PL-12

• anti-EJ

• other ARS antibodies

and characterize:

• stool metagenome

• oral microbiome

• lung microbiome

• serum metabolome

• immune phenotype

Patients would then undergo longitudinal assessment of:

• FVC

• DLCO

• HRCT

• treatment response

• relapse

• progressive pulmonary fibrosis

• survival

This could reveal whether microbial signatures are simply associated with established disease or actually precede different clinical trajectories.

From Gut–Lung Axis to Mucosal Network

Ultimately, antisynthetase syndrome may require a broader concept than the gut–lung axis.

A more realistic model may be:

gut microbiome
↕
systemic immunity
↕
oral microbiome
↕
lung microbiome
↕
pulmonary epithelial injury
↕
autoimmune response

This can be thought of as a mucosal–immune–lung network.

Such a model better reflects the complexity of autoimmune lung disease.

What Does This Mean for Patients Today?

Microbiome research is scientifically interesting, but it is not currently a reason to delay established treatment.

A patient with antisynthetase syndrome and ILD needs appropriate assessment of:

• pulmonary disease severity

• antibody phenotype

• lung-function trajectory

• HRCT findings

• oxygen requirement

• treatment response

• possible relapse or progression

Gastrointestinal symptoms, nutritional status and lifestyle factors also deserve attention.

But there is currently no evidence-based “antisynthetase microbiome protocol.”

Conclusion

The microbiome may ultimately contribute to our understanding of antisynthetase syndrome-associated interstitial lung disease.

The strongest disease-specific evidence currently comes from the lung microbiome, where a small bronchoalveolar lavage study found differences between anti-Jo-1-positive and non-Jo-1 patients and identified relationships between Veillonella, Prevotella and pulmonary immune-cell populations. (PubMed⁠)

That finding is intriguing.

But the evidence remains early.

We do not yet have a well-defined antisynthetase gut microbiome signature, nor evidence that treating intestinal dysbiosis changes the course of ILD.

This distinction is particularly important because microbiome research can easily be overinterpreted.

The appropriate conclusion is not:

“Antisynthetase ILD is caused by the gut.”

It is:

“Mucosal microbial environments may interact with immune and pulmonary phenotypes in antisynthetase syndrome, and this interaction deserves much more rigorous investigation.”

Future research integrating the gut, oral and lung microbiomes with metabolomics, autoantibody phenotype and longitudinal lung outcomes may help explain why antisynthetase-associated ILD behaves so differently between patients.

That could eventually lead to new biomarkers or therapeutic targets.

For now, microbiome science should complement—not replace—the established framework of autoimmune ILD care.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical and academic interests include Integrative and Functional Pulmonology, autoimmune-associated ILD, the gut–lung axis, lung microbiome, nutrition, metabolic health and emerging microbial mechanisms in chronic lung disease.

Living With Antisynthetase Syndrome and ILD?

If you have anti-Jo-1, PL-7, PL-12 or another antisynthetase antibody with interstitial lung disease and would like a comprehensive assessment combining specialist pulmonary expertise with an evidence-based functional and integrative perspective, you can explore the available online consultation options.

The assessment can consider your pulmonary disease together with relevant nutritional, gastrointestinal, metabolic and lifestyle factors while remaining anchored to evidence-based ILD treatment.

Contact us through the consultation page or WhatsApp to learn more.

Functional and integrative care is intended to complement—not replace—appropriate pulmonary, rheumatological and immunomodulatory treatment.

Medical Disclaimer: This article is educational and does not constitute individualized medical advice. Antisynthetase syndrome-associated ILD requires appropriate specialist evaluation and treatment.

Gut Microbiome and Myositis-Associated Interstitial Lung Disease: Could Dysbiosis Be Linked to Rapidly Progressive ILD?

Could the Gut Microbiome Be Linked to Severe Lung Disease in Myositis?

Idiopathic inflammatory myopathies, or IIMs, are a heterogeneous group of autoimmune diseases that can affect skeletal muscle, skin, joints and internal organs.

Among their most important complications is interstitial lung disease, or ILD.

In some patients, ILD develops gradually.

In others, particularly certain autoimmune phenotypes, lung disease may progress over weeks or months and become life-threatening.

This aggressive phenotype is known as:

rapidly progressive interstitial lung disease, or RP-ILD.

The causes of this marked variation remain incompletely understood.

Autoantibodies, genetics and immune pathways clearly matter.

But researchers have begun asking another question:

Could the intestinal microbiome help influence which patients develop chronic ILD and which develop rapidly progressive disease?

Human evidence remains very limited.

However, an important metagenomic study has provided preliminary evidence that patients with myositis-associated RP-ILD may have intestinal microbial patterns that differ from those with chronic ILD. (PubMed⁠)

This is scientifically interesting because it moves the discussion beyond simply asking whether myositis is associated with dysbiosis.

The more clinically important question becomes:

Could the microbiome relate to the pulmonary phenotype and severity of autoimmune ILD?

At present, the answer is possible—but far from proven.

What Is Myositis-Associated ILD?

Idiopathic inflammatory myopathies include several autoimmune disorders, including:

• dermatomyositis

• polymyositis

• antisynthetase syndrome

• immune-mediated necrotizing myopathy

• clinically amyopathic dermatomyositis

ILD is a major pulmonary manifestation of these disorders and may occasionally appear before obvious muscle symptoms.

The spectrum ranges from relatively indolent disease to rapidly progressive respiratory failure. Current 2026 literature continues to emphasize substantial heterogeneity and the importance of myositis-specific autoantibodies in defining clinical phenotypes. (PubMed⁠)

This heterogeneity is crucial when discussing microbiome research.

There may not be one single “myositis microbiome.”

Different autoimmune phenotypes may potentially have different microbial and metabolic signatures.

Why Is Rapidly Progressive ILD So Important?

RP-ILD can deteriorate over a short period and is associated with substantial morbidity and mortality.

It is particularly recognized in patients with certain dermatomyositis phenotypes.

One of the best-known associations is with:

anti-MDA5 antibody-positive dermatomyositis.

Other myositis-specific and myositis-associated antibodies can also help define pulmonary risk.

Myositis-associated ILD therefore provides an especially interesting model for studying whether biological markers—including the microbiome—could eventually help identify distinct disease phenotypes.

The Current Human Microbiome Evidence

The most directly relevant human study was published in Clinical Immunology in 2023.

Researchers performed a metagenome-wide association study using high-depth whole-genome shotgun sequencing.

The study included:

• 30 patients with myositis

• 31 healthy controls

Among the 30 myositis patients:

• 11 had rapidly progressive ILD

• 10 had chronic ILD

This is a small study.

But it is important because it directly compared microbial characteristics between patients with different ILD trajectories. (PubMed⁠)

What Was Different in Myositis Overall?

Compared with healthy controls, patients with myositis had increased abundance of organisms including:

• Alistipes onderdonkii

• Parabacteroides distasonis

• Escherichia coli

They had decreased abundance of organisms including:

• Roseburia intestinalis

• Akkermansia muciniphila

• a Lachnospiraceae bacterium

The investigators also identified differences in microbial metabolic pathways. (PubMed⁠)

These findings suggest that myositis is associated with altered intestinal microbial ecology.

However, they do not tell us whether the dysbiosis:

• preceded autoimmunity

• resulted from autoimmune disease

• reflected medications

• reflected diet

• resulted from reduced physical activity or disease severity

Causality cannot be determined from this design.

What Was Different in Rapidly Progressive ILD?

The most interesting comparison involved RP-ILD versus chronic ILD.

Patients with rapidly progressive disease demonstrated increased abundance of organisms including:

• Bacteroides thetaiotaomicron

• Parabacteroides distasonis

• Escherichia coli

and lower abundance of:

• Bacteroides A1C1

• Bacteroides xylanisolvens

compared with patients who had chronic ILD. (PubMed⁠)

These differences raise the possibility that severe pulmonary phenotypes are associated with different intestinal microbial ecosystems.

But the sample sizes—11 RP-ILD and 10 chronic ILD—are extremely small.

The findings should therefore be considered hypothesis-generating, not diagnostic.

Roseburia intestinalis: An Interesting Finding

One organism deserves particular attention:

Roseburia intestinalis.

Roseburia species are generally known for their capacity to participate in production of short-chain fatty acids, especially butyrate.

In the study, R. intestinalis was reduced in myositis and showed potential discriminatory value when comparing RP-ILD with chronic ILD. (PubMed⁠)

This is biologically intriguing because butyrate influences:

• intestinal-barrier integrity

• regulatory T cells

• inflammatory signaling

• immune tolerance

However, several important steps are missing.

Reduced Roseburia does not automatically prove:

• reduced systemic butyrate activity

• increased pulmonary inflammation

• causation of RP-ILD

• benefit from butyrate supplementation

The finding provides a mechanistic clue—not a treatment protocol.

Escherichia coli: Why Did It Attract Attention?

The investigators found increased Escherichia coli in myositis and in the RP-ILD subgroup.

They also found that E. coli contributed importantly to altered microbial metabolic pathways identified in both myositis and RP-ILD. (PubMed⁠)

This may be biologically relevant because Gram-negative bacteria contain lipopolysaccharide, or LPS, in their outer membrane.

LPS can activate innate immune pathways such as:

TLR4 → NF-κB

leading to inflammatory cytokine signaling.

This generates a plausible hypothesis:

dysbiosis with greater pro-inflammatory microbial activity → altered systemic immune signaling → more severe autoimmune pulmonary inflammation

But this remains speculative.

The study did not demonstrate that intestinal E. coli or circulating LPS caused RP-ILD.

Microbial Metabolic Pathways May Matter More Than Individual Bacteria

One of the most valuable aspects of shotgun metagenomic sequencing is that it can investigate microbial functional pathways, not just bacterial abundance.

The 2023 study found multiple metabolic pathways that differed between:

• myositis and healthy controls

• RP-ILD and chronic ILD

and identified E. coli as an important contributor to several pathway differences. (PubMed⁠)

This supports an emerging principle in microbiome science:

What the microbiome does may ultimately matter more than which organisms are present.

Future research is therefore likely to focus on:

• microbial metabolites

• amino-acid metabolism

• SCFAs

• bile acids

• immune-active bacterial products

• metabolomic signatures

  About Dr. Samar Shadly

  Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

  Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

  A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

  Living with Pulmonary Fibrosis or Interstitial Lung Disease?

  If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

  To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

  Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

Gut Microbiome and Rheumatoid Arthritis–Associated Interstitial Lung Disease: What Does the Evidence Show?

Could the Gut Microbiome Help Explain Why Some People With Rheumatoid Arthritis Develop ILD?

Rheumatoid arthritis is best known as an inflammatory joint disease.

But it is a systemic autoimmune disease, and the lungs are among its most important extra-articular targets.

Interstitial lung disease can occur in a subset of patients with rheumatoid arthritis and may range from relatively limited abnormalities to progressive pulmonary fibrosis.

This condition is known as rheumatoid arthritis-associated interstitial lung disease, or RA-ILD.

One of the major unanswered questions is why certain patients with rheumatoid arthritis develop clinically important lung disease while others never do.

Known contributors include:

• age

• male sex

• smoking

• rheumatoid factor

• anti-citrullinated protein antibodies

• genetics

• disease characteristics

• environmental factors

But these factors do not explain everything.

An emerging area of research asks whether mucosal immunity and the microbiome might contribute to the pulmonary phenotype of rheumatoid arthritis.

This hypothesis is particularly interesting because abnormal immune responses at mucosal surfaces may begin years before joint symptoms appear.

The intestine, oral cavity and lungs are therefore increasingly being considered as interconnected immune environments rather than isolated organs.

Recent human microbiome studies have now directly compared patients with RA-ILD against rheumatoid arthritis patients without ILD.

The findings are intriguing.

But they are also inconsistent enough to require caution.

That combination makes RA-ILD one of the most important areas for careful, evidence-based gut–lung research.

What Is Rheumatoid Arthritis–Associated ILD?

RA-ILD refers to interstitial lung disease occurring in association with rheumatoid arthritis.

The most frequent HRCT patterns include:

• usual interstitial pneumonia, or UIP

• nonspecific interstitial pneumonia, or NSIP

Other patterns can occur.

The clinical course is highly variable.

Some patients have mild stable disease.

Others develop progressive pulmonary fibrosis characterized by:

• worsening breathlessness

• declining exercise capacity

• falling FVC

• impaired DLCO

• increasing fibrosis on imaging

RA-ILD is clinically important because pulmonary involvement contributes substantially to morbidity and mortality in rheumatoid arthritis.

Understanding why it occurs is therefore a major research priority.

Why Is the Microbiome Already Important in Rheumatoid Arthritis?

Long before researchers focused specifically on RA-ILD, the gut microbiome had become an important field in rheumatoid arthritis itself.

RA is increasingly understood through the concept of mucosal origins of autoimmunity.

This hypothesis proposes that abnormal immune responses may begin at mucosal surfaces such as:

• the gastrointestinal tract

• oral cavity

• respiratory tract

before clinically obvious joint disease develops.

One clue is the presence of autoantibodies such as:

• anti-citrullinated protein antibodies, or ACPA

• rheumatoid factor

before arthritis becomes clinically apparent.

The gut microbiome may influence these immune responses through:

• mucosal barrier function

• antigen exposure

• T-cell regulation

• microbial metabolites

• molecular mimicry

• post-translational protein modification

Recent 2026 reviews continue to support a mechanistic role for gut dysbiosis in rheumatoid autoimmunity while emphasizing that the exact causal pathways remain incompletely defined. (PubMed⁠)

Why Ask a Separate Question About RA-ILD?

Because the microbiome associated with rheumatoid arthritis is not necessarily the same as the microbiome associated with rheumatoid lung involvement.

This distinction matters.

If both patients with RA-ILD and those with RA without lung disease show the same microbial alterations, the microbiome may be related mainly to rheumatoid autoimmunity.

But if RA-ILD patients show additional microbial characteristics that distinguish them from RA patients without ILD, those features might potentially relate to the pulmonary phenotype.

That is the critical scientific comparison.

And recent studies have attempted exactly that.

The 2024 Multikingdom Metagenomic Study

One important study used whole-metagenome shotgun sequencing to compare:

• 30 patients with RA-ILD

• 30 patients with RA without ILD

• 40 matched healthy controls

Rather than studying bacteria alone, investigators examined three microbial kingdoms:

• bacteriome

• mycobiome

• virome

This is an important methodological advance because the intestinal ecosystem includes far more than bacteria.

The study found substantial alterations in gut microbial composition in both rheumatoid arthritis groups compared with healthy controls.

Across the study population, investigators identified differences involving hundreds of bacterial species, dozens of fungal species and thousands of viral operational taxonomic units. (PubMed⁠)

Which Bacteria Were Different?

Several bacterial changes were shared by patients with rheumatoid arthritis regardless of lung involvement.

For example, organisms including:

• Bifidobacterium longum

• Dorea formicigenerans

• Collinsella aerofaciens

were enriched in both RA groups.

Meanwhile, potentially health-associated organisms such as:

• Faecalibacterium prausnitzii

• several Bacteroides species

• Roseburia inulinivorans

were reduced in both groups.

These findings suggest that a substantial part of the microbial signature may reflect rheumatoid arthritis itself, not necessarily ILD. (PubMed⁠)

Was Anything Unique to RA-ILD?

Yes.

The 2024 study reported certain microbial features that appeared relatively enriched in the RA-ILD group.

One notable organism was:

Ruminococcus gnavus

which was described as uniquely enriched in RA-ILD relative to the comparison groups in that analysis. (PubMed⁠)

This organism has attracted attention in other immune-mediated diseases because some strains may possess pro-inflammatory properties.

However, microbiome findings are context-dependent.

An association with RA-ILD does not demonstrate that R. gnavus causes lung fibrosis.

It may instead be:

• a marker of altered immunity

• a consequence of medications

• related to diet or geography

• linked with rheumatoid disease severity

Replication is necessary before it can be considered a reliable RA-ILD biomarker.

The Mycobiome: What About Fungi?

One of the strengths of the 2024 study was that it did not stop at bacteria.

The mycobiome refers to the fungal component of the microbiome.

Compared with healthy participants, the rheumatoid arthritis groups showed depletion of certain fungi, including:

• Saccharomyces cerevisiae

• Candida albicans

This is an interesting finding because it challenges the oversimplified idea that more Candida automatically means greater autoimmune disease.

Microbial ecology is much more complicated than classifying organisms as universally “good” or “bad.” (PubMed⁠)

The Virome: Viruses Also Matter

The study also identified substantial differences in the intestinal virome.

Most gut viruses are bacteriophages—viruses that infect bacteria.

They can influence:

• bacterial abundance

• bacterial gene expression

• microbial competition

• ecosystem stability

The rheumatoid arthritis groups demonstrated changes in several viral families, including increased Siphoviridae and reductions in several others.

The biological implications remain uncertain, but this finding reinforces an important principle:

The gut microbiome is an ecosystem of bacteria, fungi and viruses—not merely a list of bacterial species. (PubMed⁠)

A Separate Comparative Study: Prevotella and RA-ILD

Another human comparative study evaluated:

• 30 patients with RA-ILD

• 31 patients with RA without ILD

• 30 healthy controls

using 16S rRNA sequencing.

Investigators reported significant differences in microbial composition among groups.

The genus Prevotella emerged as one of the organisms showing differential abundance, and predicted microbial functional analysis suggested changes in several metabolic pathways in RA-ILD. (PubMed⁠)

This adds additional evidence that RA-ILD may possess a microbial phenotype distinguishable from rheumatoid arthritis alone.

However, sequencing methods and statistical approaches differed from those used in the other studies.

This can make direct comparisons difficult.

What Is Special About Prevotella?

Prevotella has been extensively studied in rheumatoid arthritis.

Certain Prevotella species, especially Prevotella copri, have been associated with early or untreated RA in some populations.

Potential mechanisms include:

• mucosal immune activation

• Th17-related responses

• altered intestinal-barrier function

• antigenic stimulation

But Prevotella is a diverse genus.

Different strains may have different effects.

Diet also strongly influences Prevotella abundance.

Therefore, finding more Prevotella does not automatically mean that it is pathogenic.

Its significance depends on:

• species

• strain

• host immune context

• dietary environment

• microbial community

The Important 2026 Study: A More Cautious Result

A newer study published in June 2026 used shotgun metagenomic sequencing to compare:

• 10 patients with RA-ILD

• 20 patients with RA without ILD

• 11 healthy controls

for a total of 41 participants.

This study is particularly useful because its results were more conservative.

There were no significant differences in alpha or beta diversity among the groups.

More importantly, after appropriate correction for multiple statistical comparisons, no genus remained significantly different between RA-ILD and RA without ILD. (PubMed⁠)

This is scientifically important.

It means that we should not present a definitive RA-ILD microbial signature as established fact.

What Did the Exploratory 2026 Analysis Show?

Before correction for multiple comparisons, the investigators observed exploratory differences.

RA-ILD showed enrichment of:

Escherichia/Shigella

and depletion of organisms including:

Roseburia.

The reported abundance of Escherichia/Shigella was substantially higher in RA-ILD than in RA without ILD in the exploratory analysis. (PubMed⁠)

However, because these differences did not survive FDR correction, they should be considered hypothesis-generating rather than definitive.

That distinction is essential.

Why Does FDR Correction Matter?

Microbiome studies can test hundreds or thousands of organisms simultaneously.

If enough comparisons are made, some differences will appear statistically significant simply by chance.

False discovery rate correction adjusts for this problem.

When a result disappears after FDR correction, it does not mean the observation is necessarily false.

It means the evidence is not strong enough to confidently distinguish it from chance within that dataset.

This is why the 2026 findings should not be translated into statements such as:

“Escherichia causes RA-ILD.”

The evidence does not support that conclusion.

What About Roseburia?

Roseburia is interesting because several species are associated with production of butyrate, a short-chain fatty acid.

Butyrate can influence:

• intestinal epithelial health

• immune regulation

• Treg activity

• inflammatory signaling

The exploratory depletion of Roseburia in RA-ILD therefore raises a plausible mechanistic hypothesis:

loss of butyrate-associated microbial function → altered immune regulation → greater systemic or pulmonary inflammatory signaling

But the evidence remains indirect.

A lower relative abundance of Roseburia does not automatically prove a clinically important butyrate deficiency.

And giving butyrate has not been shown to treat RA-ILD.

Clinical Correlations in the 2026 Study

The newer study also examined relationships between microbial patterns and clinical characteristics.

Certain butyrate-associated organisms showed inverse relationships with measures of rheumatoid disease activity.

This suggests that microbial metabolism may relate to systemic inflammatory burden. (PubMed⁠)

Again, correlation does not tell us direction.

More active rheumatoid disease could alter the microbiome.

Or the microbiome could influence immune activity.

Or both could be influenced by medications, diet or other factors.

Why Are the Studies Not Identical?

This is expected in microbiome science.

Potential reasons include differences in:

• sample size

• ethnicity

• geography

• diet

• medication exposure

• rheumatoid disease activity

• ILD severity

• smoking

• sequencing method

• bioinformatic pipeline

• statistical correction

Even sample collection and storage can affect results.

Therefore, individual bacterial findings should be interpreted cautiously until replicated across independent populations.

The Most Defensible Conclusion From Human Evidence

The current evidence supports the statement that:

Patients with RA-ILD appear to have alterations in intestinal microbial ecology, but a reproducible gut microbial signature that clearly distinguishes RA-ILD from rheumatoid arthritis without ILD has not yet been established.

That is a stronger scientific statement than claiming a specific bacterium causes the disease.

How Could the Gut Microbiome Influence RA-ILD?

Several mechanisms are plausible.

1. Mucosal Autoimmunity

Rheumatoid arthritis may begin partly at mucosal surfaces.

Environmental exposure and microbial signals could lead to local inflammation and protein modification.

In genetically susceptible individuals, these processes may contribute to development of autoantibodies such as ACPA.

The lung itself may also be a site of protein citrullination and immune activation.

This creates a potential mucosal network involving:

gut + mouth + lung + systemic immunity

rather than a simple gut-to-lung pathway.

2. Treg and Th17 Balance

Gut microorganisms influence the differentiation of immune cells.

Two particularly important populations are:

• regulatory T cells

• Th17 cells

Excessive Th17 activity and impaired regulatory responses are implicated in rheumatoid arthritis.

Dysbiosis could potentially shift this balance toward inflammatory immunity.

That systemic immune environment may then influence pulmonary inflammation and fibrosis.

Recent 2026 reviews of rheumatoid autoimmunity continue to identify altered Treg/Th17 signaling as one important microbiome-related pathway. (PubMed⁠)

3. Intestinal Permeability

Another proposed mechanism involves intestinal-barrier function.

Tight junctions normally regulate movement of microbial molecules from the intestinal lumen into circulation.

Increased intestinal permeability has been investigated in rheumatoid arthritis.

If barrier integrity is impaired, microbial products may gain greater systemic exposure.

This may amplify innate and adaptive immune activation.

Recent 2026 literature specifically reviews the relationship between gut dysbiosis, intestinal permeability and rheumatoid arthritis pathogenesis. (PubMed⁠)

Whether this mechanism specifically drives RA-ILD remains unknown.

4. Lipopolysaccharide and Innate Immunity

Gram-negative bacterial products such as LPS can activate:

TLR4 → NF-κB

and stimulate inflammatory cytokines.

These pathways are relevant to both rheumatoid autoimmunity and pulmonary inflammatory responses.

In theory, greater microbial translocation could amplify systemic inflammation and affect the pulmonary microenvironment.

Direct causal human evidence in RA-ILD is still lacking.

5. Short-Chain Fatty Acids

Microbial fermentation produces:

• acetate

• propionate

• butyrate

SCFAs help regulate mucosal immunity and intestinal-barrier health.

The possible depletion of some butyrate-associated bacterial groups in RA-ILD makes this pathway especially interesting.

However:

butyrate-associated bacteria are not equivalent to measured butyrate activity, and neither has been established as a treatment target in RA-ILD.

6. Molecular Mimicry and Antigenic Stimulation

Microbial proteins can sometimes resemble human proteins closely enough to influence immune recognition.

This phenomenon is called molecular mimicry.

In genetically susceptible individuals, prolonged microbial exposure could theoretically contribute to abnormal autoreactive immune responses.

This has been proposed within rheumatoid arthritis pathogenesis.

Its specific relevance to pulmonary fibrosis remains uncertain.

7. Microbial Metabolites

Beyond SCFAs, intestinal microbes produce:

• tryptophan metabolites

• bile-acid derivatives

• amino-acid metabolites

• microbial peptides

These can influence systemic immune-cell function.

Future RA-ILD research may therefore focus less on individual bacterial names and more on microbial metabolic pathways.

This may ultimately prove more informative.

The Gut Is Not the Only Mucosal Site in RA-ILD

A key limitation of a purely gut-centered model is that rheumatoid arthritis may involve several mucosal ecosystems.

The oral microbiome has been extensively studied in RA.

Periodontal organisms and chronic oral inflammation may influence protein citrullination and autoimmune responses.

The lung also has its own microbiome and mucosal immune environment.

Therefore, the more accurate model may be:

gut–oral–lung–joint axis

rather than a one-directional gut–lung axis.

Smoking Adds Another Layer

Smoking is an established risk factor for RA-ILD and is particularly relevant in ACPA-positive rheumatoid arthritis.

Smoking can also alter:

• respiratory microbiota

• oral microbiota

• intestinal microbiota

• mucosal immunity

This creates an important confounding problem.

Some microbial differences attributed to RA-ILD could partly reflect smoking-related biology.

Good microbiome studies therefore need careful adjustment for smoking exposure.

Medications Also Matter

Patients with rheumatoid arthritis may receive:

• methotrexate

• corticosteroids

• biologic therapies

• JAK inhibitors

• antibiotics

• proton-pump inhibitors

• NSAIDs

Each can potentially influence gastrointestinal physiology or microbial ecology.

Medication effects therefore need to be considered before interpreting an individual microbial signature as part of disease pathogenesis.

Does Gut Dysbiosis Cause RA-ILD?

At present, we cannot say that it does.

At least four possibilities remain:

Dysbiosis may contribute to disease.

Rheumatoid inflammation may alter the microbiome.

RA-ILD treatment or severity may alter the microbiome.

Shared environmental or immune factors may produce both.

A bidirectional model is likely.

Can the Gut Microbiome Predict Who Will Develop RA-ILD?

Not currently.

Research studies suggest microbial signatures may eventually have biomarker potential.

But no microbiome test has been validated to predict:

• which RA patient will develop ILD

• when ILD will begin

• whether disease will progress

• what HRCT pattern will occur

Established clinical risk factors remain much more useful today.

Can Commercial Stool Testing Diagnose RA-ILD?

No.

Research-grade shotgun metagenomics is not equivalent to a commercial stool microbiome report.

At present, no commercial stool test can determine:

• whether a patient has RA-ILD

• whether their fibrosis will progress

• which rheumatological therapy should be used

• whether antifibrotic treatment is required

• which probiotic will improve lung disease

Commercial testing should not replace:

• pulmonary function testing

• HRCT

• rheumatological assessment

• specialist ILD evaluation

Should Patients With RA-ILD Take Probiotics?

There is no probiotic currently established as treatment for RA-ILD.

A probiotic may have a role for a separate gastrointestinal indication.

That is different from using it to modify pulmonary fibrosis.

No randomized human trial has shown that probiotics:

• improve FVC

• improve DLCO

• slow fibrotic progression

• reduce mortality

in RA-ILD.

What About Prebiotics or Fiber?

Diet influences the intestinal microbiome and SCFA production.

Supporting a nutritionally adequate dietary pattern may benefit:

• metabolic health

• bowel function

• microbial diversity

• cardiovascular risk

But there is no clinical evidence that increasing fiber specifically treats RA-ILD.

Dietary recommendations must also consider gastrointestinal tolerance and overall nutritional status.

Can Butyrate Treat RA-ILD?

No clinical evidence currently supports butyrate as treatment for RA-ILD.

The interest comes from:

• butyrate-producing bacterial groups

• Treg regulation

• intestinal-barrier effects

• anti-inflammatory properties

These are mechanistic arguments.

They are not evidence of pulmonary therapeutic efficacy.

Could Microbiome Therapy Become Relevant in the Future?

Possibly.

Future strategies could include:

• precision prebiotics

• defined microbial consortia

• postbiotics

• targeted metabolites

• engineered bacteria

• personalized dietary interventions

But future trials will need to show improvement in genuine pulmonary outcomes.

Changing stool bacteria alone will not be sufficient.

What Outcomes Would Matter?

A meaningful RA-ILD microbiome trial should evaluate outcomes such as:

• FVC decline

• DLCO

• HRCT progression

• symptoms

• exercise capacity

• progressive pulmonary fibrosis

• hospitalization

• survival

It should also control for:

• rheumatoid disease activity

• medications

• smoking

• diet

• antibiotics

• ILD pattern

Only then can causality begin to be addressed.

Functional and Integrative Medicine Perspective

RA-ILD requires genuine integration between rheumatology and pulmonary medicine.

An evidence-based functional and integrative approach can broaden the assessment to include:

• gastrointestinal symptoms

• nutrition

• metabolic health

• smoking

• oral health

• sleep

• exercise

• muscle mass

• relevant environmental exposures

But this broader approach must remain anchored to the actual pulmonary phenotype.

Patients still require appropriate evaluation of:

• HRCT pattern

• lung function

• disease progression

• oxygen requirement

• pulmonary hypertension when relevant

• immunomodulatory therapy

• antifibrotic therapy where appropriate

• pulmonary rehabilitation

Gut health may become an additional layer.

It should not replace these priorities.

What We Know

Current human evidence shows that:

• RA is associated with gut dysbiosis

• RA-ILD patients also demonstrate altered intestinal microbial patterns

• a 2024 multikingdom metagenomic study identified bacterial, fungal and viral alterations in RA-ILD

• another comparative study identified differences involving Prevotella and predicted metabolic pathways

• a 2026 shotgun metagenomic study found exploratory RA-ILD differences involving Escherichia/Shigella and Roseburia

(PubMed⁠)

What We Do Not Know

The newer evidence also tells us what not to claim.

In the 2026 study:

• alpha diversity was not significantly different

• beta diversity was not significantly different

• no genus remained significantly different between RA-ILD and RA without ILD after FDR correction

(PubMed⁠)

Therefore, a definitive RA-ILD gut microbial signature has not yet been established.

We also do not know whether:

• dysbiosis precedes lung disease

• changing dysbiosis prevents RA-ILD

• microbiome treatment slows progression

• butyrate modification improves lung function

• probiotics alter survival

What Does the Evidence Mean Clinically?

The microbiome is a credible research target in RA-ILD.

It may help us eventually understand why certain patients develop pulmonary disease and others do not.

But microbiome-directed treatment is not ready for routine RA-ILD care.

For now, the most appropriate clinical approach is to:

1. identify and treat the RA-ILD correctly

2. control relevant autoimmune disease

3. monitor lung function and imaging

4. address smoking and respiratory risk factors

5. maintain nutrition and physical capacity

6. investigate clinically meaningful gastrointestinal problems when present

The microbiome sits within this framework—not above it.

Conclusion

The gut microbiome is emerging as a potentially important component of rheumatoid arthritis-associated interstitial lung disease.

Human studies now show that RA-ILD is associated with alterations across the intestinal bacteriome, mycobiome and virome, and some studies have identified microbial differences between RA-ILD and rheumatoid arthritis without lung disease.

However, the most recent 2026 metagenomic study also provides an important warning against overinterpretation: after correction for multiple comparisons, no genus significantly distinguished RA-ILD from RA without ILD.

That means the evidence currently supports association and biological plausibility—not a definitive microbial cause or diagnostic signature.

The next phase of research needs to move beyond asking:

“Which bacteria are different?”

and instead ask:

“Which microbial functions and metabolites influence rheumatoid immunity, which occur before lung disease, and can changing them modify the clinical course of RA-ILD?”

If those questions can be answered, microbiome science could eventually contribute to risk prediction, biomarkers or precision treatments for autoimmune ILD.

For now, it represents a promising research frontier within integrative pulmonology, rather than an established therapeutic strategy.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical approach combines evidence-based pulmonary medicine with functional and integrative medicine, with particular interest in autoimmune-associated interstitial lung disease, the gut–lung axis, nutrition, metabolic health and emerging microbiome science.

Living With Rheumatoid Arthritis and Interstitial Lung Disease?

If you have RA-associated interstitial lung disease and are looking for a comprehensive evaluation that considers your pulmonary disease together with relevant nutritional, gastrointestinal, metabolic and lifestyle factors, you can explore the available consultation options.

Contact us through the consultation page or WhatsApp to learn more about online consultations.

Functional and integrative care is intended to complement—not replace—appropriate rheumatological, pulmonary, immunomodulatory or antifibrotic treatment.

Medical Disclaimer: This article is educational and is not a substitute for individualized medical advice or specialist RA-ILD care.

SIBO and Systemic Sclerosis: Could Small Intestinal Bacterial Overgrowth Affect Lung Health?

Why Is SIBO So Common in Systemic Sclerosis?

Systemic sclerosis, also known as scleroderma, can affect far more than the skin.

The gastrointestinal tract is one of the most commonly involved organ systems.

Patients may experience:

• reflux

• difficulty swallowing

• early satiety

• bloating

• abdominal distension

• diarrhea

• constipation

• weight loss

• malabsorption

One particularly important gastrointestinal complication is small intestinal bacterial overgrowth, or SIBO.

SIBO occurs when the number or composition of microorganisms in the small intestine becomes abnormal.

This is especially relevant in systemic sclerosis because the disease can impair normal intestinal movement.

When intestinal contents move too slowly, bacteria have greater opportunity to accumulate and proliferate.

The result can be a cycle of:

intestinal dysmotility → bacterial overgrowth → fermentation → gastrointestinal symptoms → malabsorption and nutritional problems

But there is another reason SIBO has become interesting in systemic sclerosis.

Systemic sclerosis is also an important cause of interstitial lung disease (SSc-ILD).

And recent human research suggests that patients with SSc-ILD may have distinct gut microbial patterns.

This raises a fascinating question:

Could SIBO and intestinal dysbiosis have any relationship with lung disease in systemic sclerosis?

The answer requires careful interpretation.

SIBO is clinically important in systemic sclerosis.

The gut microbiome is increasingly associated with SSc-ILD.

But we do not currently have evidence proving that SIBO causes lung fibrosis—or that treating SIBO slows SSc-ILD.

Understanding this distinction is essential.

What Is SIBO?

The small intestine normally contains microorganisms, but its microbial population and density differ from those of the colon.

Several protective mechanisms help regulate this environment.

These include:

• gastric acid

• pancreatic and biliary secretions

• intestinal immune defenses

• normal anatomy

• coordinated intestinal motility

• the migrating motor complex

When these protective mechanisms are disrupted, microorganisms may accumulate excessively in the small intestine.

This is known as small intestinal bacterial overgrowth.

SIBO can interfere with digestion and nutrient absorption.

Depending on its severity and underlying cause, it may produce symptoms ranging from mild bloating to significant malnutrition.

Why Does Systemic Sclerosis Cause SIBO?

The major connection is gastrointestinal dysmotility.

Systemic sclerosis can affect the smooth muscle, nerves, connective tissue and blood vessels involved in gastrointestinal function.

As the disease progresses, intestinal contractions may become weaker or less coordinated.

Food and intestinal contents then move more slowly.

This creates an environment in which bacteria can accumulate.

A simplified pathway is:

systemic sclerosis
↓
intestinal neuromuscular dysfunction and fibrosis
↓
slower intestinal transit
↓
microbial stasis
↓
SIBO

This is why simply treating bacteria without addressing motility may result in recurrence.

How Common Is SIBO in Systemic Sclerosis?

SIBO is substantially more common in systemic sclerosis than in the general population.

Published estimates vary according to:

• diagnostic technique

• patient population

• disease severity

• definition of SIBO

Systematic reviews have estimated that approximately one-third to two-fifths of patients with systemic sclerosis may have SIBO, although individual studies report a broad range.

A recent 2025 review continues to identify SIBO as an important gastrointestinal manifestation of systemic sclerosis, closely linked with intestinal dysmotility and altered microbial ecology.

This makes SIBO one of the gastrointestinal conditions clinicians should actively consider when compatible symptoms are present.

What Are the Symptoms of SIBO in Systemic Sclerosis?

Symptoms may include:

• bloating

• abdominal distension

• excessive gas

• abdominal discomfort

• diarrhea

• constipation

• altered bowel habits

• nausea

• early satiety

More significant disease may contribute to:

• malabsorption

• weight loss

• vitamin deficiencies

• nutritional deterioration

However, symptoms are not specific.

Bloating does not automatically mean SIBO.

Systemic sclerosis itself can cause dysmotility and gastrointestinal symptoms even without bacterial overgrowth.

Other disorders may also produce similar symptoms.

Therefore, diagnosis should be based on the overall clinical picture rather than symptoms alone.

Why Does SIBO Matter in Someone With Lung Disease?

Even if SIBO does not directly cause pulmonary fibrosis, it can still be clinically relevant to a patient with SSc-ILD.

A patient with significant lung disease needs adequate:

• calories

• protein

• micronutrients

• muscle mass

• physical reserve

Chronic gastrointestinal symptoms can make this difficult.

If SIBO contributes to poor intake, diarrhea, malabsorption or weight loss, it may indirectly reduce the patient’s physiological reserve.

This becomes particularly important in advanced ILD, where maintaining muscle and nutritional status can affect:

• exercise capacity

• rehabilitation

• frailty

• quality of life

• transplantation candidacy

Therefore, gastrointestinal health should not be dismissed simply because we cannot yet prove a direct antifibrotic benefit.

Is SIBO the Same as Gut Dysbiosis?

No.

These terms are often used interchangeably online, but they describe different concepts.

SIBO refers specifically to abnormal microbial overgrowth or composition in the small intestine.

Gut dysbiosis is a broader term describing disruption of the intestinal microbial ecosystem.

A patient can have gut dysbiosis without SIBO.

A patient with SIBO will have abnormal microbial ecology in the small intestine, but this does not necessarily tell us what is happening in the colon.

This distinction becomes important when interpreting microbiome studies.

Most research microbiome studies analyze stool, which predominantly reflects distal intestinal microbial communities.

A stool microbiome analysis is therefore not equivalent to a SIBO breath test.

What Does SIBO Have to Do With the Gut–Lung Axis?

The gut–lung axis describes communication between intestinal and respiratory systems through immune and metabolic pathways.

Intestinal microorganisms produce compounds capable of influencing the host.

These include:

• short-chain fatty acids

• tryptophan metabolites

• bile-acid metabolites

• microbial peptides

• bacterial cell-wall components

If SIBO substantially changes intestinal microbial activity, it could theoretically alter the profile of these signals.

However, whether this has a clinically meaningful effect on SSc-ILD remains unknown.

What Does the New SSc-ILD Microbiome Evidence Show?

This is where the field has become particularly interesting.

An international study investigated 285 patients with systemic sclerosis from seven centers across five continents.

Approximately 62.5% had ILD.

Researchers used shotgun metagenomic sequencing to characterize intestinal microbial communities.

Patients with SSc-ILD demonstrated a distinct microbial signature compared with systemic sclerosis patients without ILD.

In addition, particular microbial species and microbial functional pathways were associated with the radiological extent of lung disease.

This provides important human evidence supporting a relationship between intestinal microbial biology and SSc-ILD.

But it is crucial to understand what the study did not demonstrate.

It did not show that SIBO causes SSc-ILD.

It did not show that treating SIBO improves pulmonary fibrosis.

And it did not establish a microbiome treatment for SSc-ILD.

SIBO and Gut Dysbiosis May Overlap

Although SIBO and colonic dysbiosis are different concepts, they can coexist.

Systemic sclerosis creates several factors capable of disrupting microbial ecology simultaneously:

• reduced intestinal motility

• altered transit time

• proton-pump inhibitor exposure

• antibiotics

• dietary restriction

• malabsorption

• autoimmune inflammation

• disease severity

This makes it difficult to determine which microbial changes are primary and which are secondary.

Could SIBO Increase Systemic Inflammation?

Potentially.

Excessive or abnormal microbial activity may alter exposure to bacterial products and microbial metabolites.

One molecule frequently discussed is lipopolysaccharide, or LPS.

LPS can activate innate immune pathways such as:

TLR4 → NF-κB

which may increase inflammatory cytokines.

Intestinal-barrier dysfunction could theoretically increase systemic exposure to such microbial molecules.

However, direct evidence connecting SIBO-induced endotoxemia with progression of human SSc-ILD remains insufficient.

This is currently a mechanistic hypothesis.

SIBO, SCFAs and Microbial Metabolism

Another potential pathway involves short-chain fatty acids.

SCFAs include:

• acetate

• propionate

• butyrate

These compounds are produced through microbial fermentation.

They can influence:

• intestinal-barrier integrity

• immune regulation

• Treg activity

• inflammatory pathways

SIBO can alter where and how fermentation occurs.

But it would be overly simplistic to say that SIBO merely causes “low butyrate.”

Different microbial communities may produce different metabolic profiles.

The important issue may ultimately be microbial function rather than bacterial quantity alone.

SIBO and Tryptophan Metabolism

Gut microorganisms also metabolize tryptophan into compounds capable of influencing immune signaling.

Some microbial indoles interact with the aryl hydrocarbon receptor, or AhR.

AhR signaling can affect:

• epithelial integrity

• immune tolerance

• Treg/Th17 balance

Abnormal microbial ecology could therefore theoretically alter tryptophan-derived signaling.

This represents another possible gut–immune–lung pathway, but its role specifically in SIBO-associated SSc-ILD has not been established.

The Immune System May Be the Missing Link

Systemic sclerosis involves dysregulated immunity.

The microbiome also regulates immunity.

This overlap makes the gut–lung hypothesis particularly attractive.

Gut microorganisms can interact with:

• regulatory T cells

• Th17 cells

• macrophages

• dendritic cells

• B-cell responses

If dysbiosis or SIBO modifies these pathways, it could potentially influence systemic autoimmune activity.

Whether that translates into measurable changes in pulmonary fibrosis remains an unanswered question.

Reflux May Be More Directly Relevant to the Lung

There is another gastrointestinal issue in systemic sclerosis with a more direct anatomical connection to the lung:

gastroesophageal reflux and microaspiration.

Systemic sclerosis commonly impairs esophageal function.

The lower esophageal sphincter may become weak, and esophageal clearance may become poor.

This can cause severe reflux.

Small amounts of gastric or esophageal contents may then enter the respiratory tract.

This is called microaspiration.

Microaspiration Versus the Gut–Lung Axis

These mechanisms should not be confused.

The gut–lung axis generally refers to:

microbiome → metabolites/immune signals → systemic circulation → lung

Microaspiration involves:

esophagus/stomach → refluxed material → direct entry into the respiratory tract

A patient with systemic sclerosis may potentially have both.

This is why gastrointestinal evaluation in SSc-ILD can be relevant for more than one reason.

Could Reflux Worsen SSc-ILD?

Several studies have found associations between esophageal dysfunction, reflux severity and pulmonary involvement in systemic sclerosis.

Microaspiration provides a biologically plausible mechanism for repetitive epithelial injury.

However, association does not establish that reflux is responsible for all progression of SSc-ILD.

Treating clinically significant reflux remains important for appropriate gastrointestinal indications.

Whether aggressive reflux treatment specifically alters ILD progression remains more complex.

Does Treating SIBO Improve Lung Fibrosis?

At present, there is no convincing evidence that treating SIBO:

• improves FVC

• improves DLCO

• reduces HRCT fibrosis

• prevents progressive pulmonary fibrosis

• reduces the need for antifibrotic therapy

• improves survival from SSc-ILD

Therefore, SIBO treatment should not be presented as treatment for lung fibrosis.

This is an important evidence boundary.

Why Treat SIBO Then?

Because SIBO itself can be clinically significant.

Treatment may be appropriate to address:

• bloating

• diarrhea

• abdominal discomfort

• malabsorption

• nutritional deficiency

• weight loss

Improving gastrointestinal function may also make it easier for patients to maintain adequate nutrition and participate in rehabilitation.

These are meaningful clinical outcomes even without proving an antifibrotic effect.

How Is SIBO Diagnosed?

Breath testing is commonly used.

Patients consume a substrate such as:

• glucose

• lactulose

and breath samples are collected over time.

The test measures gases generated by microbial metabolism, particularly:

• hydrogen

• methane

Interpretation should follow accepted clinical criteria.

No test is perfect.

Breath testing has limitations related to intestinal transit, substrate choice and test methodology.

Hydrogen and Methane Are Not the Same

Patients may have different gas patterns.

Hydrogen-predominant overgrowth is often associated with diarrhea or loose stools.

Methane production is frequently associated with slower transit and constipation.

Strictly speaking, methane overproduction is increasingly referred to as:

intestinal methanogen overgrowth — IMO

because methane is produced by archaea rather than bacteria.

This distinction can matter clinically.

What About Hydrogen Sulfide?

Hydrogen sulfide represents another microbial gas pathway.

It is increasingly recognized in SIBO-related research and may be associated with particular gastrointestinal symptom patterns.

Testing remains less universally available and standardized than conventional hydrogen and methane testing.

Importantly, none of these breath-gas patterns has been validated as a pulmonary-fibrosis biomarker.

How Is SIBO Treated in Systemic Sclerosis?

Treatment is individualized and may involve several components.

Antibiotics are commonly used when clinically indicated.

Depending on the situation, clinicians may also consider:

• improving intestinal motility

• addressing constipation

• correcting nutritional deficiencies

• dietary modification

• treating underlying gastrointestinal dysfunction

Because impaired motility often persists in systemic sclerosis, recurrence is common.

This means SIBO management may require more than a single course of treatment.

Why Motility Matters So Much

If bacterial overgrowth occurs because intestinal contents are not moving properly, eliminating bacteria without improving motility may provide only temporary benefit.

This creates the classic cycle:

dysmotility
→ bacterial overgrowth
→ treatment
→ temporary improvement
→ persistent dysmotility
→ recurrence

Therefore, management should consider the underlying physiology.

What About Prokinetics?

Prokinetic medications may be considered in selected systemic sclerosis patients with documented or clinically significant dysmotility.

The appropriate medication depends on the affected part of the gastrointestinal tract and the patient’s clinical situation.

This should be managed medically rather than through a universal SIBO protocol.

What About Diet?

Diet can help control symptoms in some patients.

However, systemic sclerosis requires particular caution with restrictive diets.

A patient may already be at risk of:

• low body weight

• muscle loss

• malnutrition

• micronutrient deficiencies

Long-term highly restrictive diets can worsen these problems.

A temporary dietary strategy aimed at reducing fermentation may help selected patients with severe symptoms, but nutritional adequacy should remain a priority.

Should Everyone With SSc-ILD Avoid Fermentable Foods?

No.

The presence of ILD does not itself justify a low-FODMAP or other restrictive diet.

Dietary intervention should be driven by:

• gastrointestinal symptoms

• nutritional status

• confirmed or suspected GI pathology

• individual tolerance

The goal should be improving health—not simply feeding or starving particular bacteria.

What About Probiotics?

Probiotics are sometimes suggested for SIBO or systemic sclerosis.

However, the evidence is heterogeneous.

Different strains have different effects, and some patients with severe fermentation symptoms may experience increased bloating.

There is currently no probiotic shown to treat SSc-ILD.

Probiotics should therefore be considered according to the patient’s gastrointestinal indication rather than prescribed as antifibrotic therapy.

Could SIBO Treatment Improve the Microbiome?

Potentially, but the relationship is complicated.

Antibiotics can reduce microbial overgrowth while simultaneously altering microbial diversity.

Diet can change substrate availability.

Prokinetics can change the intestinal environment by improving transit.

Therefore, the goal should not simply be to maximize or minimize bacteria.

The goal is to restore appropriate gastrointestinal physiology and improve symptoms and nutritional health.

Functional and Integrative Medicine Perspective

SIBO provides an excellent example of where functional and conventional medicine can overlap productively.

A comprehensive assessment can ask:

• Does the patient actually have symptoms compatible with SIBO?

• Is intestinal dysmotility present?

• Is reflux significant?

• Is constipation contributing?

• Is the patient losing weight?

• Are there nutritional deficiencies?

• Are medications influencing gut function?

• Is there evidence of malabsorption?

• Is the dietary plan sustainable?

For a patient with SSc-ILD, these questions should sit alongside:

• pulmonary function

• HRCT findings

• oxygenation

• disease progression

• autoimmune activity

• pulmonary hypertension assessment

• appropriate immunomodulatory or antifibrotic treatment

This is what genuinely integrated care looks like.

What We Know

We know that:

• SIBO is common in systemic sclerosis

• gastrointestinal dysmotility is an important driver

• SIBO can cause clinically significant gastrointestinal symptoms and nutritional problems

• systemic sclerosis is associated with intestinal dysbiosis

• recent multinational human research demonstrates distinct gut microbial signatures in SSc-ILD

• some microbial features correlate with radiological ILD extent

What We Do Not Know

We do not know whether:

• SIBO causes SSc-ILD

• SIBO accelerates lung fibrosis

• treating SIBO slows FVC decline

• SIBO eradication alters pulmonary prognosis

• probiotics prevent SSc-ILD

• specific SIBO gas patterns predict lung progression

These remain research questions.

What Should Patients Take Away From This?

If you have systemic sclerosis and significant gastrointestinal symptoms, those symptoms deserve proper assessment.

They should not automatically be dismissed as “just part of scleroderma.”

SIBO, reflux, esophageal dysfunction, dysmotility and nutritional problems may all require attention.

But treating these conditions should not be confused with treating the underlying interstitial lung disease.

Both aspects of health matter.

And they may eventually prove to be more interconnected than we currently understand.

Conclusion

SIBO is common in systemic sclerosis because the disease can profoundly disrupt gastrointestinal motility.

At the same time, emerging human evidence demonstrates that the intestinal microbiome differs in patients with systemic sclerosis-associated ILD.

This creates a compelling gut–lung hypothesis.

SIBO and intestinal dysbiosis could theoretically influence systemic immunity, microbial metabolites, intestinal-barrier function and inflammation.

However, there is currently no evidence that SIBO itself causes SSc-ILD or that treating SIBO slows pulmonary fibrosis.

The clinical message is therefore more nuanced.

SIBO should be identified and treated when clinically appropriate because it can substantially affect gastrointestinal symptoms, nutrition and quality of life.

Meanwhile, SSc-ILD should continue to receive appropriate specialist pulmonary and rheumatological treatment.

Future research must determine whether these two areas eventually intersect therapeutically.

If treating intestinal microbial dysfunction can one day be shown to change pulmonary outcomes, it could add an entirely new dimension to the management of systemic sclerosis.

For now, the gut–lung connection remains an important emerging field—promising enough to investigate seriously, but not yet strong enough to replace established treatment.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical approach combines evidence-based pulmonary medicine with functional and integrative medicine, with particular interest in autoimmune-associated ILD, the gut–lung axis, gastrointestinal health, nutrition and metabolic factors that may influence overall health in people with chronic lung disease.

Living With Systemic Sclerosis and Interstitial Lung Disease?

If you have systemic sclerosis-associated ILD and are also experiencing gastrointestinal problems such as persistent bloating, reflux, altered bowel habits or suspected SIBO, a comprehensive assessment can consider these issues alongside your pulmonary disease rather than treating them as completely separate problems.

To learn more about online consultation options, contact us through the consultation page or WhatsApp.

Functional and integrative care is intended to complement—not replace—appropriate pulmonary, rheumatological, immunomodulatory or antifibrotic treatment.

Medical Disclaimer: This article is for educational purposes and is not a substitute for individualized medical advice. SIBO testing and treatment should be selected according to the patient’s clinical presentation, and patients with SSc-ILD require appropriate specialist follow-up.

Gut Microbiome and Systemic Sclerosis–Associated Interstitial Lung Disease: Is There a Gut–Lung Connection?

Could the Gut Be Connected to Lung Fibrosis in Systemic Sclerosis?

Systemic sclerosis—also known as scleroderma—is a complex autoimmune disease that can affect multiple organs.

Two organ systems are particularly important:

the gastrointestinal tract and the lungs.

Gastrointestinal involvement is extremely common in systemic sclerosis. Patients may experience reflux, difficulty swallowing, delayed intestinal transit, constipation, diarrhea, bloating, malabsorption and small intestinal bacterial overgrowth (SIBO).

At the same time, interstitial lung disease (ILD) is one of the most important pulmonary complications of systemic sclerosis and a major contributor to disease-related morbidity and mortality.

For many years, these problems were largely considered separately.

The gut was the gut.

The lung was the lung.

Microbiome research is beginning to challenge that separation.

Increasing evidence suggests that patients with systemic sclerosis have an altered intestinal microbiome, or gut dysbiosis.

More importantly, new human research suggests that patients who develop systemic sclerosis-associated interstitial lung disease (SSc-ILD) may have intestinal microbial characteristics that differ from those of systemic sclerosis patients without ILD.

This has raised an important question:

Could the gut microbiome influence the development or progression of lung disease in systemic sclerosis?

The answer is not yet established.

But the evidence has become sufficiently compelling that the gut–lung axis is now a serious area of SSc-ILD research.

What Is Systemic Sclerosis–Associated ILD?

Systemic sclerosis is characterized by varying combinations of:

• autoimmunity

• vascular dysfunction

• inflammation

• abnormal fibroblast activation

• tissue fibrosis

Fibrosis can affect the skin and several internal organs.

When the lungs are involved, patients may develop interstitial lung disease.

SSc-ILD can range from relatively mild radiological abnormalities to progressive fibrotic disease causing:

• breathlessness

• exercise limitation

• cough

• impaired gas transfer

• declining lung function

The most common radiological pattern is nonspecific interstitial pneumonia (NSIP), although other patterns can occur.

The clinical course varies substantially between patients.

Some remain stable for years.

Others develop progressive pulmonary fibrosis.

Understanding why these differences occur is one of the major challenges in systemic sclerosis.

The microbiome may represent one piece of that puzzle.

Why Is the Gut Particularly Relevant in Systemic Sclerosis?

Systemic sclerosis is almost uniquely suited to studying the gut–lung axis because gastrointestinal dysfunction is so common.

Fibrosis, vascular abnormalities and autonomic or neuromuscular dysfunction can impair normal gastrointestinal movement.

This may affect:

• the esophagus

• stomach

• small intestine

• colon

Reduced motility changes the intestinal environment.

When intestinal contents remain stagnant for longer periods, microbial populations can change dramatically.

This can contribute to:

dysbiosis and SIBO.

At the same time, changes in diet, acid-suppressing medications, antibiotics and immune-modulating treatments may further modify the microbiome.

Therefore, a patient with systemic sclerosis may have several simultaneous factors capable of disrupting intestinal ecology.

What Is Gut Dysbiosis?

The intestinal microbiome contains trillions of microorganisms and an enormous collection of microbial genes.

These microorganisms help regulate:

• digestion

• vitamin metabolism

• immune development

• intestinal-barrier integrity

• production of microbial metabolites

Dysbiosis refers to disruption of this ecosystem.

It may involve:

• reduced microbial diversity

• depletion of potentially beneficial organisms

• expansion of opportunistic organisms

• altered microbial metabolic activity

• changes in immune–microbiome interactions

Studies have repeatedly demonstrated intestinal dysbiosis in systemic sclerosis.

The more recent question is whether particular patterns of dysbiosis are associated specifically with lung involvement.

The International SSc-ILD Gut Microbiome Study

One of the most important advances in this field came from an international investigation of the gut–lung axis in systemic sclerosis.

Researchers recruited 285 patients with systemic sclerosis from seven specialist centers across five continents.

Approximately 62.5% had interstitial lung disease.

Instead of using relatively limited bacterial sequencing techniques, researchers performed shotgun metagenomic sequencing.

This allowed much more detailed characterization of intestinal microbial species and their functional pathways.

Patients with SSc-ILD demonstrated a distinct intestinal microbial signature compared with systemic sclerosis patients without ILD.

The signature included increased abundance of several candidate pathobionts.

Even more interestingly, among patients with SSc-ILD, particular bacterial species and microbial functional pathways were associated with the radiological extent of ILD on HRCT.

This represents an important shift in the evidence.

The question is no longer simply:

“Do systemic sclerosis patients have dysbiosis?”

We can now ask:

“Are particular intestinal microbial patterns associated with the pulmonary phenotype and severity of systemic sclerosis?”

The answer appears to be yes.

However, association still does not prove causation.

Why Is This Study Important?

Previous microbiome studies in systemic sclerosis often came from relatively small, geographically limited cohorts.

That creates a problem.

The microbiome is strongly influenced by:

• geography

• ethnicity

• habitual diet

• medication

• environment

• lifestyle

A microbial signature identified in one country may not necessarily apply to patients elsewhere.

The multinational nature of the SSc-ILD study therefore makes the finding particularly interesting.

It suggests that relationships between intestinal microbial biology and ILD may persist despite substantial geographic variation.

Still, these findings require further validation.

Does Gut Dysbiosis Cause SSc-ILD?

We cannot currently say that it does.

Several explanations remain possible.

Possibility 1: Dysbiosis contributes to ILD

Altered microorganisms could affect immune regulation and microbial metabolite production, potentially influencing pulmonary inflammation and fibrosis.

Possibility 2: More severe systemic sclerosis causes both

Patients with more extensive systemic disease may develop both gastrointestinal dysfunction and pulmonary fibrosis.

Dysbiosis could therefore be a consequence or marker of disease severity.

Possibility 3: Gastrointestinal dysfunction drives dysbiosis

Impaired intestinal motility may create the environment that produces microbial changes.

Possibility 4: The relationship is bidirectional

This may ultimately be the most realistic model.

Systemic sclerosis damages gastrointestinal function.

GI dysfunction changes the microbiome.

The altered microbiome modifies immune and metabolic signaling.

Those signals may then influence systemic disease—including the lungs.

The cycle could reinforce itself.

How Could the Gut Microbiome Influence SSc-ILD?

Several mechanisms are biologically plausible.

1. Immune Dysregulation

Systemic sclerosis is fundamentally an immune-mediated disease.

Gut microorganisms interact with several immune-cell populations, including:

• regulatory T cells

• Th17 cells

• dendritic cells

• macrophages

• B cells

Microbial signals help determine the balance between immune tolerance and immune activation.

Dysbiosis could therefore contribute to systemic immune dysregulation.

In a genetically susceptible person, this may potentially amplify pathways involved in autoimmunity and fibrosis.

This remains a hypothesis, but it has strong biological plausibility.

2. Microbial Metabolites

The gut microbiome produces biologically active compounds that can enter circulation.

These include:

• short-chain fatty acids

• tryptophan metabolites

• bile-acid metabolites

• microbial peptides

These molecules can influence immune cells far beyond the intestine.

This provides a mechanism through which intestinal organisms could affect pulmonary biology without bacteria themselves traveling to the lungs.

3. Short-Chain Fatty Acids and Butyrate

Certain gut bacteria ferment dietary substrates to produce short-chain fatty acids such as:

• acetate

• propionate

• butyrate

Butyrate supports intestinal epithelial health and can influence immune regulation.

SCFAs can also affect regulatory T cells and inflammatory signaling.

A dysbiotic microbiome that alters SCFA production could therefore potentially modify systemic immune function.

Whether this contributes meaningfully to SSc-ILD progression in humans remains unknown.

4. Intestinal Barrier Dysfunction

The intestinal epithelium normally prevents uncontrolled movement of microbial products into circulation.

If barrier integrity becomes impaired, microbial molecules may gain greater systemic access.

One such molecule is lipopolysaccharide, or LPS.

LPS can activate innate immune pathways such as:

TLR4 → NF-κB

and increase inflammatory cytokine production.

Theoretically, this could contribute to systemic immune activation and profibrotic signaling.

However, direct evidence that increased intestinal permeability drives human SSc-ILD remains insufficient.

5. Fibroblast Activation

Systemic sclerosis is characterized by abnormal fibroblast activity.

Activated fibroblasts and myofibroblasts produce excessive:

• collagen

• fibronectin

• extracellular matrix

TGF-β is one of the central signaling molecules driving this process.

Microbial metabolites and immune signals can influence pathways connected with TGF-β and fibroblast behavior experimentally.

This creates another potential bridge between intestinal biology and fibrosis.

SIBO: An Important Part of the Story

Small intestinal bacterial overgrowth is common in systemic sclerosis.

A previous systematic review estimated that SIBO occurs in approximately 39% of patients with systemic sclerosis, although prevalence varies substantially according to the population and diagnostic method.

Why is SIBO so common?

One major reason is impaired intestinal motility.

Normally, coordinated intestinal contractions help prevent excessive bacterial accumulation in the small intestine.

In systemic sclerosis, motility may be impaired.

This can lead to:

stasis → bacterial overgrowth → fermentation → symptoms and malabsorption

Symptoms may include:

• bloating

• abdominal distension

• diarrhea

• abdominal discomfort

• excessive gas

• nutritional deficiencies

• weight loss

Severe or recurrent SIBO can contribute to malnutrition.

That matters greatly in a patient already coping with chronic lung disease.

Does SIBO Cause SSc-ILD?

This is an important distinction.

SIBO is common in systemic sclerosis.

ILD is also common.

But the coexistence of the two does not prove that SIBO causes pulmonary fibrosis.

Currently, there is insufficient evidence to conclude that treating SIBO slows SSc-ILD progression.

However, identifying and treating clinically significant SIBO may still be important because it can improve gastrointestinal symptoms and nutritional status.

Those benefits matter independently of any hypothetical pulmonary effect.

Reflux May Provide Another Gut–Lung Connection

Systemic sclerosis commonly affects the esophagus.

Patients may develop:

• reduced lower esophageal sphincter pressure

• impaired esophageal clearance

• severe gastroesophageal reflux

• swallowing dysfunction

This creates another potential route connecting the gastrointestinal tract and lungs:

microaspiration.

Small amounts of gastric or esophageal contents may reach the respiratory tract.

This mechanism is different from the systemic microbiome pathway.

The microbiome pathway involves metabolites and immune signals traveling through the body.

Microaspiration involves material physically entering the respiratory tract.

Both may potentially operate in the same patient.

Reflux, Microaspiration and Lung Fibrosis

Microaspiration has long been investigated as a possible contributor to lung injury in systemic sclerosis.

The concept is biologically plausible:

esophageal dysfunction
→ reflux
→ microaspiration
→ repetitive epithelial injury
→ pulmonary inflammation/fibrotic signaling

However, determining the exact contribution of reflux to SSc-ILD progression is difficult.

Nevertheless, severe reflux and swallowing dysfunction are clinically important and deserve appropriate assessment.

SIBO, Reflux and Dysmotility Are Different Problems

These conditions are sometimes incorrectly grouped together as simply “poor gut health.”

They are distinct.

GERD involves reflux of gastric contents.

Esophageal dysmotility involves abnormal movement through the esophagus.

SIBO involves excessive or abnormal microbial populations in the small intestine.

Gut dysbiosis refers more broadly to altered microbial ecology.

A patient can have one without the others.

An integrative assessment should therefore identify the actual gastrointestinal problem rather than applying a generic “gut healing” protocol.

Could Treating the Gut Improve SSc-ILD?

This remains one of the major unanswered questions.

Potential microbiome-directed approaches under investigation include:

• dietary intervention

• probiotics

• prebiotics

• antibiotics

• prokinetics

• fecal microbiota transplantation

• targeted microbial metabolites

But no microbiome-directed intervention has yet been established as a treatment capable of slowing SSc-ILD.

Probiotics in Systemic Sclerosis

Probiotic and synbiotic interventions have been investigated in systemic sclerosis, particularly for gastrointestinal symptoms.

A recent systematic review evaluated probiotics, prebiotics and synbiotics in scleroderma and concluded that evidence remains insufficient and heterogeneous.

Importantly, there are currently no established recommendations supporting these interventions as treatments for SSc-ILD.

This is an important boundary.

A probiotic may potentially help a gastrointestinal symptom in selected patients.

That is different from treating pulmonary fibrosis.

Fecal Microbiota Transplantation

FMT is another emerging area.

The procedure transfers a complex microbial community from a donor into a recipient.

Small experimental studies in systemic sclerosis have explored microbiota transplantation and gastrointestinal outcomes.

The concept is scientifically interesting because FMT changes the microbial ecosystem more substantially than a conventional probiotic.

However, FMT is not established therapy for systemic sclerosis or SSc-ILD.

It should currently be regarded as investigational in this context.

Could the Microbiome Become a Biomarker?

This may actually occur before microbiome therapy becomes available.

The international SSc-ILD study raises the possibility that microbial signatures might eventually help identify:

• patients at risk of ILD

• different disease phenotypes

• patients with more extensive pulmonary disease

• biological pathways associated with progression

But substantial validation is required.

Microbiome profiles are influenced by many confounders, including medications and geography.

Therefore, stool microbiome testing is not currently part of standard SSc-ILD risk stratification.

Should Patients With SSc-ILD Have Commercial Microbiome Testing?

Not routinely for the purpose of managing their lung disease.

Commercial stool testing may provide information about gastrointestinal function in selected circumstances.

But no commercial microbiome test has been validated to:

• diagnose SSc-ILD

• predict progression

• determine HRCT severity

• select immunosuppressive treatment

• select antifibrotic therapy

• determine which probiotic will improve the lung disease

Research metagenomics should not be confused with routine commercial testing.

Nutrition Is Particularly Important in SSc-ILD

Patients with systemic sclerosis can be nutritionally vulnerable.

Potential contributors include:

• dysphagia

• reflux

• gastroparesis

• intestinal dysmotility

• SIBO

• diarrhea

• malabsorption

• reduced appetite

• restrictive diets

Meanwhile, chronic lung disease can increase the importance of maintaining muscle mass and adequate nutrition.

Therefore, dietary interventions should be individualized.

A highly restrictive “microbiome diet” that produces weight loss or protein deficiency may ultimately be harmful.

What About a High-Fiber Diet?

Fiber can support microbial fermentation and SCFA production.

But systemic sclerosis is one of the clearest examples of why generic high-fiber recommendations can fail.

A patient with severe dysmotility or SIBO may experience substantial:

• bloating

• gas

• abdominal pain

• distension

after rapidly increasing fermentable fiber.

The appropriate diet depends on gastrointestinal phenotype and nutritional needs.

Functional Medicine and SSc-ILD

Systemic sclerosis-associated ILD is precisely the type of complex disease where an integrative framework can be useful—provided that evidence and priorities remain clear.

Conventional pulmonary and rheumatological assessment remains essential.

Depending on the patient, established treatment may involve:

• immunomodulatory therapy

• antifibrotic therapy

• pulmonary monitoring

• pulmonary rehabilitation

• oxygen

• transplantation evaluation

An integrative assessment can then examine additional clinically relevant factors such as:

• reflux

• aspiration risk

• dysphagia

• SIBO

• intestinal dysmotility

• nutritional status

• vitamin and mineral deficiencies

• muscle mass

• sleep

• physical activity

• metabolic health

This is very different from claiming that the disease can be treated by “healing the gut.”

What We Know

We now know that:

• intestinal dysbiosis occurs in systemic sclerosis

• SIBO is common

• gastrointestinal dysmotility strongly influences intestinal ecology

• patients with SSc-ILD have distinct intestinal microbial characteristics

• particular microbial species and functional pathways correlate with radiological ILD extent

This represents genuine human evidence for a gut–lung association.

What We Do Not Know

We still do not know whether:

• dysbiosis causes SSc-ILD

• microbial changes precede pulmonary disease

• treating dysbiosis prevents ILD

• treating SIBO slows fibrosis

• probiotics improve lung function

• FMT modifies ILD progression

• microbiome signatures can reliably predict prognosis

These questions require prospective and interventional studies.

What Should Patients With SSc-ILD Do Today?

The practical message is not that every patient needs a microbiome protocol.

Instead, gastrointestinal health deserves appropriate clinical attention.

Symptoms such as:

• persistent bloating

• diarrhea

• constipation

• reflux

• difficulty swallowing

• early satiety

• unexplained weight loss

should not automatically be accepted as unavoidable consequences of systemic sclerosis.

They may warrant evaluation for conditions such as:

• SIBO

• esophageal dysfunction

• gastroparesis

• malabsorption

• nutritional deficiency

Treating these problems may improve quality of life and nutritional status even while we continue investigating their relationship with pulmonary disease.

The Future: From Gut Bacteria to Precision SSc-ILD Medicine

The next generation of research will need to go beyond identifying bacterial species.

Researchers will need to combine:

**metagenomics

• metabolomics

• immune profiling

• HRCT quantification

• pulmonary function

• longitudinal outcomes**

The key question will become:

Do microbial changes occur before lung progression—and can changing those pathways alter the disease?

If the answer is yes, microbiome science could eventually produce new biomarkers or therapeutic targets for SSc-ILD.

The international multicenter findings make that possibility increasingly worthy of investigation.

Conclusion

The relationship between the gut microbiome and systemic sclerosis-associated interstitial lung disease has moved from an interesting theory toward a genuine area of human clinical research.

We now have multinational evidence demonstrating that patients with SSc-ILD possess distinct intestinal microbial characteristics and that specific microbial species and functional pathways are associated with the radiological extent of lung disease.

That is significant.

But it does not yet demonstrate that gut dysbiosis causes pulmonary fibrosis or that correcting the microbiome will slow SSc-ILD.

The most accurate interpretation is that the intestinal microbiome may be one component of a much larger network involving:

gastrointestinal dysmotility + microbial ecology + immune dysregulation + metabolism + autoimmunity + fibrosis.

For patients, gastrointestinal health deserves attention because reflux, dysmotility, SIBO and malnutrition are clinically important problems in their own right.

For researchers, the next challenge is considerably more ambitious:

Can changing the gut environment change what happens in the lungs?

That question may eventually open an entirely new therapeutic direction for autoimmune interstitial lung disease.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension and lung transplantation at the University of Toronto.

Her clinical approach combines specialist pulmonary medicine with evidence-based functional and integrative medicine, with particular interest in the gut–lung axis, autoimmune-associated ILD, nutrition, metabolic health and gastrointestinal factors that may influence chronic lung disease.

Looking for a Comprehensive Approach to Systemic Sclerosis–Associated ILD?

If you are living with systemic sclerosis-associated interstitial lung disease and would like a comprehensive assessment that combines specialist ILD expertise with an evidence-based functional and integrative perspective, you can explore the available consultation options.

The assessment may include consideration of your pulmonary disease alongside relevant factors such as gastrointestinal symptoms, reflux, nutrition, metabolic health, lifestyle and other potentially modifiable contributors to overall health.

Contact us through the consultation page or WhatsApp to learn more about online consultation options.

Functional and integrative care is intended to complement—not replace—appropriate rheumatological, pulmonary, immunomodulatory or antifibrotic treatment.

Medical Disclaimer: This article is for educational purposes and does not constitute individualized medical advice. Patients with systemic sclerosis-associated ILD should remain under appropriate specialist pulmonary and rheumatological care.

Short-Chain Fatty Acids (SCFAs) and Pulmonary Fibrosis: Could Gut Metabolites Influence Lung Fibrosis?

What Do Gut Bacteria Have to Do With Lung Fibrosis?

When researchers discuss the gut–lung axis, one of the most important questions is not simply:

Which bacteria live in the gut?

A potentially more useful question is:

What are those bacteria producing?

The intestinal microbiome functions almost like a large metabolic organ.

Gut microorganisms break down components of food that human digestive enzymes cannot fully process and transform them into biologically active compounds.

Among the most important of these compounds are short-chain fatty acids, or SCFAs.

The three principal SCFAs are:

• acetate

• propionate

• butyrate

These substances are produced largely through bacterial fermentation of dietary carbohydrates, particularly fermentable fibers and resistant starches.

SCFAs are best known for their role in intestinal health.

But their influence does not stop at the intestinal wall.

They can affect immune cells, inflammatory pathways, epithelial barriers and gene expression, creating a plausible mechanism through which the gut microbiome could influence distant organs—including the lungs.

This has generated considerable interest in pulmonary fibrosis.

Recent reviews of the gut–lung axis identify SCFAs as some of the most important microbial metabolites potentially capable of modifying inflammatory and fibrotic pathways. (PubMed⁠)

However, an important distinction must be made from the beginning:

Evidence that SCFAs influence fibrosis biology does not mean that taking an SCFA supplement has been proven to treat pulmonary fibrosis in humans.

Most therapeutic evidence remains preclinical.

What Are Short-Chain Fatty Acids?

Short-chain fatty acids are organic acids produced predominantly in the colon when gut bacteria ferment carbohydrates that escape digestion in the small intestine.

The main SCFAs are:

Acetate

Usually the most abundant SCFA in the colon and circulation.

Propionate

Used partly by the liver and involved in metabolic and immune signaling.

Butyrate

A major energy source for colonocytes and one of the most intensively studied microbiome metabolites in immune regulation and epithelial-barrier health.

These compounds do considerably more than supply calories.

They act as signaling molecules.

SCFAs can interact with receptors such as:

• GPR41

• GPR43

• GPR109A

They can also influence gene expression through mechanisms such as histone deacetylase inhibition, particularly in the case of butyrate.

This allows the gut microbiome to influence human physiology without bacteria themselves needing to leave the intestine.

How Are SCFAs Produced?

Dietary fibers reach the colon, where bacteria ferment them.

Different bacterial communities possess different metabolic capabilities.

For example, some organisms are particularly efficient at producing butyrate, while others generate acetate that may then be used by other microbes through a process called cross-feeding.

Therefore, SCFA production depends on more than simply how much fiber a person eats.

It also depends on:

• microbiome composition

• substrate availability

• intestinal transit

• cross-feeding between organisms

• colonic pH

• medications

• gastrointestinal disease

• dietary patterns

This is one reason microbiome biology cannot be reduced to a simple equation such as:

more fiber = more butyrate = better health.

Human biology is more complex.

Why Are SCFAs Important to the Gut–Lung Axis?

SCFAs may influence pulmonary health through several pathways.

These include:

1. intestinal-barrier integrity

2. systemic immune regulation

3. macrophage behavior

4. Treg and Th17 balance

5. inflammatory signaling

6. epigenetic regulation

7. oxidative stress

8. fibroblast activation

Recent pulmonary-fibrosis literature increasingly focuses on these mechanisms. (PubMed Central (PMC)⁠)

SCFAs and the Intestinal Barrier

The intestinal lining is designed to allow nutrient absorption while preventing uncontrolled movement of microbial products into circulation.

Proteins such as:

• occludin

• claudins

• ZO-1

help maintain tight junctions between intestinal epithelial cells.

SCFAs—particularly butyrate—can support epithelial metabolism and tight-junction integrity.

This may reduce passage of inflammatory microbial molecules into systemic circulation.

Why could that matter to pulmonary fibrosis?

Because greater exposure to microbial products such as lipopolysaccharide, or LPS, may stimulate systemic inflammatory responses capable of influencing the lung.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and Certified Functional Medicine Practitioner, with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

Living with Pulmonary Fibrosis or Interstitial Lung Disease?

If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

صحة الأمعاء والتليف الرئوي: هل توجد علاقة فعلًا؟

هل يمكن أن تؤثر صحة الأمعاء على الرئتين؟

قد يبدو هذا السؤال غريبًا في البداية.

ما علاقة الأمعاء بالرئتين؟

الأمعاء مسؤولة عن الهضم، والرئتان مسؤولتان عن التنفس، فكيف يمكن أن يؤثر أحدهما على الآخر؟

في الحقيقة، بدأ العلم خلال السنوات الأخيرة يكتشف أن أعضاء الجسم لا تعمل بشكل منفصل كما كنا نتصور.

هناك تواصل مستمر بين الأمعاء والرئتين عبر الجهاز المناعي، والدورة الدموية، والمواد التي تنتجها البكتيريا الموجودة في الأمعاء.

وهذا ما يعرف باسم:

محور الأمعاء والرئة – Gut–Lung Axis

وقد أصبح هذا الموضوع محل اهتمام متزايد في أمراض الرئة المزمنة، ومنها التليف الرئوي وأمراض الرئة الخلالية.

لكن من المهم منذ البداية أن نوضح نقطة أساسية:

لا يعني وجود علاقة بين الأمعاء والرئة أن مشاكل الأمعاء هي السبب المباشر للتليف الرئوي، ولا يعني أن علاج الأمعاء وحده يستطيع عكس التليف.

العلم ما زال يتطور.

لكن الأدلة الحالية تشير إلى أن صحة الأمعاء والميكروبيوم قد تكون أحد العوامل التي تؤثر على الالتهاب والمناعة وطريقة استجابة الجسم للمرض.

ما هو ميكروبيوم الأمعاء؟

داخل الأمعاء يعيش عدد هائل من البكتيريا والكائنات الدقيقة.

هذه الكائنات ليست جميعها ضارة.

بالعكس، كثير منها يلعب أدوارًا مهمة جدًا في الجسم، مثل:

• المساعدة في هضم الطعام

• إنتاج بعض الفيتامينات

• دعم جدار الأمعاء

• تنظيم الجهاز المناعي

• إنتاج مواد مفيدة للجسم

• التأثير على الالتهاب

ويطلق على هذا المجتمع الكبير من الكائنات الدقيقة اسم:

ميكروبيوم الأمعاء Gut Microbiome

الميكروبيوم الصحي ليس معناه وجود نوع واحد من “البكتيريا النافعة”.

الأمر أشبه بحديقة متوازنة.

كلما كان هناك تنوع وتوازن بين الأنواع المختلفة، كانت البيئة أكثر استقرارًا.

لكن عندما يحدث اضطراب في هذا التوازن يسمى ذلك:

Gut Dysbiosis – اختلال ميكروبيوم الأمعاء

ماذا يعني اختلال ميكروبيوم الأمعاء؟

اختلال الميكروبيوم قد يعني مثلًا:

• انخفاض تنوع البكتيريا

• نقص بعض الأنواع المفيدة

• زيادة أنواع أخرى قد تسبب الالتهاب

• تغير المواد التي تنتجها البكتيريا

• حدوث تغير في العلاقة بين البكتيريا وجهاز المناعة

وقد تمت دراسة هذا الاضطراب في أمراض كثيرة مثل:

• أمراض المناعة الذاتية

• القولون الالتهابي

• السمنة ومقاومة الإنسولين

• الربو

• أمراض الرئة المزمنة

ومؤخرًا بدأ الباحثون يدرسون علاقته أيضًا بـ التليف الرئوي.

ماذا وجدت الدراسات حتى الآن؟

لفترة طويلة، ركزت الأبحاث على البكتيريا الموجودة داخل الرئة نفسها.

وكان الاعتقاد قديمًا أن الرئة عضو معقم تقريبًا، لكننا نعرف الآن أن الرئة تحتوي أيضًا على مجتمع ميكروبي خاص بها.

وبالفعل وجدت دراسات لدى مرضى التليف الرئوي مجهول السبب IPF تغيرات في كمية وتركيب بعض البكتيريا الموجودة في الجهاز التنفسي.

أما ميكروبيوم الأمعاء فلم تتم دراسته بنفس القوة إلا مؤخرًا.

واليوم بدأت تظهر بيانات بشرية أكثر أهمية.

فقد وجدت دراسات حديثة أن بعض مرضى التليف الرئوي لديهم اختلافات في تركيب بكتيريا الأمعاء مقارنة بالأشخاص الأصحاء.

كما أظهرت دراسة حديثة على أكثر من 400 مريض مصاب بالتليف الرئوي مجهول السبب أن بعض خصائص ميكروبيوم الأمعاء كانت مرتبطة بوظيفة الرئة وشدة المرض.

هذه النتائج مثيرة للاهتمام، لكنها لا تثبت أن تغير البكتيريا هو الذي سبب التليف.

قد يكون تغير الميكروبيوم:

• أحد العوامل التي تساهم في المرض

• أو نتيجة للمرض نفسه

• أو نتيجة للأدوية والنظام الغذائي وقلة الحركة

• أو مزيجًا من كل ذلك

وهذه نقطة مهمة جدًا لفهم الموضوع بشكل صحيح.

كيف يمكن أن تؤثر الأمعاء على الرئتين؟

هناك عدة طرق محتملة.

١. عن طريق الجهاز المناعي

جزء كبير من جهاز المناعة يتفاعل مع الأمعاء بشكل مستمر.

البكتيريا الموجودة داخل الأمعاء تساعد في “تدريب” وتنظيم الجهاز المناعي.

وعندما يحدث اضطراب في الميكروبيوم، قد تتغير طريقة عمل المناعة ويزداد الميل نحو الالتهاب.

وهذا مهم لأن الالتهاب واضطراب المناعة قد يؤثران على الأمراض الرئوية، خصوصًا لدى الأشخاص الذين لديهم أمراض مناعية أو قابلية للإصابة بالتليف.

بمعنى أبسط:

الأمعاء قد لا تسبب التليف مباشرة، لكنها قد تؤثر على البيئة المناعية التي يحدث داخلها المرض.

٢. عن طريق جدار الأمعاء

جدار الأمعاء يعمل كحاجز ذكي.

هو يسمح بامتصاص العناصر الغذائية، لكنه يمنع كثيرًا من المواد غير المرغوبة من الوصول إلى الدم.

عندما يصبح هذا الحاجز أقل كفاءة، قد تزداد نفاذية الأمعاء.

ويستخدم البعض مصطلح:

Leaky Gut – الأمعاء المتسربة

لكن هذا المصطلح أصبح شائعًا جدًا في الإنترنت، وأحيانًا يُستخدم بطريقة مبالغ فيها.

من الناحية العلمية، الأفضل أن نقول:

زيادة نفاذية الأمعاء

إذا زادت هذه النفاذية، قد تعبر بعض المواد التي تنتجها البكتيريا إلى الدورة الدموية وتؤثر على جهاز المناعة والالتهاب في الجسم.

وقد تكون هذه إحدى الطرق التي يمكن من خلالها للأمعاء أن تؤثر بصورة غير مباشرة على الرئة.

لكن حتى الآن لا توجد أدلة تسمح لنا بالقول إن:

Leaky Gut يسبب التليف الرئوي.

٣. عن طريق المواد التي تنتجها بكتيريا الأمعاء

البكتيريا الموجودة في الأمعاء لا تعيش فقط داخلنا، بل تنتج أيضًا مواد تدخل في عمليات مهمة جدًا في الجسم.

من أهم هذه المواد:

الأحماض الدهنية قصيرة السلسلة – SCFAs

ومنها:

• Butyrate – البوتيرات

• Acetate

• Propionate

تنتج هذه المواد عندما تقوم بعض بكتيريا الأمعاء بتخمير الألياف الغذائية.

وهنا تبدأ العلاقة بين:

الطعام → ميكروبيوم الأمعاء → المواد التي تنتجها البكتيريا → جهاز المناعة

وهذه من أهم الأفكار في موضوع Gut–Lung Axis.

ما هو البوتيرات ولماذا يتحدث عنه الباحثون؟

البوتيرات هو أحد أهم المواد التي تنتجها بعض بكتيريا الأمعاء.

وله عدة وظائف مهمة، منها دعم الخلايا التي تبطن القولون والمساعدة في المحافظة على جدار الأمعاء.

كما أن له تأثيرات على الجهاز المناعي والالتهاب.

ولهذا بدأ الباحثون يدرسون ما إذا كان نقص البكتيريا التي تنتج البوتيرات، أو انخفاض إنتاج هذه المواد، يمكن أن يؤثر على أمراض خارج الجهاز الهضمي، ومنها الرئة.

وفي الدراسات التجريبية ظهرت نتائج تشير إلى أن البوتيرات وبعض الـSCFAs قد تؤثر على مسارات مرتبطة بالالتهاب والتليف.

لكن هنا يجب أن نكون واضحين:

وجود فائدة محتملة للبوتيرات في الدراسات المخبرية أو الحيوانية لا يعني أن تناول مكمل Butyrate يعالج التليف الرئوي.

هذا مجال واعد للبحث، لكنه ليس علاجًا مثبتًا حتى الآن.

ماذا عن التربتوفان؟

التربتوفان نوع من الأحماض الأمينية الموجودة في الطعام.

لكن المثير للاهتمام أن بكتيريا الأمعاء تستطيع تحويله إلى مواد مختلفة تؤثر على جهاز المناعة وعلى جدار الأمعاء.

وبدأ الباحثون يدرسون هذه المواد لأنها قد تكون جزءًا من التواصل بين الأمعاء والرئتين.

بعضها قد يساعد على تنظيم الالتهاب والمناعة، وبعضها قد يتغير مع اضطراب الميكروبيوم.

وهذا يجعل Tryptophan Metabolism من المجالات البحثية المهمة في التليف الرئوي.

لكن حتى الآن، لا يوجد علاج معتمد للتليف الرئوي يعتمد على تعديل التربتوفان أو مشتقاته.

هل يمكن للغذاء أن يؤثر على هذه العلاقة؟

نعم، وهذه من أكثر النقاط العملية.

الغذاء أحد أقوى العوامل التي تؤثر على ميكروبيوم الأمعاء.

فالأطعمة التي نتناولها تحدد إلى حد كبير “نوع الغذاء” المتوفر للبكتيريا داخل الأمعاء.

على سبيل المثال، بعض أنواع الألياف والنشويات المقاومة تساعد البكتيريا على إنتاج مواد مثل البوتيرات.

لكن هذا لا يعني أن كل شخص مصاب بالتليف الرئوي يجب أن يتناول كميات كبيرة من الألياف.

فبعض المرضى قد يعانون من:

• انتفاخ شديد

• SIBO

• بطء حركة الأمعاء

• مشاكل في المريء

• ارتجاع معدي شديد

• تصلب الجلد Systemic Sclerosis

وفي هذه الحالات، قد تحتاج الخطة الغذائية إلى تعديل حسب حالة المريض.

لذلك في الطب التكاملي لا توجد قاعدة واحدة تناسب الجميع.

الهدف هو الوصول إلى نظام غذائي يدعم:

• الحالة الغذائية

• الكتلة العضلية

• صحة الأمعاء

• التحكم في الوزن

• الصحة الاستقلابية

• وتقليل المشاكل الهضمية

من دون أن يسبب أعراضًا إضافية.

هل البروبيوتيك مفيد للتليف الرئوي؟

هذا من أكثر الأسئلة التي قد تخطر على بال المريض.

هل تناول البروبيوتيك يساعد على التليف؟

الإجابة حاليًا:

لا نملك دليلًا سريريًا يثبت أن البروبيوتيك يعالج التليف الرئوي أو يوقف تطوره.

هناك دراسات كثيرة تبحث في البروبيوتيك والميكروبيوم وصحة المناعة والرئة.

وهناك نتائج مشجعة في بعض الدراسات الحيوانية وبعض الأمراض الأخرى.

لكن لا يوجد حتى الآن دليل قوي على أن البروبيوتيك:

• يوقف تقدم التليف

• يحسن وظائف الرئة بشكل مثبت

• يقلل الحاجة لزراعة الرئة

• أو يعكس التليف الموجود

لذلك يجب النظر إليه كجزء محتمل من دعم صحة الأمعاء في بعض الحالات، وليس كعلاج بديل للتليف.

ماذا عن FMT أو زراعة ميكروبيوم البراز؟

زراعة ميكروبيوم البراز أو:

Fecal Microbiota Transplantation – FMT

هي طريقة تنقل فيها بكتيريا أمعاء من متبرع إلى شخص آخر بهدف تغيير الميكروبيوم.

وتستخدم حاليًا بصورة مثبتة في حالات محددة جدًا، مثل بعض حالات عدوى C. difficile المتكررة.

أما في التليف الرئوي، فهي لا تزال في مرحلة البحث.

هناك اهتمام كبير بها لأن تغيير الميكروبيوم بشكل واضح قد يساعد العلماء على فهم ما إذا كان للأمعاء دور حقيقي في المرض.

لكن لا يوجد حتى الآن دليل يسمح باستخدام FMT كعلاج للتليف الرئوي.

ماذا عن أمراض الرئة الخلالية المرتبطة بالمناعة؟

هذه من أهم المناطق التي قد تكون فيها العلاقة بين الأمعاء والرئة أكثر وضوحًا.

بعض أمراض المناعة الذاتية قد تسبب أمراضًا رئوية خلالية، مثل:

• تصلب الجلد Systemic Sclerosis

• الروماتويد Rheumatoid Arthritis

• التهاب العضلات المناعي

• متلازمة شوغرن

• Antisynthetase Syndrome

وفي هذه الأمراض، جهاز المناعة نفسه جزء أساسي من المشكلة.

وبما أن ميكروبيوم الأمعاء يؤثر على تنظيم جهاز المناعة، فمن الطبيعي أن يهتم الباحثون بمعرفة ما إذا كان اضطراب الميكروبيوم مرتبطًا أيضًا بتطور إصابة الرئة.

ميكروبيوم الأمعاء وتصلب الجلد

تصلب الجلد Systemic Sclerosis من أكثر الأمثلة إثارة للاهتمام.

فهؤلاء المرضى يعانون كثيرًا من مشاكل في الجهاز الهضمي مثل:

• الارتجاع

• صعوبة البلع

• بطء حركة الأمعاء

• الانتفاخ

• SIBO

كما أن التليف الرئوي من أهم مضاعفات المرض.

وفي دراسة دولية حديثة شملت مئات المرضى، وجد الباحثون أن المرضى المصابين بـSystemic Sclerosis مع ILD لديهم نمط مختلف في بكتيريا الأمعاء مقارنة بالمرضى الذين لم يصابوا بـILD.

كما ارتبطت بعض التغيرات بدرجة إصابة الرئة في الأشعة.

هذه نتائج مهمة لأنها تدعم فكرة وجود علاقة حقيقية بين الأمعاء والمناعة والرئة.

لكنها لا تعني أن علاج الميكروبيوم سيعالج SSc-ILD.

هذا ما تحتاج الدراسات القادمة إلى إثباته.

هل الارتجاع المعدي له علاقة بالتليف الرئوي؟

هذه نقطة مختلفة قليلًا عن Gut–Lung Axis لكنها مهمة جدًا.

الارتجاع المعدي المريئي شائع لدى مرضى IPF وتصلب الجلد.

وفي بعض الحالات يمكن أن تصل كميات صغيرة جدًا من محتويات المعدة إلى الجهاز التنفسي.

وهذا يسمى:

Microaspiration

وقد يؤدي إلى وصول الحمض أو الإنزيمات أو بعض مكونات المعدة إلى الرئة.

لذلك قد يكون لدينا أكثر من طريقة يؤثر بها الجهاز الهضمي على الرئة:

1. عن طريق المناعة والميكروبيوم والمواد التي تنتجها البكتيريا.

2. عن طريق الارتجاع والـmicroaspiration بصورة أكثر مباشرة.

وهما موضوعان مرتبطان، لكنهما ليسا الشيء نفسه.

ماذا يعني الطب الوظيفي والتكاملي في مريض التليف الرئوي؟

الطب الوظيفي والتكاملي لا يعني استبدال أدوية الرئة أو العلاجات المثبتة.

بل يعني النظر إلى المريض بصورة أوسع.

فمثلًا قد يشمل التقييم:

صحة الجهاز الهضمي

مثل:

• الارتجاع

• الانتفاخ

• الإمساك أو الإسهال

• مشاكل حركة الأمعاء

• SIBO عند وجود أعراض مناسبة

التغذية

مثل:

• فقدان الوزن

• نقص البروتين

• فقدان العضلات

• السمنة

• نقص بعض الفيتامينات

• جودة النظام الغذائي

نمط الحياة

مثل:

• النشاط البدني

• التأهيل الرئوي

• النوم

• التدخين

• المحافظة على القوة العضلية

التعرضات البيئية

مثل:

• الطيور

• العفن والرطوبة

• السيليكا

• غبار العمل

• بعض المواد الكيميائية

لكن يجب تقييم هذه الأمور بصورة طبية صحيحة، لأن بعض التعرضات قد تكون فعلًا سببًا لأمراض رئوية مثل Hypersensitivity Pneumonitis، بينما لا ينبغي تفسير كل حالة تليف على أنها “سموم في الجسم”.

هل اختبارات الميكروبيوم مفيدة؟

قد يكون هذا من المواضيع التي يسمع عنها المرضى كثيرًا.

توجد اليوم اختبارات تجارية كثيرة تحلل بكتيريا البراز.

لكن يجب التعامل معها بحذر.

حتى الآن، لا يوجد اختبار ميكروبيوم يستطيع أن يقول:

هذه البكتيريا هي سبب التليف الرئوي لديك.

ولا يوجد اختبار يستطيع أن يحدد بشكل موثوق العلاج المضاد للتليف الذي يحتاجه المريض.

قد تكون هذه الاختبارات مفيدة في بعض الحالات الهضمية، أو لأغراض بحثية، لكن استخدامها في التليف الرئوي لا يزال محدودًا.

ماذا نعرف فعليًا حتى الآن؟

نعرف أن:

• الأمعاء والرئتين تتواصلان عبر المناعة والدورة الدموية.

• ميكروبيوم الأمعاء يؤثر على الالتهاب وتنظيم المناعة.

• بعض مرضى التليف الرئوي لديهم تغيرات في ميكروبيوم الأمعاء.

• هناك دراسات بشرية حديثة تربط بعض خصائص الميكروبيوم بشدة المرض.

• توجد مواد تنتجها البكتيريا مثل البوتيرات قد تؤثر على مسارات مرتبطة بالالتهاب والتليف.

• العلاقة تبدو مهمة بشكل خاص في بعض أمراض المناعة مثل Systemic Sclerosis–ILD.

وماذا لا نعرف؟

لا نعرف حتى الآن بشكل قاطع:

• هل اضطراب الميكروبيوم يسبب التليف أم يحدث بسببه؟

• هل تعديل الميكروبيوم يبطئ تقدم المرض؟

• هل هناك بروبيوتيك محدد مفيد؟

• هل مكمل البوتيرات مفيد؟

• هل FMT مفيد؟

• هل هناك “نظام غذائي مضاد للتليف”؟

ولا توجد حتى الآن أدلة تسمح بالإجابة بنعم عن هذه الأسئلة.

إذن ماذا يعني هذا للمريض؟

الرسالة العملية بسيطة:

صحة الأمعاء مهمة، لكنها ليست بديلًا عن علاج التليف الرئوي.

إذا كان المريض يعاني من مشاكل هضمية، ارتجاع، SIBO، سوء تغذية، فقدان وزن، مشاكل في الامتصاص أو اضطراب في النظام الغذائي، فمن المنطقي تقييم هذه الجوانب ومعالجتها.

كما أن تحسين جودة الغذاء، والحفاظ على الكتلة العضلية، والنشاط البدني، والتأهيل الرئوي، والنوم والصحة الاستقلابية كلها أمور مهمة في الرعاية الشاملة.

لكن يجب أن تستمر هذه الرعاية جنبًا إلى جنب مع:

• العلاج المضاد للتليف عند الحاجة

• العلاج المناعي إذا كان المرض مرتبطًا بالمناعة

• متابعة وظائف الرئة

• الأشعة

• الأكسجين عند الحاجة

• التأهيل الرئوي

• تقييم زراعة الرئة في الحالات المناسبة

الخلاصة

العلاقة بين الأمعاء والرئتين أصبحت من أكثر المجالات إثارة للاهتمام في أبحاث التليف الرئوي.

الميكروبيوم قد يؤثر على جهاز المناعة والالتهاب وسلامة جدار الأمعاء والمواد التي تصل إلى الدورة الدموية.

كما بدأت الدراسات البشرية تظهر اختلافات في ميكروبيوم الأمعاء لدى مرضى التليف الرئوي وبعض أمراض الرئة المناعية.

لكن هذا المجال لا يزال في مرحلة البحث.

والأهم هو عدم تحويل نتائج الدراسات المبكرة إلى وعود علاجية أكبر من الأدلة.

لا يوجد حتى الآن دليل أن علاج الأمعاء وحده يستطيع عكس التليف الرئوي.

لكن من المنطقي أن تكون صحة الأمعاء، والتغذية، والوزن، والعضلات، والنوم، والنشاط البدني، والارتجاع وغيرها من العوامل جزءًا من الرعاية الشاملة للمريض.

وهذا هو جوهر الطب الرئوي التكاملي:

عدم النظر فقط إلى صورة الأشعة أو اختبار وظائف الرئة، بل إلى المريض ككل، مع الحفاظ في الوقت نفسه على العلاج الطبي المبني على الدليل.

تنبيه طبي: هذه المقالة للتثقيف فقط ولا تغني عن استشارة طبيب مختص. التليف الرئوي وأمراض الرئة الخلالية حالات معقدة، ولا ينبغي إيقاف أو تغيير أي دواء بناءً على معلومات تتعلق بالغذاء أو الميكروبيوم دون إشراف طبي

عن د. سمر شاذلي

د. سمر شاذلي هي استشارية أمراض صدرية وطبيبة معتمدة في الطب الوظيفي، مع تدريب وتخصص دقيق في أمراض الرئة الخلالية، التليف الرئوي، ارتفاع ضغط الشريان الرئوي، وزراعة الرئة، إضافة إلى خبرتها في الطب التكاملي والوظيفي.

تركز د. سمر على تقديم نهج يجمع بين طب الرئة المبني على الدليل وبين تقييم العوامل الأخرى التي قد تؤثر على صحة المريض، مثل التغذية، صحة الجهاز الهضمي، الميكروبيوم، الصحة الاستقلابية، نمط الحياة، والتعرضات البيئية.

اهتمامها بشكل خاص هو تطوير مفهوم الطب الرئوي التكاملي والوظيفي Integrative & Functional Pulmonology، خاصة في حالات التليف الرئوي وأمراض الرئة الخلالية المرتبطة بالمناعة، مع الحرص على التمييز بين ما تدعمه الأدلة العلمية حاليًا وما لا يزال في مرحلة البحث.

هل تعاني من التليف الرئوي أو أحد أمراض الرئة الخلالية؟

إذا كنت تبحث عن تقييم أكثر شمولًا لحالتك يجمع بين خبرة طب الرئة التقليدي والمنظور التكاملي والوظيفي، يمكنك التواصل معنا لمعرفة ما إذا كان هذا النوع من الاستشارة مناسبًا لحالتك.

للاطلاع على خيارات الاستشارة أو طلب تقييم، تواصل معنا عبر صفحة الحجز أو الواتساب.

الاستشارة التكاملية لا تستبدل العلاج الرئوي المعياري، وإنما تهدف إلى استكماله ضمن خطة فردية مبنية على التشخيص والأدلة العلمية.

Gut–Lung Axis and Pulmonary Fibrosis: Can Gut Health Affect Lung Fibrosis?

Can the Health of Your Gut Affect Your Lungs?

At first glance, the intestine and lungs appear to be completely separate organs. One processes food and houses trillions of microorganisms; the other exchanges oxygen and carbon dioxide.

Yet these two organs are biologically connected.

Researchers increasingly use the term gut–lung axis to describe the bidirectional communication between the gastrointestinal tract, its microbiome, the immune system, microbial metabolites, and the respiratory system.

This emerging field has become particularly interesting in chronic inflammatory lung diseases and, more recently, in interstitial lung disease (ILD) and pulmonary fibrosis.

Pulmonary fibrosis is characterized by abnormal repair of injured lung tissue, activation of fibroblasts and myofibroblasts, excessive extracellular-matrix deposition, and progressive architectural distortion of the lung. In idiopathic pulmonary fibrosis (IPF), this process can lead to progressive loss of lung function.

Traditional models of pulmonary fibrosis have focused primarily on what happens inside the lung. That remains essential. However, newer research raises an additional question:

Could biological signals originating in the gut influence inflammation, immune regulation, epithelial injury, or fibrotic signaling in the lung?

The answer is increasingly intriguing—but it requires scientific caution.

Current evidence supports an association between the intestinal microbiome and pulmonary fibrosis, and experimental studies provide several plausible mechanisms linking the two. Importantly, recent human data have strengthened this association. However, we do not yet have sufficient evidence to conclude that correcting gut dysbiosis can prevent, stop, or reverse pulmonary fibrosis.

Understanding that distinction is central to an evidence-based functional and integrative approach.

What Is the Gut–Lung Axis?

The gut–lung axis is a bidirectional communication network between the gastrointestinal tract and the respiratory system.

Communication can occur through several interconnected pathways:

• the immune system

• microbial metabolites

• systemic circulation

• intestinal and pulmonary barrier function

• inflammatory mediators

• neuroendocrine signaling

• migration or translocation of microbial products

• interactions with the bone marrow and immune-cell production

The intestine contains one of the largest microbial ecosystems in the human body. Collectively, these microorganisms and their genetic material are referred to as the gut microbiome.

Gut bacteria metabolize dietary components—particularly fiber, amino acids, and other substrates—and produce biologically active molecules.

These include:

• short-chain fatty acids such as butyrate, acetate, and propionate

• tryptophan-derived metabolites

• secondary bile acids

• microbial cell-wall products such as lipopolysaccharide (LPS)

• other signaling molecules capable of influencing immune and metabolic pathways

Some of these molecules can enter the circulation and potentially influence distant organs, including the lungs.

The relationship also works in the opposite direction. Lung disease, systemic inflammation, medications, antibiotics, altered diet, reduced physical activity, hypoxemia, and other physiological stresses may influence the intestinal environment.

This is why the concept is called an axis rather than a one-way pathway.

What Is Gut Dysbiosis?

A healthy microbiome is not defined by the presence of one particular “good bacterium.” It is a complex ecological community.

Gut dysbiosis broadly refers to an alteration in the composition or function of this microbial ecosystem.

It may involve:

• loss of microbial diversity

• depletion of potentially beneficial organisms

• expansion of potentially harmful or pro-inflammatory organisms

• changes in microbial metabolic activity

• disruption of normal host–microbe interactions

Dysbiosis has been studied extensively in inflammatory bowel disease, metabolic disease, autoimmune disorders, asthma, COPD, and several other conditions.

Pulmonary fibrosis is now being added to this research landscape.

What Does the Human Evidence Show?

This is where the field has recently become much more interesting.

Earlier pulmonary-fibrosis microbiome research focused heavily on the lung microbiome. Studies demonstrated that the lungs are not sterile and that alterations in pulmonary microbial burden and composition can occur in IPF.

The gut microbiome was much less well studied.

That is changing.

A 2024 study comparing stool microbiota from patients with IPF and healthy controls identified differences in multiple bacterial groups. The study was small, so its findings should be regarded as exploratory rather than definitive. (pubmed.ncbi.nlm.nih.gov⁠)

More importantly, a much larger recent analysis evaluated gut microbiota in 411 participants with IPF from the CleanUP-IPF trial.

Researchers found that gut microbial diversity and community composition were associated with impaired gas exchange as measured by DLCO. Certain bacterial genera were also associated with transplant-free survival, and microbiome characteristics appeared to interact with antimicrobial and antifibrotic treatment exposure.

This does not prove that the gut microbiome causes IPF progression. But it provides substantial human evidence that the intestinal microbial ecosystem is associated with clinically meaningful characteristics of IPF. (pubmed.ncbi.nlm.nih.gov⁠)

This distinction matters:

Association is not causation.

A different microbiome in advanced pulmonary fibrosis could be a contributor to disease, a consequence of disease, or both.

How Could Gut Dysbiosis Influence Pulmonary Fibrosis?

Current research proposes several interconnected mechanisms.

1. Immune Dysregulation

The intestine is one of the body’s largest immune interfaces.

Gut microorganisms continuously interact with intestinal epithelial cells, macrophages, dendritic cells, regulatory T cells, Th17 cells, innate lymphoid cells, and many other components of mucosal immunity.

Changes in gut microbial composition may therefore alter systemic immune signaling.

This becomes relevant to pulmonary fibrosis because abnormal immune activation and inflammatory signaling can interact with epithelial injury and fibroblast activation.

The microbiome may potentially influence the balance between pro-inflammatory and regulatory immune responses, thereby changing the environment in which fibrotic signaling occurs.

Recent mechanistic reviews identify immune dysregulation as one of the principal pathways potentially connecting intestinal dysbiosis with pulmonary fibrosis. (pmc.ncbi.nlm.nih.gov⁠)

2. Intestinal Barrier Dysfunction: The “Leaky Gut” Question

The intestinal lining forms a sophisticated biological barrier.

Its role is not simply to prevent substances from entering the bloodstream. It selectively regulates the interaction between nutrients, microorganisms, microbial molecules, immune cells, and systemic circulation.

When this barrier becomes dysfunctional, intestinal permeability may increase.

The popular term “leaky gut” refers broadly to this phenomenon, although the term is frequently oversimplified in wellness marketing.

Increased permeability may allow greater systemic exposure to microbial components such as LPS.

These signals can potentially promote:

• systemic inflammation

• innate immune activation

• oxidative stress

• cytokine production

All of these processes could theoretically influence a susceptible lung.

However, there is currently insufficient clinical evidence to claim that “leaky gut causes pulmonary fibrosis.”

A more scientifically accurate statement is:

Intestinal barrier dysfunction is a plausible component of gut–lung signaling and is being investigated as a potential contributor to inflammatory and fibrotic pathways.

(pmc.ncbi.nlm.nih.gov⁠)

3. Short-Chain Fatty Acids: Butyrate, Acetate and Propionate

One of the most fascinating links between diet, microbiome, immunity, and the lungs involves short-chain fatty acids (SCFAs).

The principal SCFAs include:

• acetate

• propionate

• butyrate

They are produced primarily when intestinal bacteria ferment dietary fibers and resistant starches.

Butyrate is particularly important for intestinal health because it serves as an energy source for colonocytes and contributes to intestinal barrier integrity.

SCFAs can also exert systemic immunological effects.

Their mechanisms include:

• activation of G-protein-coupled receptors

• regulation of immune-cell differentiation

• modulation of inflammatory signaling

• histone deacetylase inhibition

• effects on epithelial barrier function

These mechanisms have generated interest in whether reduced production of beneficial microbial metabolites could contribute to a systemic environment favoring inflammation or fibrosis.

Experimental pulmonary-fibrosis studies suggest that SCFA-related pathways may influence fibroblast activation and collagen deposition.

But there is a crucial clinical limitation:

Evidence that SCFAs influence fibrotic biology is not equivalent to evidence that taking butyrate supplements treats pulmonary fibrosis.

At present, butyrate should be considered an important research pathway, not an established antifibrotic treatment. (pubmed.ncbi.nlm.nih.gov⁠)

4. Tryptophan Metabolism and the Lung

Tryptophan provides another example of how the gut microbiome may communicate with distant organs.

Intestinal microorganisms transform dietary tryptophan into multiple bioactive compounds.

Some microbial tryptophan metabolites interact with the aryl hydrocarbon receptor (AhR), an important regulator of mucosal immunity and epithelial homeostasis.

Tryptophan metabolism can influence:

• immune tolerance

• epithelial integrity

• inflammatory signaling

• oxidative stress

• immune-cell behavior

Emerging research suggests that disruption of these pathways may be relevant to chronic lung inflammation and potentially pulmonary fibrosis.

However, this remains predominantly a mechanistic and experimental field rather than a validated therapeutic strategy.

(pmc.ncbi.nlm.nih.gov⁠)

5. Bile Acids and Microbial Signaling

Bile acids are often thought of simply as substances required for fat digestion.

Biologically, they are much more than that.

Gut bacteria transform primary bile acids into secondary bile acids, creating signaling molecules capable of interacting with metabolic and immune receptors.

Altered bile-acid metabolism may influence:

• inflammatory pathways

• oxidative stress

• immune regulation

• epithelial function

Recent pulmonary-fibrosis literature identifies altered bile-acid metabolites as another possible connection between gut dysbiosis and fibrotic signaling.

This remains an emerging area of investigation. (pmc.ncbi.nlm.nih.gov⁠)

6. Autophagy, Cellular Stress and Fibrosis

Autophagy is the cellular recycling system responsible for removing damaged proteins and organelles and maintaining cellular homeostasis.

Impaired autophagy has been implicated in pulmonary fibrosis.

Microbial metabolites may influence signaling pathways involved in autophagy, including pathways related to PI3K/AKT/mTOR.

This provides another possible mechanistic bridge between microbial metabolism and fibrotic cellular behavior.

Again, the science is biologically compelling, but translation into human treatment remains incomplete. (pmc.ncbi.nlm.nih.gov⁠)

7. Alveolar Epithelial Injury and Fibroblast Activation

Modern understanding of IPF places repeated alveolar epithelial injury and abnormal repair near the center of disease pathogenesis.

When alveolar epithelial cells are injured, multiple signals can activate fibroblasts.

Fibroblasts can differentiate into myofibroblasts, producing collagen and other extracellular-matrix components.

The gut microbiome is unlikely to be the sole driver of this process.

Instead, current models suggest that microbial signals could potentially modify the biological environment surrounding fibrosis by influencing:

• inflammation

• immune activation

• oxidative stress

• epithelial integrity

• autophagy

• profibrotic signaling

This distinction is important.

Pulmonary fibrosis should not be reduced to a “gut disease.”

The gut–lung axis is better viewed as one potential modifier within a complex fibrotic network.

The Gut–Lung Axis May Be Particularly Important in Autoimmune ILD

One of the most clinically interesting areas of gut–lung research involves connective-tissue-disease-associated interstitial lung disease (CTD-ILD).

This includes ILD associated with:

• systemic sclerosis

• rheumatoid arthritis

• inflammatory myopathies

• Sjögren’s disease

• mixed connective tissue disease

• antisynthetase syndrome

Why might the gut be particularly relevant here?

Because the microbiome is already implicated in the regulation of systemic immunity and autoimmunity.

The question therefore becomes whether intestinal dysbiosis could contribute simultaneously to systemic immune dysregulation and pulmonary manifestations.

We do not yet know the complete answer, but systemic sclerosis provides particularly compelling emerging evidence.

Systemic Sclerosis–Associated ILD: Important New Evidence

Systemic sclerosis is especially relevant to the gut–lung axis because gastrointestinal involvement is extremely common.

Patients may experience:

• esophageal dysmotility

• gastroesophageal reflux

• altered intestinal motility

• small intestinal bacterial overgrowth (SIBO)

• intestinal dysbiosis

At the same time, ILD is one of the most important pulmonary complications of systemic sclerosis.

A major international study recently examined stool microbiota in 285 patients with systemic sclerosis across seven centers on five continents.

Approximately 62.5% had ILD.

Patients with SSc-ILD demonstrated a distinct intestinal microbial signature compared with patients without ILD. Importantly, specific bacterial species and microbial functional pathways were associated with the radiologic extent of ILD.

This represents an important step beyond purely experimental evidence.

It suggests that the intestinal microbiome may potentially relate not only to systemic sclerosis but specifically to its pulmonary phenotype.

Nevertheless, intervention trials are still needed before microbiome manipulation can be recommended as treatment for SSc-ILD. (pubmed.ncbi.nlm.nih.gov⁠)

What About the Lung Microbiome?

The gut microbiome should not be considered in isolation.

The lungs themselves contain microbial communities.

Research in IPF has identified changes in pulmonary bacterial burden and composition, and the lung microbiome may interact directly with local pulmonary immunity.

There may therefore be several interconnected microbial axes:

Gut → immune system → lung

Oral cavity → microaspiration → lung

Lung microbiome → local immunity → epithelial injury

The emerging model is therefore not simply a gut–lung axis but a complex gut–oral–lung microbial network.

Current ILD literature recognizes these interactions but also emphasizes that the gut and oral components require considerably more research. (pubmed.ncbi.nlm.nih.gov⁠)

GERD, Microaspiration and the Gut–Lung Connection

Gastroesophageal reflux disease is common in patients with pulmonary fibrosis, particularly IPF and systemic sclerosis.

Reflux may potentially influence the lungs through a different mechanism from the classical gut–lung axis: microaspiration.

Small amounts of gastric or esophageal contents may reach the respiratory tract, exposing the lung to acid, bile acids, digestive enzymes, microorganisms, and other substances.

This creates an important distinction:

Gut–lung axis: systemic communication through immunity, microbial metabolites and barrier signaling.

Reflux–lung/oral–lung pathways: more direct exposure through aspiration into the respiratory tract.

Both may be relevant, but they should not be confused.

Can Diet Influence the Gut–Lung Axis?

Potentially, yes.

Diet is one of the strongest environmental influences on the intestinal microbiome.

A diet rich in diverse plant fibers can provide substrates for microbial fermentation and SCFA production.

From an integrative-medicine perspective, nutritional assessment may therefore be relevant in patients with chronic lung disease—not because a particular diet has been proven to reverse fibrosis, but because nutrition affects:

• microbiome composition

• metabolic health

• muscle mass

• immune function

• gastrointestinal symptoms

• body weight

• overall resilience during chronic disease

An individualized nutritional strategy may include adequate protein, diverse whole foods where tolerated, fiber appropriate to gastrointestinal tolerance, healthy fats, and correction of documented nutritional deficiencies.

However, patients with advanced ILD, significant weight loss, SIBO, severe reflux, dysmotility, or systemic sclerosis may require individualized dietary modification.

Simply telling every patient to “eat more fiber” is not appropriate.

Do Probiotics Treat Pulmonary Fibrosis?

Currently, no clinical evidence establishes probiotics as a treatment for pulmonary fibrosis.

This is an important distinction because experimental microbiome research can easily be overinterpreted.

Probiotics, prebiotics, dietary modification and fecal microbiota transplantation have produced interesting results in experimental models and other disease contexts.

But we do not yet have sufficient human randomized clinical trials demonstrating that these interventions slow FVC decline, improve survival, prevent progression, or reverse established pulmonary fibrosis.

Therefore, they should not replace:

• antifibrotic therapy when indicated

• immunomodulatory therapy for appropriate autoimmune ILD

• oxygen therapy when required

• pulmonary rehabilitation

• vaccination

• reflux management when clinically indicated

• lung-transplant evaluation when appropriate

• established multidisciplinary ILD care

(pmc.ncbi.nlm.nih.gov⁠)

What About Fecal Microbiota Transplantation?

FMT is another intriguing area of research.

It can dramatically alter the intestinal microbial ecosystem and is an established treatment in selected settings such as recurrent Clostridioides difficile infection.

Its role in pulmonary fibrosis, however, remains experimental.

Animal studies and mechanistic research have generated interest in whether microbiome restoration could alter inflammatory or fibrotic signaling.

That does not mean FMT should currently be performed to treat pulmonary fibrosis.

Important unanswered questions include:

• Which patients might benefit?

• Which microbial signatures are actually harmful?

• Which organisms or metabolites are protective?

• What is the appropriate donor profile?

• How durable are microbiome changes?

• Could microbiome manipulation cause unintended immune or infectious consequences?

Until these questions are addressed in controlled human studies, FMT for pulmonary fibrosis remains investigational. (pubmed.ncbi.nlm.nih.gov⁠)

A Functional and Integrative Medicine Approach to Pulmonary Fibrosis

Functional and integrative medicine can contribute to pulmonary-fibrosis care when it is used to expand comprehensive patient assessment—not replace evidence-based pulmonary medicine.

An integrative evaluation may consider several domains.

1. The pulmonary diagnosis

The first priority remains determining the correct ILD phenotype and cause.

IPF, hypersensitivity pneumonitis, systemic sclerosis-associated ILD, rheumatoid arthritis-associated ILD, myositis-associated ILD and other fibrotic lung diseases are biologically different diseases.

They should not be treated as one entity simply because fibrosis is present.

2. Gastrointestinal health

Depending on symptoms and underlying disease, assessment may include:

• reflux

• dysphagia

• esophageal dysmotility

• constipation or diarrhea

• bloating

• SIBO risk

• medication effects

• nutritional intake

3. Nutrition and metabolic health

Evaluation should consider:

• unintended weight loss

• obesity

• muscle loss

• protein intake

• micronutrient deficiencies

• metabolic disease

• dietary quality

4. Environmental exposures

A careful history may identify clinically relevant exposures such as:

• mold and damp environments

• birds

• occupational dusts

• silica

• metal or wood dust

• farming exposures

• medications

• smoking

Importantly, these exposures must be evaluated using established pulmonary frameworks rather than automatically attributing disease to nonspecific “toxins.”

5. Lifestyle and physiological reserve

Physical activity, pulmonary rehabilitation, sleep, psychological stress, skeletal-muscle preservation, vaccination and smoking cessation can all influence overall health and resilience.

6. Microbiome-related factors

The gut microbiome is an emerging area worth considering scientifically, particularly in patients with significant gastrointestinal disease or autoimmune ILD.

But current commercial stool microbiome testing should not be interpreted as if it can identify the cause of pulmonary fibrosis or dictate an established antifibrotic treatment.

That level of evidence does not yet exist.

What We Know, What We Don’t Know, and What This Means Clinically

What We Know

The gut and lungs communicate through immune, metabolic and microbial pathways.

Patients with pulmonary fibrosis can exhibit alterations in gut and lung microbial communities.

Recent human IPF data demonstrate associations between gut microbial characteristics, disease severity and transplant-free survival. (pubmed.ncbi.nlm.nih.gov⁠)

A large multinational SSc study has also identified intestinal microbial signatures associated with the presence and radiologic severity of SSc-ILD. (pubmed.ncbi.nlm.nih.gov⁠)

SCFAs, tryptophan metabolites, bile acids, LPS and other microbial products provide biologically plausible mechanisms through which the gut microbiome could influence systemic and pulmonary biology. (pmc.ncbi.nlm.nih.gov⁠)

What We Don’t Know

We do not yet know whether gut dysbiosis is a cause, consequence, disease modifier—or some combination of these in pulmonary fibrosis.

We do not have a validated “pulmonary fibrosis microbiome signature” that can currently be used routinely in clinical practice.

We do not have evidence that probiotics, prebiotics, butyrate, FMT or other microbiome-targeted therapies can reverse established pulmonary fibrosis.

And we do not yet know which patients, if any, are most likely to benefit from microbiome-directed treatment.

What This Means Clinically

The gut–lung axis represents an important emerging dimension of pulmonary-fibrosis research.

It should neither be dismissed nor overpromoted.

For patients, the practical message is that optimizing gastrointestinal health, nutritional status, metabolic health and lifestyle can form part of comprehensive care—but these strategies should complement rather than replace established ILD treatment.

For clinicians and researchers, the gut microbiome represents a potentially important source of biomarkers, mechanistic insights and future therapeutic targets.

The Future: Precision Medicine for the Gut–Lung Axis

The future of this field will probably extend far beyond asking whether a patient has “good” or “bad” bacteria.

Research is moving toward integrated multi-omics approaches combining:

• metagenomics

• metabolomics

• transcriptomics

• immune profiling

• host genetics

• clinical phenotyping

The clinically important question may ultimately be not:

“Which bacteria are present?”

but rather:

“What are these microorganisms doing, which metabolites are they producing, how is the host responding, and does that biological pathway modify the patient’s specific form of ILD?”

That is a much more sophisticated model of personalized medicine.

Recent reviews emphasize the need for longitudinal cohorts, mechanistic validation, multi-omics studies and carefully designed human intervention trials before gut-targeted treatments can become part of routine pulmonary-fibrosis management. (pubmed.ncbi.nlm.nih.gov⁠)

Conclusion: Can Gut Health Affect Pulmonary Fibrosis?

The emerging answer is:

Possibly—but the relationship is complex, and the science is still developing.

The intestine and lungs communicate through immune pathways, microbial metabolites, systemic circulation and epithelial barriers. Gut dysbiosis has now been documented in patients with pulmonary fibrosis, while newer human studies demonstrate associations between gut microbiome characteristics and clinically important features of IPF and systemic sclerosis-associated ILD.

SCFAs such as butyrate, tryptophan metabolites, bile acids, LPS and other microbial products provide plausible biological mechanisms connecting intestinal ecology with pulmonary immunity and fibrotic signaling.

About Dr. Samar Shadly

Dr. Samar Shadly is a Consultant Pulmonologist and certified functional medicine practitioner with advanced subspecialty training in interstitial lung disease, pulmonary fibrosis, pulmonary hypertension, and lung transplantation, together with expertise in functional and integrative medicine.

Her approach combines evidence-based pulmonary medicine with a broader assessment of factors that may influence a patient’s overall health, including nutrition, gastrointestinal health, the gut microbiome, metabolic health, lifestyle, and relevant environmental exposures.

A particular focus of her work is the emerging field of Integrative and Functional Pulmonology, especially in pulmonary fibrosis and autoimmune-associated interstitial lung disease. Her goal is to bridge conventional respiratory medicine with scientifically grounded integrative strategies, while clearly distinguishing established clinical evidence from promising but still experimental research.

Living with Pulmonary Fibrosis or Interstitial Lung Disease?

If you are looking for a more comprehensive assessment that combines specialist pulmonary expertise with a functional and integrative perspective, you can explore whether this approach may be appropriate for your individual condition.

To learn more about consultation options or request an assessment, contact us through the consultation page or WhatsApp.

Integrative care is intended to complement—not replace—evidence-based pulmonary treatment and should always be individualized according to the diagnosis and clinical situation.

Why Am I Always Tired? Hidden Causes of Chronic Fatigue

Feeling tired occasionally is normal, especially after a long day or poor sleep. However, many people today experience persistent fatigue, even when they sleep enough and try to maintain a healthy lifestyle.

Chronic fatigue can significantly affect quality of life, productivity, and overall wellbeing. It may cause difficulty concentrating, low motivation, and decreased physical performance.

While many people assume that fatigue is simply the result of stress or lack of sleep, in many cases there are deeper underlying causes.

Understanding the potential root causes of fatigue is an important step toward restoring energy and improving health.

Below are some of the most common hidden causes of chronic fatigue.

1. Blood Sugar Imbalance

One of the most common causes of persistent fatigue is blood sugar instability.

When we consume large amounts of refined carbohydrates or sugary foods, blood sugar rises rapidly. The body responds by releasing insulin to bring blood sugar levels down.

This process can lead to blood sugar spikes followed by crashes, which often cause symptoms such as:

• fatigue
• dizziness
• irritability
• cravings for sugar or carbohydrates
• poor concentration

Over time, repeated blood sugar spikes may contribute to insulin resistance, a condition strongly associated with fatigue and metabolic problems.

2. Nutrient Deficiencies

Your body requires several vitamins and minerals to produce energy at the cellular level.

Deficiencies in certain nutrients may impair energy production and lead to persistent fatigue.

Common deficiencies associated with fatigue include:

• iron
• vitamin B12
• vitamin D
• magnesium
• folate

Iron deficiency, for example, can lead to anemia, which reduces the oxygen-carrying capacity of the blood and may result in significant fatigue.

3. Thyroid Dysfunction

The thyroid gland regulates metabolism and energy production throughout the body.

When thyroid function is impaired, energy levels can drop significantly.

Hypothyroidism, or underactive thyroid, is commonly associated with symptoms such as:

• fatigue
• weight gain
• cold intolerance
• dry skin
• slow thinking or brain fog

One of the most common causes of hypothyroidism is Hashimoto’s thyroiditis, an autoimmune condition that affects the thyroid gland.

4. Poor Gut Health

The gut plays a crucial role in digestion, nutrient absorption, and immune regulation.

When the gut microbiome becomes imbalanced—a condition known as gut dysbiosis—several symptoms may develop, including fatigue.

Gut health issues associated with fatigue include:

• SIBO (small intestinal bacterial overgrowth)
• Candida overgrowth
• food sensitivities
• intestinal inflammation

Because the gut is responsible for absorbing nutrients, digestive problems may lead to nutrient deficiencies that contribute to fatigue.

5. Chronic Stress

Chronic stress can significantly affect the body's hormonal balance.

Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, leading to increased production of the stress hormone cortisol.

Over time, prolonged stress may disrupt the body's ability to regulate cortisol levels properly.

This imbalance may lead to symptoms such as:

• fatigue
• sleep disturbances
• brain fog
• decreased resilience to stress

6. Poor Sleep Quality

Sleep is essential for restoring energy, repairing tissues, and regulating hormones.

Even if someone sleeps for many hours, poor sleep quality may still result in fatigue.

Common sleep issues include:

• sleep apnea
• insomnia
• irregular sleep schedules
• excessive screen exposure before bedtime

Improving sleep hygiene is often an important step in addressing chronic fatigue.

7. Chronic Inflammation

Low-grade chronic inflammation has been associated with fatigue and reduced energy production.

Inflammation may be triggered by factors such as:

• obesity
• autoimmune diseases
• infections
• environmental toxins
• poor diet

Inflammation can interfere with mitochondrial function, which is responsible for producing energy in the body.

8. Environmental Toxins

Environmental exposures are receiving increasing attention in modern health research.

Certain toxins may affect cellular energy production and neurological function.

Examples include:

• mold toxins (mycotoxins)
• heavy metals
• environmental chemicals
• air pollution

These exposures may contribute to fatigue in susceptible individuals.

9. Lack of Physical Activity

Although it may seem counterintuitive, physical inactivity can actually increase fatigue.

Regular movement improves circulation, supports mitochondrial function, and enhances overall energy metabolism.

Even moderate activity such as walking can help improve energy levels over time.

10. Underlying Medical Conditions

In some cases, persistent fatigue may be related to medical conditions such as:

• anemia
• depression
• chronic infections
• autoimmune diseases
• metabolic disorders

A comprehensive medical evaluation may be necessary to identify the underlying cause.

Chronic Fatigue in Modern Life

Fatigue has become increasingly common in modern society.

Factors such as sedentary lifestyles, processed diets, chronic stress, and environmental exposures may contribute to widespread energy problems.

Addressing fatigue requires looking beyond surface symptoms and identifying the underlying contributors.

Functional Medicine Perspective

Functional medicine focuses on identifying root causes of symptoms rather than simply treating them.

When evaluating chronic fatigue, practitioners may examine several factors including:

• metabolic health
• gut microbiome balance
• hormonal function
• nutrient status
• environmental exposures
• lifestyle factors

By addressing these underlying imbalances, it may be possible to restore energy and improve overall wellbeing.

How to Improve Energy Levels Naturally

Several lifestyle strategies may help support healthy energy levels.

Balanced Nutrition

A diet rich in whole foods, healthy fats, fiber, and protein can help stabilize blood sugar levels and support energy metabolism.

Gut Health Support

Supporting gut microbiome balance through fiber-rich foods and fermented foods may improve digestion and nutrient absorption.

Sleep Optimization

Maintaining consistent sleep schedules and reducing nighttime screen exposure can improve sleep quality.

Stress Management

Practices such as meditation, breathing exercises, and physical activity may help regulate stress hormones.

Physical Activity

Regular exercise supports mitochondrial health, circulation, and metabolic function.

Conclusion

Chronic fatigue is a complex symptom that may have multiple underlying causes.

Rather than ignoring persistent fatigue, it is important to explore potential factors such as blood sugar imbalance, nutrient deficiencies, thyroid dysfunction, gut health issues, stress, and environmental exposures.

By identifying and addressing the root causes of fatigue, individuals may be able to restore energy, improve wellbeing, and support long-term health.

If you are experiencing persistent fatigue and would like a comprehensive evaluation using a functional medicine approach:

Dr. Samar Shadly, MD, IFMCP
د. سمر شاذلي، طبيبة معتمدة في الطب الوظيفي

Website
https://www.drsamarshadly.com

WhatsApp
https://wa.me/966558837786

Dry Eye Disease: Causes, Symptoms, Treatment & Natural Strategies

A Holistic Approach to Long-Term Dry Eye Relief

Dry eye disease (DED) is one of the most common eye conditions worldwide. It occurs when the eyes do not produce enough tears or when tears evaporate too quickly. Symptoms often include burning, stinging, redness, blurred vision, sensitivity to light, and a gritty or sandy sensation in the eyes.

According to the Tear Film & Ocular Surface Society (TFOS DEWS II) report, dry eye disease is typically driven by multiple factors, including inflammation, meibomian gland dysfunction, hormonal changes, environmental stressors, and nutritional deficiencies.

While many conventional treatments focus on artificial tears, a functional and holistic medicine approach—as practiced by Dr. Samar Shadly—focuses on identifying the root causes of dry eye rather than only treating symptoms.

This approach aims to restore natural tear production and improve tear quality through nutrition, lifestyle interventions, environmental adjustments, and targeted supplementation.

Root Causes of Dry Eye: A Functional & Holistic Perspective

From a functional medicine perspective, dry eye is often a symptom of a larger systemic imbalance.

1. Gut Dysbiosis & Chronic Inflammation

Poor diet, gut microbiome imbalance, and intestinal permeability may promote systemic inflammation that affects the ocular surface.

2. Meibomian Gland Dysfunction (MGD)

Blocked oil glands in the eyelids reduce the lipid layer of the tear film, causing tears to evaporate quickly.

3. Hormonal Changes

Hormonal fluctuations—especially during perimenopause, menopause, thyroid disorders, or autoimmune conditions such as Hashimoto’s—can significantly reduce tear production.

4. Nutrient Deficiencies

Low levels of Omega-3 fatty acids, Vitamin A, Vitamin D, and antioxidants may impair tear quality and ocular surface health.

5. Environmental & Lifestyle Factors

• Excessive screen time and reduced blinking

• Smoking

• Air conditioning or dry indoor environments

• Environmental pollutants

Addressing these factors is essential for long-term improvement.

Natural Strategies to Improve Dry Eye

1. Nutritional Support for Tear Production

Omega-3 Fatty Acids

Omega-3 fatty acids help reduce inflammation and support meibomian gland function.

Nordic Naturals Ultimate Omega

https://amzn.to/4wVKrfk

Metagenics OmegaGenics EPA-DHA

https://amzn.to/4qFhp20

Typical supportive dose used in research: 1–3 g EPA/DHA daily.

Gamma-Linolenic Acid (GLA)

GLA supports anti-inflammatory pathways and may improve tear quality.

Designs for Health GLA

https://amzn.to/4wNxQun

Omega-7 (Sea Buckthorn)

Omega-7 helps support mucous membranes, including the eyes.

Sea Buckthorn Omega-7

https://amzn.to/4y94AQa

Terry Naturally Omega-7

https://amzn.to/4xoXAi4

Vitamin A

Vitamin A plays a critical role in maintaining the health of the ocular surface and supporting tear film stability. Because excessive intake may lead to Vitamin A toxicity, supplementation, particularly at higher doses, should be taken under appropriate medical supervision.

Pure Encapsulations Vitamin A

https://amzn.to/4glOxZ3

Nordic Naturals Vitamin A (with carotenoids)

https://amzn.to/4hXBUEL

Phospholipids for Cellular Health

Phospholipids support cell membrane integrity and mitochondrial function, which are important for eye tissue health.

BodyBio Phosphatidylcholine

https://amzn.to/4iqt96k

Thorne Phosphatidylcholine

https://amzn.to/4wW5rmf

2. Choosing the Right Eye Drops

Preservative-free artificial tears are often recommended to avoid irritation from preservatives.

Systane Ultra Lubricant Eye Drops

https://amzn.to/4wVLKee

TheraTears Nighttime Lubricant Eye Drops

https://amzn.to/4y95IDo

OPTASE Hylo Night Ointment

https://amzn.to/4xyNniQ

3. Warm Compress Therapy

Warm compresses help melt thickened oils in the meibomian glands.

Bruder Moist Heat Eye Compress

https://amzn.to/46niUIH

Electric Heated Eye Mask

https://amzn.to/4qHnpYb

4. Eyelid Hygiene

Proper eyelid hygiene helps reduce bacteria and inflammation.

OCuSOFT Hypochlorous Cleanser

https://amzn.to/3Sh6DSV

OCuSOFT Lid Scrub Cleanser

https://amzn.to/4zKAMec

5. Optimizing the Sleep Environment

Many people experience worsening dryness overnight.

Silk Sleep Eye Mask

https://amzn.to/4cNe5vV

Crane Ultrasonic Humidifier

https://amzn.to/3SquS0Z

Lifestyle Habits That Help Reduce Dry Eye

Follow the 20-20-20 Rule

Every 20 minutes, look 20 feet away for 20 seconds.

Stay Hydrated

Drink enough water throughout the day.

Reduce Screen Strain

Blink consciously when using digital devices.

Manage Stress

Practices such as meditation, yoga, or breathing exercises may help reduce inflammation.

Final Thoughts

Dry eye disease is rarely caused by a single factor. It is usually the result of inflammation, gland dysfunction, hormonal imbalance, environmental stress, and nutritional deficiencies.

A functional medicine approach combines:

• Anti-inflammatory nutrition

• Targeted supplementation

• Eyelid hygiene

• Environmental support

• Lifestyle optimization

This comprehensive strategy may significantly improve symptoms and support long-term eye health.

Book a Functional Medicine Consultation

If you are struggling with dry eye, autoimmune disease, gut inflammation, or chronic fatigue, identifying the root causes may help restore your health.

Book a Functional Medicine Consultation

About Dr. Samar Shadly

Contact Dr. Samar Shadly on WhatsApp to schedule a consultation

Related topics:

What is Sjogren syndrome?

هل يسبب العفن الصداع والتعب وضبابية الدماغ؟ ما تقوله الأدلة

توجد رطوبة أو عفن في المنزل، وفي الوقت نفسه تعاني من الصداع والتعب وصعوبة التركيز. من الطبيعي أن تسأل: هل العفن هو السبب؟

الإجابة الصادقة هي أن بعض الأشخاص الذين يعيشون أو يعملون في مبانٍ رطبة يبلغون عن أعراض عامة مثل الصداع والتعب وصعوبة التركيز. لكن هذه الأعراض غير نوعية، والأدلة على أن استنشاق العفن المنزلي أو السموم الفطرية يسبب متلازمة عصبية جهازية مزمنة ليست بالقوة نفسها التي تدعم ارتباط الرطوبة والعفن بالحساسية والربو والأعراض التنفسية.

هذا لا يعني أن الأعراض متخيلة أو غير مهمة. بل يعني أن تشخيص «سمية العفن» لا ينبغي أن يكون قفزة تلقائية تمنع البحث عن فقر الدم واضطرابات الغدة الدرقية والنوم والأدوية والعدوى وأسباب أخرى أكثر شيوعًا وقابلة للعلاج.

في هذه المقالة سنفصل بين ما ثبت وما يزال محل جدل، ونوضح كيف يُقيّم المريض بطريقة متزنة.

ما المقصود بضبابية الدماغ؟

ضبابية الدماغ ليست تشخيصًا طبيًا محددًا، بل وصف لمجموعة من الصعوبات، مثل:

● ضعف التركيز.

● بطء التفكير.

● صعوبة استدعاء الكلمات.

● النسيان المتكرر.

● الشعور بعدم صفاء الذهن.

● صعوبة إنجاز المهام الذهنية المعتادة.

وقد تظهر هذه الأعراض مع قلة النوم والإجهاد والقلق وبعض الأمراض والالتهابات والأدوية. لذلك لا يمكن معرفة السبب من المصطلح وحده.

ما الأعراض العامة التي ينسبها الناس إلى العفن؟

قد يذكر بعض الأشخاص:

● الصداع.

● التعب المزمن.

● اضطراب النوم.

● صعوبة التركيز أو النسيان.

● الدوار.

● آلام العضلات أو المفاصل.

● تغير المزاج.

● الحساسية للروائح.

لكن جمع عدة أعراض غير نوعية لا يحولها تلقائيًا إلى تشخيص واحد. يجب النظر إلى وقت بدايتها، والتعرضات، والفحوص، والأمراض السابقة، والأدوية، وجودة النوم، ونمط الحياة.

ما الذي ثبت علميًا عن آثار العفن الصحية؟

الأدلة الأقوى حول المباني الرطبة والمتعفنة تتعلق بـ:

● أعراض الأنف والحلق.

● السعال والصفير.

● الحساسية.

● تفاقم الربو أو حدوثه لدى بعض الأشخاص.

● التهاب الرئة بفرط التحسس لدى القابلين للإصابة.

● بعض العدوى الفطرية لدى ضعيفي المناعة أو مرضى رئة محددين.

وتوضح منظمة الصحة العالمية أن أهم الآثار المرتبطة بالرطوبة والعفن داخل المباني هي زيادة الأعراض التنفسية والحساسية والربو.

أما الصداع والتعب وضبابية الدماغ، فقد تُذكر في دراسات أو تقارير عن مبانٍ رطبة، لكن ربطها سببيًا بالمايكوتوكسينات المستنشقة يواجه صعوبات مهمة.

لصورة شاملة: التعرض للعفن: الأعراض والتشخيص والعلاج والوقاية.

لماذا يصعب إثبات أن العفن سبب الصداع والتعب؟

الأعراض غير نوعية

تظهر الأعراض نفسها في عشرات الحالات الطبية والنفسية والبيئية.

التعرض داخل المبنى معقد

قد يحتوي المبنى الرطب على الغبار وعث الغبار والبكتيريا والمواد العضوية المتطايرة ومواد التنظيف وسوء التهوية والحرارة والضوضاء، وليس العفن وحده.

صعوبة قياس التعرض الحقيقي

تتغير مستويات الأبواغ والجزيئات حسب المكان والوقت والتهوية. وعينة هواء قصيرة لا تمثل دائمًا التعرض الطويل.

الاعتماد على الأعراض المبلغ عنها

تعتمد بعض الدراسات على استبيانات دون قياس موضوعي دقيق للتعرض أو دون مجموعة مقارنة كافية، مما يصعب إثبات السببية.

اختبارات تجارية غير موحدة

لا توجد حدود بولية متفق عليها تربط كل نتيجة للمايكوتوكسين بمرض عصبي أو مستوى ضار. وقد يأتي التعرض لبعض السموم الفطرية من الغذاء.

ما متلازمة سمية العفن؟

يستخدم مصطلح Mold Toxicity أو «متلازمة العفن السام» لوصف أعراض متعددة يُفترض أنها ناتجة عن التعرض المزمن للعفن أو السموم الفطرية، مثل التعب والصداع وضبابية الدماغ وتغير المزاج.

لكن الأكاديمية الأمريكية للحساسية والربو والمناعة تشير إلى أن الدراسات التي تدعم هذا الربط تعاني من مشكلات منهجية، وأن اختبارات البول التجارية غير المعتمدة تعاني من غياب التوحيد وعدم وجود حدود تحدد المستوى الضار.

كما تؤكد الكلية الأمريكية لعلم السموم الطبية أن الدليل لا يدعم اعتبار استنشاق المايكوتوكسينات في المنازل سببًا مثبتًا لتسمم جهازي مزمن، وتحذر من الفحوص والعلاجات غير المثبتة.

:الخلاصة

:> يمكن أخذ التعرض للعفن بجدية دون اعتبار «سمية العفن» تشخيصًا محسومًا لكل أعراض غير مفسرة.

هل الصداع قد يرتبط بالعفن بصورة غير مباشرة؟

نعم، توجد طرق غير مباشرة محتملة لا تتطلب افتراض تسمم عصبي:

● احتقان الأنف أو التهاب الجيوب قد يسبب ضغطًا أو ألمًا في الوجه والرأس.

● السعال والربو غير المضبوطين قد يضعفان النوم ويسببان صداع الصباح والتعب.

● الرائحة القوية قد تحفز الصداع النصفي لدى بعض الأشخاص الحساسين للروائح.

● القلق المستمر بشأن المنزل والصحة قد يزيد الصداع والتوتر العضلي.

● سوء التهوية وارتفاع الحرارة أو ملوثات أخرى في المبنى قد تسهم في الأعراض.

لكن الصداع الجديد أو الشديد يحتاج إلى تقييم مستقل، ولا يجوز افتراض أن مصدره العفن.

هل التعب قد ينتج من الحساسية أو الربو؟

قد يسبب التهاب الأنف التحسسي المستمر انسداد الأنف واضطراب النوم، وقد يؤدي الربو الليلي إلى استيقاظ متكرر. النتيجة قد تكون تعبًا وضعف تركيز في النهار.

كذلك قد تسبب بعض مضادات الهيستامين القديمة النعاس والتشوش. وهنا يكون العلاج الصحيح هو تحسين السيطرة على الحساسية أو الربو ومراجعة الدواء، وليس افتراض تراكم السموم.

راجع: حساسية العفن: الأعراض والتشخيص والعلاج.

ما الأسباب الأخرى للصداع والتعب وضبابية الدماغ؟

هذه أهم خطوة في التقييم؛ فالقائمة طويلة، لكن يمكن تنظيمها.

اضطرابات الدم والعناصر الغذائية

● فقر الدم.

● نقص الحديد حتى قبل انخفاض الهيموغلوبين في بعض الحالات.

● نقص فيتامين B12 أو الفولات.

● نقص عناصر أخرى بحسب النمط الغذائي والحالة.

اضطرابات الغدد والأيض

● خمول أو فرط نشاط الغدة الدرقية.

● اضطرابات سكر الدم.

● اضطرابات الكالسيوم أو الصوديوم.

● أمراض الكبد أو الكلى.

اضطرابات النوم

● قلة ساعات النوم.

● انقطاع التنفس الانسدادي أثناء النوم.

● الأرق.

● متلازمة تململ الساقين.

● اضطراب الساعة البيولوجية.

العدوى والالتهابات

● عدوى فيروسية حديثة.

● حالة ما بعد كوفيد الطويل.

● أمراض مناعية أو التهابية.

● عدوى مزمنة في سياق سريري مناسب.

الأدوية والمواد

● مضادات الهيستامين المسببة للنعاس.

● بعض الأدوية النفسية أو المسكنات.

● الكحول أو المهدئات.

● الإفراط في الكافيين أو الانقطاع المفاجئ عنه.

أسباب عصبية ونفسية

● الصداع النصفي.

● القلق والاكتئاب.

● الإجهاد المزمن والاحتراق النفسي.

● اضطراب فرط الحركة ونقص الانتباه لدى بعض البالغين.

● أمراض عصبية أخرى بحسب العمر والأعراض المصاحبة.

التشخيص الجيد لا يطلب جميع الفحوص للجميع؛ بل يوجهها التاريخ والفحص.

هل يمكن أن تكون المشكلة من أول أكسيد الكربون وليس العفن؟

نعم، وهذه نقطة سلامة لا ينبغي تجاهلها. قد يسبب أول أكسيد الكربون الصداع والدوار والضعف والغثيان والتشوش، وقد يتعرض له أكثر من شخص في المنزل في الوقت نفسه، خاصة مع أجهزة الاحتراق أو التدفئة أو التهوية غير السليمة.

إذا ظهرت أعراض متعددة لدى أفراد المنزل وتتحسن بالخروج منه، خصوصًا مع وجود مدفأة أو جهاز غاز، اخرجوا إلى الهواء الطلق واطلبوا المساعدة الطارئة وفحص مصدر الغاز. لا تنتظروا فحص العفن.

كيف أعرف إن كان المبنى مرتبطًا بالأعراض؟

سجل لمدة أسبوعين إلى أربعة أسابيع:

● وقت ومكان ظهور الصداع أو التعب.

● شدته ومدته.

● أيام العمل والإجازات.

● جودة النوم.

● الروائح والرطوبة والتكييف.

● الطعام والكافيين والأدوية.

● الأعراض التنفسية أو التحسسية المصاحبة.

● ما إذا كانت الأعراض تتحسن أثناء السفر.

هذا السجل لا يثبت السبب، لكنه يكشف الأنماط ويمنع الاعتماد على الذاكرة والانطباع فقط.

كيف يتم التقييم الطبي؟

يبدأ التقييم بتاريخ منظم يشمل:

● بداية الأعراض وتسلسلها الزمني.

● التعرض للرطوبة والعفن وأضرار المياه.

● النوم والشخير والنعاس النهاري.

● الدورة الشهرية والنزف عند النساء.

● النظام الغذائي والوزن والنشاط.

● العدوى السابقة.

● الأدوية والمكملات والكافيين.

● الحالة المزاجية والضغط النفسي.

● الأعراض العصبية وعلامات الخطر.

وقد تشمل الفحوص المبدئية، بحسب الحالة:

● صورة الدم الكاملة.

● مخزون الحديد ودراسات الحديد.

● وظائف الغدة الدرقية.

● فيتامين B12 والفولات عند وجود مؤشر.

● سكر الدم ووظائف الكبد والكلى والأملاح.

● تقييم اضطراب النوم.

● تقييم الحساسية والربو إذا وجدت أعراض تنفسية.

لا يوجد «تحليل عفن» واحد يحل محل هذا التقييم.

هل يفيد تحليل السموم الفطرية؟

للتفاصيل: تحليل السموم الفطرية: ماذا يقيس؟ ومتى يكون مفيدًا؟.

ماذا أفعل إذا كان في منزلي عفن مع وجود هذه الأعراض؟

لا تحتاج إلى إثبات أن العفن سبب كل عرض قبل معالجة الرطوبة. اتبع مسارين في الوقت نفسه:

المسار البيئي

1 حدد التسرب أو مصدر الرطوبة.

2. أصلحه.

3. أزل العفن والمواد المتضررة بأمان.

4. حسن التهوية واضبط الرطوبة.

5. استعِن بمتخصص إذا كان الضرر واسعًا أو مخفيًا.

المسار الطبي

1. قيّم علامات الخطر.

2. ابحث عن الأسباب الشائعة للصداع والتعب.

3. عالج الحساسية والربو واضطراب النوم إن وجدت.

4. راقب التحسن بعد معالجة البيئة دون إيقاف العلاجات الطبية.

هذا النهج أكثر فائدة من انتظار اختبار إيجابي قبل إصلاح منزل رطب.

متى يجب مراجعة الطبيب بصورة عاجلة؟

اطلب تقييمًا عاجلًا عند وجود:

● صداع مفاجئ وشديد جدًا.

● ضعف أو خدر في جهة واحدة.

● اضطراب الكلام أو الرؤية.

● إغماء أو تشنج.

● تشوش حاد أو تغير في الوعي.

● حمى مع تيبس الرقبة.

● صداع بعد إصابة في الرأس.

● ضيق تنفس شديد أو انخفاض الأكسجين.

● الاشتباه بأول أكسيد الكربون.

هذه الحالات لا تنتظر موعدًا روتينيًا أو تحليل السموم الفطرية.

أسئلة شائعة

هل يسبب العفن صداعًا يوميًا؟

قد يتزامن الصداع مع وجود مبنى رطب، وقد تسهم الحساسية أو الجيوب أو الروائح أو سوء النوم. لكن الصداع اليومي يحتاج إلى تقييم أسبابه ولا يثبت سمية العفن.

هل تتحسن ضبابية الدماغ عند مغادرة المنزل؟

قد يلاحظ بعض الأشخاص تحسنًا، لكن ذلك لا يحدد المسبب؛ فقد تتغير جودة النوم والضغط والتهوية والروائح والتعرضات الأخرى أيضًا. التحسن يدعم وجود عامل بيئي يستحق البحث ولا يشخّص مادة بعينها.

كم تستمر الأعراض بعد الابتعاد عن العفن؟

لا توجد مدة واحدة. يعتمد ذلك على السبب الحقيقي؛ فالتهيج قد يتحسن سريعًا، بينما تحتاج الحساسية أو الربو أو اضطرابات النوم أو نقص الحديد إلى علاج مستقل.

هل آلام المفاصل من أعراض العفن؟

آلام المفاصل عرض غير نوعي. لا توجد علاقة سببية قوية تسمح بتشخيص سمية العفن اعتمادًا عليها. يجب تقييم الإصابات والالتهابات والأمراض المناعية ونقص بعض العناصر وأسباب أخرى.

هل نتيجة المايكوتوكسين الإيجابية تثبت سبب ضبابية الدماغ؟

لا. تثبت اكتشاف المادة وفق طريقة المختبر، لكنها لا تثبت مصدرها أو أنها سبب العرض.

هل حساسية العفن تسبب التعب؟

قد تسهم بصورة غير مباشرة عبر احتقان الأنف واضطراب النوم أو الربو، لكنها ليست التفسير الوحيد للتعب المزمن.

الخلاصة

قد يبلغ بعض سكان المباني الرطبة عن الصداع والتعب وضبابية الدماغ، لكن الأدلة الأقوى للعفن تتعلق بالحساسية والربو والأعراض التنفسية. أما تشخيص تسمم جهازي مزمن من الأعراض العامة أو تحليل بول تجاري منفرد فليس مثبتًا بما يكفي.

التصرف الصحيح هو:

1. معالجة الرطوبة والعفن لأن وجودهما غير صحي للمبنى مهما كان سبب الأعراض.

2. تقييم الحساسية والربو والنوم عند وجود مؤشرات.

3. البحث عن نقص الحديد والغدة الدرقية والأدوية والعدوى والأسباب الشائعة الأخرى.

4. عدم تجاهل علامات الخطر أو احتمال أول أكسيد الكربون.

5. عدم بناء خطة علاج مكلفة على اختبار واحد أو تشخيص افتراضي

.

إذا كنت تعاني من أعراض مزمنة مع تاريخ تعرض بيئي، فقد يساعد التقييم الشامل في بناء خط زمني

للأعراض، واستبعاد الأسباب الطبية المهمة، وتحديد الفحوص والتدخلات التي ستغير الخطة فعلًا.

احجز استشارتك مع د. سمر شاذلي
Dr. Samar Shadly, MD, IFMCP
استشارية أمراض صدرية وطبيبة معتمدة في الطب الوظيفي
الاستشارات متاحة حاليًا أونلاين.
[للحجز والاستفسار عبر واتساب]

Radical Wellness

المصادر الأساسية

● الأكاديمية الأمريكية للحساسية والربو والمناعة: Toxic Mold Syndrome—Separating Fact from Fiction
https://www.aaaai.org/tools-for-the-public/conditions-library/allergies/toxic-mold

● الأكاديمية الأمريكية للحساسية والربو والمناعة: Mold Allergy
https://www.aaaai.org/conditions-treatments/allergies/mold-allergy

● CDC/NIOSH: Health Problems—Mold
https://www.cdc.gov/niosh/mold/health-problems/index.html

● منظمة الصحة العالمية: Guidelines for Indoor Air Quality—Dampness and Mould
https://www.who.int/publications/i/item/9789289041683

● الكلية الأمريكية لعلم السموم الطبية: Mold-Related Inhalation Exposures
https://www.acmt.net/news/acmt-position-statement-medical-toxicology-considerations-in-thediagnosis-and-treatment-of-patients-with-concerns-aboutmold-related-inhalation-exposures/

● CDC: Use of Unvalidated Urine Mycotoxin Tests
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6406a7.htm

هل يسبب العفن ضيق التنفس والسعال والربو؟ دليل طبي شامل

قد تلاحظ أن السعال أو الصفير يزداد في غرفة رطبة، أو أن ضيق التنفس يتكرر في منزل توجد فيه رائحة عفن، وتتساءل: هل يمكن أن يؤثر العفن فعلًا في الرئتين؟

نعم، قد ترتبط البيئات الرطبة والمتعفنة بالسعال والصفير وضيق التنفس، ويمكن أن تفاقم الربو، خاصة لدى الأشخاص الذين لديهم حساسية للعفن. لكن ليس كل سعال في منزل رطب سببه العفن، كما أن «حساسية الصدر من العفن» قد تشير إلى حالات مختلفة لا تعالج بالطريقة نفسها.

قد تكون المشكلة تهيجًا بسيطًا، أو التهاب أنف تحسسيًا يسبب السعال، أو ربوًا يحتاج إلى علاج منتظم، أو في حالات أقل شيوعًا التهاب الرئة بفرط التحسس أو داء الرشاشيات القصبي الرئوي التحسسي أو عدوى فطرية لدى شخص ضعيف المناعة.

لذلك يجب تحديد النمط السريري بدل افتراض تشخيص واحد لجميع حالات التعرض.

كيف يؤثر العفن في الجهاز التنفسي؟

تنتج الفطريات أبواغًا وجزيئات صغيرة يمكن أن تنتقل عبر الهواء. كما تحتوي البيئات الرطبة على مزيج من مكونات فطرية وبكتيرية وغبار ومسببات حساسية ومهيجات.

قد يؤثر التعرض من خلال عدة آليات:

الحساسية

لدى الشخص المتحسس، قد يتعرف الجهاز المناعي على بعض البروتينات الفطرية بوصفها مسببات للحساسية، فتظهر أعراض الأنف والعينين أو الربو.

التهيج

قد تسبب مكونات البيئة الرطبة تهيج الأنف والحلق والرئتين حتى دون إثبات حساسية، مما يؤدي إلى السعال أو الحرقة أو الانزعاج التنفسي.

تفاقم الربو

قد يعمل العفن أو الرطوبة بوصفهما محفزين للأعراض لدى بعض مرضى الربو، فتزداد التشنجات القصبية والالتهابات وصعوبة التنفس.

استجابة مناعية في أنسجة الرئة

في التهاب الرئة بفرط التحسس، تحدث استجابة مناعية مختلفة في الحويصلات والأنسجة الرئوية بعد التعرض المتكرر لمستضدات مستنشقة، وقد تكون الفطريات من بينها.

العدوى أو الاستعمار الفطري

يصبح هذا الاحتمال أكثر أهمية لدى المصابين بضعف المناعة أو بأمراض رئوية بنيوية معينة، وليس النتيجة المعتادة لكل من يرى عفنًا في المنزل.

ما أعراض العفن على الجهاز التنفسي؟

قد تشمل:

● السعال الجاف أو المصحوب ببلغم.

● الصفير.

● ضيق التنفس.

● ضيق الصدر.

● احتقان الأنف أو سيلانه.

● نزول الإفرازات خلف الحلق.

● بحة أو تهيج الحلق.

● زيادة الحاجة إلى بخاخ الربو الإسعافي.

● الاستيقاظ ليلًا بسبب السعال أو ضيق النفس.

● انخفاض القدرة على المجهود في الحالات الأكثر أهمية.

وجود هذه الأعراض لا يثبت أن العفن هو السبب، لكنه يستحق تقييم العلاقة بالمكان والتوقيت، خاصة عند وجود رطوبة أو أضرار مياه واضحة.

هل يسبب العفن السعال؟

نعم، يمكن أن يرتبط التعرض للعفن أو المباني الرطبة بالسعال بعدة طرق:

● تهيج الأنف والحلق والمجرى التنفسي.

● التهاب الأنف التحسسي ونزول الإفرازات خلف الحلق.

● تحفيز الربو.

● التهاب الرئة بفرط التحسس في حالات مختارة.

● عدوى تنفسية أو فطرية في سياقات محددة.

لكن السعال له أسباب أكثر شيوعًا أيضًا، مثل العدوى الفيروسية والربو والارتجاع المعدي المريئي والتهاب الأنف والأدوية والتدخين. السعال المستمر لا ينبغي أن ينسب إلى العفن قبل تقييم هذه الاحتمالات.

هل يسبب العفن ضيق التنفس؟

قد يظهر ضيق التنفس إذا حفز التعرض الربو أو سبب تهيجًا شديدًا أو ارتبط بمرض رئوي آخر. وقد يصف المريض:

● صعوبة أخذ نفس عميق.

● ثقلًا أو ضيقًا في الصدر.

● نهجانًا عند المجهود.

● صفيرًا عند الزفير.

● ضيقًا يزداد ليلًا أو داخل مكان معين.

لكن ضيق التنفس عرض مهم وله أسباب عديدة، تشمل أمراض القلب والرئة وفقر الدم والجلطات والعدوى والقلق وغيرها. وجود العفن لا يبرر إهمال تقييم الأسباب الخطيرة.

هل العفن يسبب الربو؟

العلاقة ليست بسيطة. تشير الأدلة إلى أن البيئات الداخلية الرطبة والمتعفنة ترتبط بتفاقم أعراض الربو الموجود مسبقًا، وتوجد أيضًا علاقة بينها وبين حدوث ربو جديد لدى بعض الأشخاص.

لكن الربو مرض متعدد العوامل يتأثر بالاستعداد الوراثي والحساسية والعدوى والتلوث والتدخين والتعرضات المهنية وعوامل أخرى. لذلك تكون الصياغة الأدق:

> قد يكون العفن أو المبنى الرطب عاملًا محفزًا أو مساهمًا في الربو، وليس بالضرورة السبب الوحيد.

وتشير استراتيجية GINA الحديثة إلى أن معالجة الرطوبة أو العفن في المنزل قد تقلل أعراض الربو واستخدام الأدوية لدى البالغين.

كيف أعرف أن العفن يحفز الربو؟

يدعم الاحتمال وجود نمط مثل:

● زيادة الصفير أو السعال في مبنى معين.

● تحسن الأعراض في الإجازة أو أثناء السفر.

● تدهور الربو بعد تسرب أو فيضان أو ظهور رائحة رطوبة.

● وجود حساسية مثبتة تجاه نوع فطري متوافق.

● زيادة الحاجة إلى بخاخ الإنقاذ داخل المكان.

● تغير موضوعي في وظائف التنفس مرتبط بفترات العمل أو التعرض.

لكن النمط وحده لا يثبت السببية، لأن المبنى قد يحتوي على محفزات أخرى مثل الغبار والعث والدخان والعطور ومواد التنظيف.

ما الربو المرتبط بالعمل أو المبنى؟

قد يبدأ الربو أو يزداد بسبب تعرض في مكان العمل. ويستحق هذا الاحتمال التفكير عندما:

● تتحسن الأعراض في عطلة نهاية الأسبوع أو الإجازات.

● تسوء بعد الوصول إلى العمل.

● ظهرت بعد أضرار مياه أو انتقال إلى مبنى جديد.

● يعاني زملاء آخرون من أعراض تنفسية.

قد يشمل التقييم تسجيل الأعراض، وقياسات ذروة الجريان في العمل وخارجه، ووظائف التنفس واختبارات الحساسية بحسب الحالة. لا ينبغي ترك الوظيفة أو اتخاذ قرار كبير اعتمادًا على الشعور وحده قبل تقييم منظم، إلا إذا كانت الأعراض شديدة أو البيئة غير آمنة بوضوح.

ما الفرق بين حساسية العفن والربو؟

قد تسبب حساسية العفن أعراضًا في الأنف والعينين فقط، بينما الربو مرض التهابي في الشعب الهوائية يسبب أعراضًا متغيرة وتضيقًا في مجرى الهواء.

|حساسية الأنف من العفن           |الربو المحفز بالعفن                                           |
|--------------------------------|--------------------------------------------------------------|
|عطاس وحكة وسيلان أو احتقان      |سعال وصفير وضيق تنفس وصدر                                     |
|تتركز في الأنف والعينين         |تتركز في الشعب الهوائية                                       |
|يُقيّم التحسس باختبار الجلد أو IgE|يحتاج إلى أعراض متوافقة وإثبات تغير في تدفق الهواء عند الإمكان|
|قد توجد دون ربو                 |قد يترافق مع حساسية الأنف أو يحدث دونها                       |

راجع: حساسية العفن: الأعراض والتشخيص والعلاج.

ما التهاب الرئة بفرط التحسس؟

التهاب الرئة بفرط التحسس Hypersensitivity Pneumonitis مرض مناعي يصيب الأجزاء الدقيقة من الرئة بعد التعرض لمستضدات مستنشقة لدى شخص قابل للإصابة. وقد تكون الفطريات أو البكتيريا أو بروتينات الطيور أو مصادر أخرى من المحفزات.

قد تشمل الأعراض:

● السعال.

● ضيق التنفس.

● تراجع القدرة على المجهود.

● تعبًا وأحيانًا حمى أو قشعريرة بعد التعرض.

● نقص الأكسجين في بعض الحالات.

لا يساوي هذا المرض حساسية الأنف ولا يُشخّص باختبار حساسية العفن وحده. يعتمد التشخيص على جمع التاريخ البيئي مع التصوير المقطعي عالي الدقة ووظائف التنفس، وقد يحتاج إلى فحوص إضافية ضمن تقييم متعدد التخصصات.

التعرض المستمر في بعض الحالات قد يؤدي إلى تليف رئوي، لذلك لا ينبغي اختزال ضيق التنفس المتزايد في «حساسية بسيطة» دون تقييم.

ما داء الرشاشيات القصبي الرئوي التحسسي؟

داء الرشاشيات القصبي الرئوي التحسسي ABPA استجابة مناعية معقدة تجاه فطر الرشاشيات، تظهر أساسًا لدى بعض مرضى الربو أو التليف الكيسي، وقد ترتبط بتوسع الشعب الهوائية.

قد يُشتبه به عند وجود:

● ربو يصعب ضبطه.

● تفاقمات متكررة.

● ارتفاع واضح في IgE الكلي أو تحسس للرشاشيات ضمن السياق المناسب.

● ارتشاحات رئوية أو توسع في الشعب الهوائية.

● بلغم سميك أو سدادات مخاطية في بعض الحالات.

هذه الحالة تحتاج إلى تشخيص وعلاج متخصص، ولا يعني اختبار حساسية إيجابي للرشاشيات وحده وجود ABPA.

هل يسبب العفن عدوى في الرئة؟

العدوى الفطرية الغازية ليست النتيجة المعتادة للتعرض المنزلي عند الشخص السليم. يرتفع الخطر خصوصًا لدى:

● مرضى زراعة الأعضاء أو الخلايا الجذعية.

● من لديهم نقص شديد في كريات الدم البيضاء.

● من يتلقون أدوية مثبطة للمناعة بجرعات كبيرة.

● بعض مرضى السرطان.

● من لديهم أمراض رئوية بنيوية أو تجاويف رئوية، بحسب نوع العدوى.

قد تظهر حمى وسعال وضيق نفس وألم صدري أو نفث دموي، لكن الأعراض تختلف. ويحتاج ضعيف المناعة الذي يتعرض للعفن مع أعراض تنفسية إلى تقييم مبكر.

هل العفن الأسود أخطر على الرئتين؟

لا يمكن الحكم على الخطر من اللون وحده. «العفن الأسود» وصف شائع وليس تشخيصًا لنوع فطري. ولا تستطيع الصورة أو البقعة السوداء تحديد ما إذا كان التعرض سيؤدي إلى حساسية أو ربو أو مشكلة أخرى.

أي نمو عفن داخل المنزل يعني وجود رطوبة يجب إصلاحها. اقرأ: العفن الأسود: هل هو خطير؟ الأعراض وطرق التخلص منه.

كيف يتم تشخيص ضيق التنفس المرتبط بالعفن؟

لا يوجد اختبار واحد يثبت أن العفن سبب ضيق النفس. يبدأ التقييم بالأسئلة التالية:

● متى بدأ السعال أو ضيق التنفس؟

● هل يرتبط بمكان أو موسم محدد؟

● هل توجد رطوبة أو أضرار مياه أو رائحة عفن؟

● هل تتحسن الأعراض بعيدًا عن المكان؟

● هل يوجد ربو أو حساسية أو مرض رئوي سابق؟

● هل يوجد تدخين أو شيشة أو تعرض مهني؟

● هل توجد أعراض قلبية أو فقر دم أو أسباب أخرى؟

وقد تشمل الفحوص، بحسب الحالة:

● قياس الأكسجين.

● وظائف التنفس قبل موسع الشعب وبعده.

● اختبار تحفيز الشعب في حالات مختارة.

● قياس ذروة الجريان المتكرر.

● اختبارات حساسية موجهة.

● صورة صدر أو أشعة مقطعية عند وجود مؤشر.

● تحاليل أو فحوص إضافية لالتهاب الرئة بفرط التحسس أو ABPA أو العدوى.

أما تحليل السموم الفطرية في البول فلا يشخّص الربو ولا يثبت أن ضيق التنفس ناتج عن العفن.

كيف يُعالج السعال وضيق التنفس المرتبط بالعفن؟

يعتمد العلاج على التشخيص الفعلي.

معالجة الرطوبة والعفن

أصلح التسرب، وجفف المواد الرطبة، وأزل العفن والمواد المتضررة. معالجة البيئة ليست تفصيلًا؛ فقد تساعد في تقليل أعراض الربو والتعرض المستمر.

علاج التهاب الأنف

قد يقلل غسل الأنف بالمحلول الملحي وبخاخ الكورتيزون الأنفي أو مضادات الهيستامين المناسبة نزول الإفرازات والسعال المرتبط بالأنف، وفق تقييم الطبيب.

علاج الربو

يحتاج الربو إلى علاج استنشاقي يحتوي على الكورتيزون بحسب شدة الحالة والخطة الطبية، مع تعليم طريقة استخدام البخاخ وتقييم الالتزام والمحفزات. لا يُعالج الربو ببخاخ موسع قصير المفعول وحده بصورة متكررة، ولا بمكملات «إزالة السموم».

علاج الأمراض الرئوية المحددة

قد يحتاج التهاب الرئة بفرط التحسس إلى إزالة المستضد وعلاج متخصص. ويختلف علاج ABPA والعدوى الفطرية بحسب التشخيص، ولا يجب استخدام مضادات الفطريات لمجرد وجود عفن في المنزل.

هل يجب مغادرة المنزل؟

يعتمد القرار على:

● مساحة الضرر وشدة الرطوبة.

● شدة الأعراض.

● وجود ربو غير مضبوط أو نقص أكسجين.

● ضعف المناعة.

● احتمال انتشار العفن أثناء أعمال المعالجة.

قد يكون الابتعاد المؤقت مناسبًا أثناء إصلاح تلوث واسع أو عندما تزداد الأعراض بوضوح، لكن الحل النهائي هو معالجة مصدر الرطوبة. الانتقال دون إصلاح المشكلة لا يحمي من عودة العفن، والبقاء في بيئة تسبب تفاقمًا شديدًا ليس خيارًا حكيمًا.

هل يفيد جهاز تنقية الهواء؟

قد تساعد مرشحات HEPA على تقليل بعض الجزيئات المحمولة بالهواء، لكنها لا تصلح التسرب ولا تزيل العفن النامي داخل المواد. وقد يصبح جهاز التنقية إضافة مساعدة بعد معالجة مصدر الرطوبة، وليس بديلًا عنها.

كما يجب صيانة أجهزة التكييف والمرشحات؛ فالنظام الملوث أو سيئ التصريف قد يساهم في نشر الرطوبة والجزيئات.

متى يكون ضيق التنفس طارئًا؟

اطلب المساعدة الطبية العاجلة عند وجود:

● ضيق تنفس شديد أو متزايد بسرعة.

● صعوبة الكلام بجمل كاملة.

● ازرقاق الشفاه أو الوجه.

● انخفاض واضح في الأكسجين.

● ألم صدر شديد أو إغماء.

● عدم الاستجابة لبخاخ الإنقاذ وفق خطة الربو.

● نفث دموي.

● حمى وضيق تنفس لدى شخص ضعيف المناعة.

لا تنتظر تنظيف المنزل أو نتيجة فحص حساسية إذا كانت القدرة على التنفس تتدهور.

أسئلة شائعة عن العفن والجهاز التنفسي

كم يستمر ضيق التنفس بعد الابتعاد عن العفن؟

تختلف المدة حسب السبب. قد يخف التهيج سريعًا، بينما يستمر التهاب الأنف أو الربو أو التهاب الرئة ويحتاج إلى علاج. استمرار الأعراض لا يثبت بقاء «سموم» في الجسم.

هل بخار العفن أو رائحته يسبب الاختناق؟

الرائحة مؤشر على الرطوبة أو النمو الميكروبي، وقد تثير الانزعاج أو الأعراض لدى بعض الأشخاص، لكنها لا تقيس تركيز العفن أو السمية. ضيق النفس الشديد يحتاج إلى تقييم مهما كان مصدر الرائحة.

هل اختبار حساسية العفن يشخّص سبب ضيق التنفس؟

قد يثبت التحسس لمسبب فطري، لكنه لا يثبت أن العفن هو السبب الوحيد ولا يشخّص الربو. يجب ربطه بالأعراض ووظائف التنفس والتعرض.

هل تحليل السموم الفطرية يشخّص حساسية الصدر؟

لا. تحليل البول يقيس مواد مختلفة، ولا يشخّص الربو أو حساسية العفن أو التهاب الرئة بفرط التحسس.

هل يمكن أن يكون السعال من الجيوب الأنفية وليس الرئتين؟

نعم. نزول الإفرازات خلف الحلق سبب شائع للسعال، وقد يترافق مع الربو أو الارتجاع. لذلك يحتاج السعال المزمن إلى تقييم شامل.

هل الأطفال أكثر عرضة؟

قد يرتبط السكن في بيئات رطبة ومتضررة بالعفن بأعراض تنفسية وربو لدى الأطفال أيضًا. يجب معالجة الرطوبة وتقييم السعال أو الصفير المتكرر لدى طبيب الأطفال أو اختصاصي الصدر والحساسية.

الخلاصة

قد يسبب التعرض للعفن أو المباني الرطبة السعال والصفير وضيق التنفس، وقد يفاقم الربو. لكنه ليس تشخيصًا واحدًا، بل تعرض قد يرتبط بحالات متعددة:

● تهيج الجهاز التنفسي.

● حساسية الأنف أو العفن.

● الربو.

● التهاب الرئة بفرط التحسس.

● ABPA في سياق محدد.

● عدوى فطرية لدى الأشخاص المعرضين.

الخطوات الصحيحة هي:

1. تقييم شدة ضيق التنفس واستبعاد الخطر العاجل.

2. تحديد النمط السريري وإجراء وظائف التنفس عند الحاجة.

3. معالجة الرطوبة والعفن بصورة صحيحة.

4. علاج الربو أو الحساسية أو المرض الرئوي المثبت.

5. عدم الاعتماد على لون العفن أو تحليل بول لتشخيص سبب الأعراض.

إذا كنت تعاني من سعال أو صفير أو ضيق تنفس مستمر مع تاريخ تعرض للرطوبة أو العفن، فقد يساعد التقييم الصدري والوظيفي الشامل على التمييز بين الحساسية والربو والأمراض الرئوية الأخرى، وتحديد الفحوص والعلاج المناسبين.

احجز استشارتك مع د. سمر شاذلي
Dr. Samar Shadly, MD, IFMCP
استشارية أمراض صدرية وطبيبة معتمدة في الطب الوظيفي
الاستشارات متاحة حاليًا أونلاين.
[للحجز والاستفسار عبر واتساب]

Radical Wellness 

المصادر الأساسية

● CDC/NIOSH: Health Problems—Mold
https://www.cdc.gov/niosh/mold/health-problems/index.html

● منظمة الصحة العالمية: Guidelines for Indoor Air Quality—Dampness and Mould
https://www.who.int/publications/i/item/9789289041683

● Global Initiative for Asthma: GINA 2026 Strategy Report
https://ginasthma.org/wp-content/uploads/2026/05/GINA-2026-Strategy-Report-WMS.pdf

● منظمة الصحة العالمية: Asthma Fact Sheet
https://www.who.int/news-room/fact-sheets/detail/asthma

● American Thoracic Society/JRS/ALAT: Diagnosis of Hypersensitivity Pneumonitis in Adults
https://www.atsjournals.org/doi/full/10.1164/rccm.202005-2032ST

● CDC: Mold—Possible Health Effects
https://www.cdc.gov/mold-health/about/index.html

السموم الفطرية في جسم الإنسان: الأنواع، مصادر التعرض والأضرار الصحية

عندما يسمع الناس مصطلح السموم الفطرية، يفكر كثير منهم مباشرة في العفن الأسود داخل المنزل. لكن الجزء الأكبر من الأدلة العلمية المتعلقة بأضرار السموم الفطرية على الإنسان يرتبط بتلوث الأغذية، وليس بمجرد رؤية بقعة عفن على الجدار.

السموم الفطرية أو المايكوتوكسينات Mycotoxins مواد حقيقية تستطيع بعض الفطريات إنتاجها في ظروف معينة. وقد تسبب جرعات مرتفعة من بعض الأنواع تسممًا حادًا، بينما يرتبط التعرض الغذائي المزمن لبعضها بأضرار صحية طويلة المدى. ومع ذلك، ليس كل عفن منتجًا للسموم، ولا يعني وجوده في المنزل أن سكانه مصابون بتسمم فطري.

في هذه المقالة سنشرح أنواع السموم الفطرية، وكيف تدخل الجسم، وما آثارها المثبتة، والفرق بين التسمم الغذائي والتعرض للعفن داخل المباني، وكيف يمكن تقليل التعرض دون الوقوع في الخوف أو برامج «الديتوكس» غير المثبتة.

ما هي السموم الفطرية؟

السموم الفطرية مركبات كيميائية تنتجها أنواع معينة من الفطريات. ويمكن لبعض هذه الفطريات أن تنمو على المحاصيل أثناء الزراعة أو الحصاد أو التخزين، خصوصًا مع الحرارة والرطوبة وسوء التجفيف والتخزين.

ومن الأجناس الفطرية المهمة في هذا السياق:

● Aspergillus

● Penicillium

● Fusarium

لكن وجود أحد هذه الأجناس لا يثبت أنه أنتج سمومًا؛ فالإنتاج يعتمد على السلالة والظروف البيئية والمادة التي ينمو عليها الفطر.

كيف تدخل السموم الفطرية إلى جسم الإنسان؟

1.تناول الأغذية الملوثة

هذا هو الطريق الأكثر أهمية من ناحية الصحة العامة والأدلة العلمية. قد تتلوث بعض المحاصيل قبل الحصاد أو أثناء التخزين، وقد تبقى بعض السموم موجودة حتى إذا لم يعد العفن ظاهرًا.

2.تناول منتجات حيوانية معينة

قد تنتقل بعض المستقلبات إلى منتجات حيوانية؛ فمثلًا يمكن أن يظهر الأفلاتوكسين M1 في الحليب إذا تناول الحيوان علفًا ملوثًا.

3. الاستنشاق في بيئات مهنية محددة

قد يحدث تعرض استنشاقي في البيئات الزراعية أو الصناعية التي تحتوي على غبار ملوث بمواد عضوية أو محاصيل متعفنة. لكن هذا السياق يختلف عن افتراض حدوث تسمم جهازي من مستويات العفن المعتادة في منزل رطب.

. التعرض داخل المباني الرطبة

تحتوي البيئات الرطبة على خليط من الأبواغ والشظايا الفطرية والبكتيريا ومسببات الحساسية والمهيجات. وترتبط هذه البيئات بأعراض تنفسية وحساسية وتفاقم الربو. لكن وجود فطر قادر على إنتاج سموم لا يعني أن المايكوتوكسينات موجودة بجرعة ضارة أو أنها سبب الأعراض العامة.

ما أشهر أنواع السموم الفطرية؟

الأفلاتوكسينات

تنتج أساسًا عن بعض أنواع Aspergillus، وقد ترتبط بالذرة والفول السوداني والمكسرات والبذور وبعض الأغذية المخزنة في ظروف حارة ورطبة.

يمكن للجرعات الكبيرة أن تسبب تسممًا حادًا خطيرًا مع أذية الكبد. أما التعرض المزمن للأفلاتوكسين B1 فيرتبط بزيادة خطر سرطان الكبد، ويصبح الخطر أعلى عند اجتماع التعرض مع عدوى التهاب الكبد الفيروسي B.

الأوكراتوكسين A

يمكن أن يوجد في بعض الحبوب والقهوة والكاكاو والزبيب والتين المجفف وغيرها. وقد أظهرت الدراسات الحيوانية تأثيرات في الكلى، بينما يعتمد تقدير الخطر البشري على مستوى التعرض ومدته والبيانات المتاحة.

الفومونيزينات

ترتبط بصورة خاصة بالذرة ومنتجاتها، وتنتجها بعض أنواع Fusarium. وتراقبها الجهات التنظيمية بسبب آثارها المحتملة في الصحة عند التعرض الغذائي المرتفع.

الديوكسينيفالينول

يعرف أيضًا باسم DON أو «سم القيء»، وقد يوجد في القمح والشعير والحبوب. قد يؤدي التعرض المرتفع إلى الغثيان والقيء واضطرابات الجهاز الهضمي، وتُحدد له مستويات إرشادية في الغذاء والعلف.

الباتولين

يرتبط خصوصًا بالتفاح المتعفن وبعض منتجاته أو عصائره عند سوء التصنيع أو التخزين. ولهذا يخضع للمراقبة في الأغذية.

الزيرالينون

تنتجه بعض أنواع Fusarium، وله نشاط شبيه بالإستروجين في الحيوانات. ولا يجوز تحويل نتائج الدراسات الحيوانية مباشرة إلى تشخيص اضطرابات هرمونية لدى الإنسان دون دليل سريري مناسب.

سموم T-2 وHT-2

تنتمي إلى مجموعة الترايكوثيسينات، وقد تلوث بعض الحبوب. وترتبط الجرعات المرتفعة بتأثيرات سامة مختلفة، وتراقبها الجهات المختصة بسلامة الغذاء.

ما أعراض التسمم بالسموم الفطرية؟

لا توجد قائمة واحدة تنطبق على جميع السموم الفطرية. تختلف الأعراض باختلاف المادة والجرعة وطريق التعرض والمدة والحالة الصحية.

التسمم الحاد

قد يحدث بعد تناول كمية كبيرة من غذاء شديد التلوث، وقد تشمل المظاهر بحسب المادة:

● الغثيان والقيء.

● ألم البطن أو الإسهال.

● فقدان الشهية والضعف.

● أذية الكبد واليرقان في التسمم الشديد بالأفلاتوكسين.

● النزف أو اضطراب التخثر في الحالات الشديدة.

● اضطرابات عصبية أو مناعية أو دموية مع أنواع وجرعات معينة.

التسمم الحاد الحقيقي حالة طبية، وليس مجرد شعور بالتعب بعد دخول غرفة رطبة.

التعرض المزمن

قد يرتبط التعرض الغذائي المزمن لبعض المواد بآثار طويلة المدى. المثال الأقوى هو ارتباط الأفلاتوكسين ب1 بسرطان الكبد. أما الآثار الأخرى فتختلف قوة الأدلة بشأنها بحسب المادة والسكان ومستوى التعرض.

هل تسبب السموم الفطرية التعب والصداع وضبابية الدماغ؟

تنتشر على الإنترنت قوائم طويلة تنسب للمايكوتوكسينات التعب والصداع واضطراب النوم وضبابية الدماغ وآلام المفاصل وعشرات الأعراض الأخرى.

المشكلة أن هذه الأعراض غير نوعية، وقد تنتج عن:

● نقص الحديد أو فقر الدم.

● اضطرابات الغدة الدرقية.

● انقطاع التنفس أثناء النوم.

● العدوى والالتهابات.

● اضطرابات سكر الدم.

● بعض الأدوية.

● القلق والاكتئاب والإجهاد المزمن.

● أمراض مناعية أو عصبية أو هرمونية مختلفة.

قد يبلغ شخص يعيش في مبنى رطب عن هذه الأعراض، لكن التزامن لا يثبت أن استنشاق السموم الفطرية هو السبب. يجب تقييم التعرض مع الصورة الطبية الكاملة وعدم تحويل «سمية العفن» إلى تشخيص يفسر كل شيء.

ما الفرق بين السموم الفطرية وحساسية العفن؟

|حساسية العفن                            |السموم الفطرية                             |
|----------------------------------------|-------------------------------------------|
|استجابة مناعية لمسبب حساسية فطري        |مركبات كيميائية تنتجها بعض الفطريات        |
|قد تسبب عطاسًا واحتقانًا وحكة وصفيرًا      |تختلف آثارها حسب النوع والجرعة وطريق التعرض|
|يمكن تقييمها باختبار الجلد أو IgE الموجه|لا يشخصها اختبار الحساسية                  |
|وجودها لا يعني وجود تسمم                |وجود مادة في البول لا يثبت سبب المرض       |

للمزيد: حساسية العفن: الأعراض والتشخيص والعلاج.

ما الفرق بين السموم الفطرية والعفن الأسود؟

«العفن الأسود» وصف للون وليس اسمًا لمادة سامة واحدة. وقد ارتبط المصطلح إعلاميًا بفطر Stachybotrys chartarum، لكن لا يمكن تحديد نوع الفطر أو خطره من اللون وحده.

ليس كل عفن أسود منتجًا للسموم، وليس كل فطر منتج للسموم أسود اللون. كما أن وجود فطر قادر على إنتاج المايكوتوكسينات لا يثبت أنه ينتجها في ذلك المكان.

راجع: العفن الأسود: هل هو خطير؟ الأعراض وطرق التخلص منه.

هل العفن الموجود في الطعام ينتج سمومًا فطرية دائمًا؟

لا. لكن الطعام المتعفن قد يحتوي على نمو ممتد لا يظهر كله على السطح، خصوصًا في الأطعمة الطرية أو المسامية. كما قد تكون السموم موجودة دون مظهر واضح للعفن.

لا يكفي إزالة الجزء المتعفن من كل غذاء وافتراض أن الباقي آمن. تختلف التوصيات بحسب نوع الطعام وصلابته ودرجة التلف، والأكثر أمانًا هو التخلص من الأغذية الطرية أو الرطبة المتعفنة، وعدم شم الطعام المتعفن عن قرب.

هل الطبخ يزيل السموم الفطرية؟

ليس بالضرورة. بعض السموم الفطرية مقاوم نسبيًا للحرارة، وقد لا يزيلها الطبخ المنزلي المعتاد بالكامل. لذلك تعتمد الوقاية أساسًا على سلامة الزراعة والحصاد والتجفيف والتخزين والمراقبة التنظيمية، وليس على محاولة «تعقيم» غذاء متعفن في المنزل.

كيف يتعامل الجسم مع السموم الفطرية؟

بعد دخول المادة عبر الجهاز الهضمي، قد تُمتص وتخضع للاستقلاب في الكبد أو أنسجة أخرى، ثم تُطرح المادة أو مستقلباتها عبر البول أو البراز بطرق تختلف بحسب نوعها.

لا يعني وجود مستقلب في البول أن السم «مخزن» في الجسم أو أنه يسبب أعراضًا. كما لا تعني سرعة الإخراج أو بطؤه وجود «مسارات ديتوكس مسدودة» دون دليل سريري وبيوكيميائي مناسب.

هل يمكن قياس السموم الفطرية في جسم الإنسان؟

توفر بعض المختبرات اختبارات بول تجارية تقيس مواد أو مستقلبات محددة. لكن النتيجة لا تحدد تلقائيًا مصدر التعرض أو توقيته أو ما إذا كان المستوى يسبب مرضًا.

قد يأتي التعرض من الغذاء، وقد توجد مستويات منخفضة لدى أشخاص أصحاء. كما لا توجد حدود سريرية متفق عليها لكل اختبار تربط النتيجة بمتلازمة مرضية ناتجة عن العفن المنزلي.

لهذا لا ينبغي استخدام النتيجة وحدها لتشخيص «سمية العفن» أو تبرير برنامج علاجي مكلف.

للتفاصيل: تحليل السموم الفطرية: ماذا يقيس؟ ومتى يكون مفيدًا؟.

كيف يتم تشخيص التسمم الحقيقي بالسموم الفطرية؟

يعتمد التشخيص على السياق، وقد يشمل:

● وجود تعرض غذائي أو مهني معقول وموثق.

● ظهور أعراض تتوافق مع المادة والجرعة والتوقيت.

● تقييم عدة أشخاص تعرضوا للمصدر نفسه عند حدوث تفشٍّ غذائي.

● فحص الغذاء أو المصدر المشتبه به عبر جهات مختصة.

● فحوص وظائف الكبد والكلى والتخثر والدم بحسب الحالة.

● استبعاد العدوى والأدوية والسموم والأسباب الطبية الأخرى.

لا يُشخّص التسمم الحاد من قائمة أعراض عامة أو من فحص بول تجاري منفرد.

ما علاج السموم الفطرية في الإنسان؟

لا يوجد علاج واحد لجميع المايكوتوكسينات. وتعتمد الخطة على نوع التعرض وشدته والحالة السريرية.

إيقاف مصدر التعرض

في التسمم الغذائي، يجب التوقف عن تناول المصدر المشتبه به وحفظ العبوة أو العينة عند الحاجة للتقييم الرسمي. وفي البيئة الرطبة، يجب إصلاح مصدر الماء وإزالة العفن.

الرعاية الطبية الداعمة

قد يحتاج التسمم الحاد إلى تقييم سوائل الجسم ووظائف الكبد والكلى والتخثر، وعلاج الأعراض والمضاعفات في المستشفى بحسب الشدة.

علاج الحالة الفعلية

إذا كانت المشكلة حساسية أو ربوًا، فالعلاج يكون بعلاج الحساسية والربو. وإذا كانت عدوى فطرية، فتحتاج إلى تشخيص وعلاج مضاد للفطريات وفق الحالة. هذه الحالات ليست مرادفات للتسمم الفطري.

هل توجد حمية لإزالة السموم الفطرية؟

لا توجد حمية مثبتة «تسحب» السموم الفطرية من الجسم. ويمكن اتخاذ إجراءات معقولة لسلامة الغذاء دون الدخول في حميات قاسية:

● تنويع مصادر الغذاء بدل الاعتماد على محصول واحد بكميات كبيرة.

● شراء الأغذية من مصادر موثوقة.

● تجنب المكسرات والحبوب ذات الرائحة أو الطعم غير الطبيعي.

● التخلص من الطعام المتعفن بصورة مناسبة.

● حفظ الحبوب والمكسرات والأطعمة الجافة في مكان بارد وجاف.

● عدم تناول منتجات انتهت صلاحيتها أو ساء تخزينها.

● اتباع تحذيرات الجهات الصحية عند سحب منتج من السوق.

الحميات شديدة التقييد قد تؤدي إلى نقص غذائي وقلق غير ضروري، خصوصًا إذا لم يوجد تعرض مثبت.

كيف أقلل التعرض الغذائي للسموم الفطرية؟

توصي منظمة الصحة العالمية بممارسات عملية، منها:

● فحص الحبوب والمكسرات والفواكه المجففة وتجنب ما يبدو متعفنًا أو متغير اللون أو منكمشًا.

● شراء المنتجات الطازجة قدر الإمكان ومن مصادر موثوقة.

● حفظ الطعام بطريقة جافة وباردة ومناسبة.

● عدم الاحتفاظ بالأطعمة الجافة فترات طويلة في ظروف رطبة.

● اتباع نظام غذائي متنوع لتقليل التعرض المتكرر لمادة واحدة.

المستهلك لا يستطيع التحكم في كل مستويات التلوث، ولذلك تلعب الرقابة على الغذاء والتخزين وسلاسل الإمداد دورًا أساسيًا.

كيف أقلل التعرض للعفن داخل المنزل؟

● أصلح التسربات ومصادر الماء سريعًا.

● جفف المواد الرطبة خلال 24–48 ساعة قدر الإمكان.

● حافظ على الرطوبة الداخلية دون 60%، ويفضل بين 30% و50%.

● صُن أجهزة التكييف ومسارات تصريف المياه.

● عالج التكثف وضعف التهوية.

● أزل المواد المسامية شديدة التلف.

● استعِن بمتخصص إذا كان الضرر واسعًا أو وصل إلى التكييف.

إصلاح الرطوبة أكثر أهمية من معرفة لون العفن أو محاولة تحديد قائمة السموم المحتملة.

متى يجب طلب المساعدة الطبية؟

اطلب تقييمًا عاجلًا عند وجود:

● قيء أو إسهال شديد بعد تناول طعام مشتبه به.

● اصفرار العينين أو الجلد.

● ألم شديد في البطن.

● نزف أو كدمات غير معتادة.

● اضطراب في الوعي أو أعراض عصبية حادة.

● ضيق تنفس شديد أو تدهور حاد في الربو.

● حمى وأعراض تنفسية لدى شخص ضعيف المناعة.

أما الأعراض المزمنة غير النوعية فتحتاج إلى تقييم منظم للأسباب الشائعة والتعرضات بدل البدء بتحليل أو بروتوكول إزالة سموم تلقائيًا.

أسئلة شائعة عن السموم الفطرية

هل كل الفطريات تنتج سمومًا فطرية؟

لا. تنتج أنواع وسلالات معينة سمومًا محددة في ظروف مناسبة، وليس كل نمو فطري منتجًا للسموم.

هل وجود العفن في المنزل يعني وجود السموم الفطرية في الجسم؟

لا. يثبت وجود مشكلة رطوبة تحتاج إلى معالجة، لكنه لا يثبت وصول سموم بجرعة ضارة أو أنها سبب الأعراض.

هل السموم الفطرية معدية؟

لا. السم مادة كيميائية وليست عدوى تنتقل من شخص إلى آخر.

هل السموم الفطرية هي نفسها العدوى الفطرية؟

لا. العدوى تعني نمو الفطر داخل الجسم، بينما السموم الفطرية مركبات تنتجها بعض الفطريات.

هل يمكن رؤية السموم الفطرية أو شمّها؟

لا يمكن الاعتماد على الرؤية أو الرائحة لاكتشاف السم نفسه. وقد يوجد تلوث غذائي دون عفن واضح.

هل النتيجة الإيجابية في البول تعني وجود تسمم؟

لا. تعني اكتشاف مادة وفق طريقة المختبر، لكن لا تثبت مصدرها أو أنها تسبب المرض.

ما أكثر السموم الفطرية خطورة؟

يعتمد الخطر على الجرعة والمدة وطريق التعرض. ويعد الأفلاتوكسين

من أهمها صحيًا بسبب ارتباطه بتسمم الكبد وسرطان الكبد عند التعرض الغذائي المزمن.

الخلاصة

السموم الفطرية مواد حقيقية قد تلوث الأغذية، وقد تسبب آثارًا حادة أو مزمنة بحسب نوعها وجرعتها. لكن الحقيقة التي يجب عدم تجاوزها هي أن:

● الغذاء هو المصدر الأهم الذي تستند إليه معظم أدلة الضرر البشري.

● ليس كل عفن منتجًا للسموم.

● وجود العفن في المنزل لا يثبت التسمم.

● التعب والصداع لا يشخصان سمية العفن.

● نتيجة البول الإيجابية لا تحدد المصدر أو السببية بمفردها.

إذا كانت لديك أعراض مستمرة مع تاريخ تعرض للعفن أو قلق بشأن نتيجة تحليل، يمكن للتقييم الطبي الشامل أن يفرق بين الحساسية والربو والتعرض الغذائي والأسباب الطبية الأخرى، ويحدد ما إذا كانت هناك حاجة إلى فحوص إضافية أو تدخل بيئي.

احجز استشارتك مع د. سمر شاذلي
Dr. Samar Shadly, MD, IFMCP
استشارية أمراض صدرية وطبيبة معتمدة في الطب الوظيفي
الاستشارات متاحة حاليًا أونلاين.
[للحجز والاستفسار عبر واتساب]

Radical Wellness 

المصادر الأساسية

● منظمة الصحة العالمية: Mycotoxins Fact Sheet
https://www.who.int/news-room/fact-sheets/detail/mycotoxins

● إدارة الغذاء والدواء الأمريكية: Mycotoxins
https://www.fda.gov/food/natural-toxins-food/mycotoxins

● الهيئة الأوروبية لسلامة الأغذية: Mycotoxins
https://www.efsa.europa.eu/en/topics/topic/mycotoxins

● الكلية الأمريكية لعلم السموم الطبية: Mold-Related Inhalation Exposures
https://www.acmt.net/news/acmt-position-statement-medical-toxicology-considerations-in-thediagnosis-and-treatment-of-patients-with-concerns-aboutmold-related-inhalation-exposures/

● منظمة الصحة العالمية: Food Safety
https://www.who.int/news-room/fact-sheets/detail/food-safety

● إدارة الغذاء والدواء الأمريكية: Natural Toxins in Food
https://www.fda.gov/food/chemical-contaminants-pesticides/natural-toxins-food