An easy-to-understand guide to PFAS exposure, the liver–bile–gut loop and the emerging science of viscous fibre.

“Detox” is one of the vaguest words in wellness. It can imply that a tea, powder or cleanse somehow locates unwanted chemicals and washes them away. Human biology is more organised and more interesting: compounds are absorbed, transported, transformed, filtered and excreted through specific pathways.

Sometimes, however, a compound moving towards an exit enters the intestine and is absorbed again. This recycling is called enterohepatic recirculation. Emerging research into PFAS is asking whether certain gel-forming dietary fibres could interrupt part of that loop and increase elimination.

 

PFAS Is a Chemical Family, Not One Chemical

PFAS stands for per- and polyfluoroalkyl substances. These synthetic chemicals have been used because some resist water, oil, grease and heat. Those useful properties can also make certain PFAS highly persistent in the environment and slow to leave the human body, which is why they are often called “forever chemicals”.

PFOA and PFOS are among the most studied, but the family contains thousands of compounds with different chain lengths, structures, uses, persistence and biological behaviour. A claim that “fibre removes PFAS” is therefore immediately too broad. The real questions are: which PFAS, which fibre, what dose, for how long, and compared with what?

 

Exposure Reduction Comes Before “Detox”

People can encounter PFAS through different routes, including contaminated water or food, dust, occupational settings, some consumer products and food-contact materials. The dominant source differs by location and circumstance. No single household swap removes all exposure.

Australian public-health guidance recommends minimising exposure as a precaution, particularly in known affected communities. If drinking water or locally sourced food is known to be contaminated, follow advice from the relevant health and environmental authorities rather than relying on a supplement.

·       Check local advice where PFAS contamination has been identified.

·       Use tested, appropriately certified water treatment only when it is relevant to the water source.

·       Reduce unnecessary contact between hot food and plastic where practical.

·       Follow local fish, water and food advisories rather than generic social-media lists.

·       Do not let chemical anxiety crowd out eating enough nutritious food.

 

For the body’s real processing and elimination systems, read Understanding the Body's Natural Detoxification Systems: Nutrition, Protein & Everyday Wellbeing.

The Liver–Bile–Gut Loop

The liver receives compounds from circulation and from the digestive tract via portal blood. It processes nutrients, medicines, hormones and environmental chemicals. Some substances or their metabolites can be released into bile, which flows into the small intestine.

Bile is best known for helping digest and absorb fats. It also creates a route from the liver into the gut. But the intestine is designed to absorb. A compound entering bile does not automatically leave the body in stool; some can cross the intestinal wall and return to circulation.

 

 

This continuous exchange is explored more broadly in The Gut-Liver Connection: How Your Digestive Health Influences Metabolic Health.

Why Viscous Fibre Is Being Studied

Dietary fibre is not one ingredient. Fibres differ in solubility, viscosity, particle size, fermentability and how they interact with water and the intestinal environment. Oat and barley beta-glucans and psyllium can form viscous solutions or gels under suitable conditions, while many other fibres behave differently.

Viscous fibre is already studied in relation to bile-acid recycling and blood cholesterol. If a gel-forming fibre changes how bile and intestinal contents move or interact, researchers can ask whether it also reduces the opportunity for selected PFAS to be reabsorbed.

The proposed mechanism does not require fibre to chemically neutralise or break down PFAS. It may be enough to retain more of a compound in the intestinal contents until it leaves in stool. This is a transport and excretion question, not a magical cleansing reaction.

For the wider roles of dietary fibre, read Why Fibre Feeds More Than Your Gut and Gut Microbes Feed on Fibre: Why Diversity Matters More Than One Superfood.

What the Human Pilot Actually Found

A 2025 peer-reviewed pilot analysis examined PFAS concentrations in a Canadian male population and included a four-week dietary-fibre intervention. Participants consumed either an oat beta-glucan preparation or a brown-rice control with meals.

The oat beta-glucan group showed a statistically significant reduction in a measure of long-chain PFAS, with the signal driven particularly by PFOA and PFOS. University reporting described an approximately eight per cent decrease in PFOS and PFOA after four weeks.

 

Why It Is Not Yet Definitive

·       It was a pilot and secondary analysis, not a large definitive PFAS-treatment trial.

·       The intervention lasted four weeks.

·       The participants were men, so generalisation requires care.

·       The result concerned a defined oat beta-glucan preparation, not all dietary fibre.

·       Not every PFAS necessarily responded in the same way.

·       Lower blood concentration does not by itself prove improved health outcomes.

·       Replication, dose-response research and longer follow-up are still needed.

This distinction makes the research more credible, not less. Early human evidence is valuable when described at the correct scale.

Lower Blood PFAS Is Not the Same as Proven Removal

A falling blood concentration is an important outcome, but it does not tell the entire toxicokinetic story. A compound can move between blood and tissues, and laboratory measurements capture a particular sample at a particular time. To show that an intervention truly increases elimination, researchers ideally need to measure what leaves through stool or urine as well as what remains in blood.

The strongest future studies would combine repeated blood measurements with faecal PFAS analysis, carefully recorded diet, bowel patterns and exposure assessment. That would help distinguish increased excretion from ordinary variation, reduced recent exposure or movement between body compartments.

Clinical relevance is another step again. Even if a study reliably lowers a PFAS concentration, researchers still need to determine whether the change is large enough and sustained long enough to influence health. Body-burden evidence and health-outcome evidence are connected, but they are not interchangeable.

Oat Beta-Glucan Is Not Mushroom Beta-Glucan

The word beta-glucan covers a family of polysaccharides. Oat and barley beta-glucans have structural features associated with viscosity. Yeast and mushroom beta-glucans have different branching patterns and are commonly investigated in other areas of biology. Sharing a name does not make them interchangeable.

Functional mushrooms contain fibres and other compounds that can influence microbial fermentation in laboratory studies. That may be relevant to the microbiome, but it does not establish that mushroom powders reduce PFAS or remove microplastics in humans.

The structural differences are explained in Beta-Glucans Explained: Benefits for Immunity, Gut Health, Cholesterol, Brain Health & Functional Nutrition; for the wider evidence on mushrooms, see Functional Mushrooms & Brain Health: What the Evidence Says.

 

PFAS and Microplastics Are Different Questions

PFAS and microplastics are often grouped together because both relate to modern materials and environmental exposure. Chemically, they are not the same. PFAS are defined chemicals; microplastics are small plastic particles with varied polymers, sizes, shapes and associated chemicals.

A fibre that influences the intestinal reabsorption of a PFAS molecule does not automatically capture or remove a plastic particle. Each claim needs its own mechanism, measurement method and human evidence. “Environmental detox” is too broad to be scientifically useful.

Where the Microbiome May Enter the Story

The gut is not only a tube through which compounds pass. It is an ecosystem containing microorganisms, mucus, enzymes, bile acids, immune cells and constantly changing food residues. Microbes can modify bile acids and produce metabolites from fermentable fibre, so it is reasonable to ask whether microbiome differences affect PFAS handling.

Reasonable does not mean proven. The oat beta-glucan hypothesis centres mainly on physical properties such as viscosity and bile-related recycling. Fermentation may occur as well, but a change in short-chain fatty acids or microbial abundance would not by itself demonstrate greater PFAS elimination.

This is an important example of scientific restraint. Researchers can investigate whether microbial composition, transit time or bile-acid metabolism predicts the response to fibre without claiming that “good bacteria detox forever chemicals”.

For the difference between fibre fermentation and direct contaminant elimination, explore Short-Chain Fatty Acids Explained: How Your Gut Microbes Turn Fibre into Health-Supporting Compounds.

Bowel Function Matters, but More Is Not Always Better

A compound retained in intestinal contents can only leave when those contents leave. This makes bowel transit a plausible part of the elimination pathway. However, that does not make laxatives, extreme cleanses or deliberately induced diarrhoea appropriate PFAS strategies.

Normal, comfortable bowel function is the goal. Very high supplemental fibre can cause bloating, pain, constipation or diarrhoea, particularly when increased quickly or taken without enough fluid. Fibre can also alter the timing or absorption of some medicines.

A sensible approach is to build fibre through food, increase gradually and seek individual advice when digestive disease, altered anatomy, swallowing difficulty, medication timing or longstanding constipation complicates the picture.

What a Food-First Approach Can Do Now

The current evidence does not justify prescribing an oat beta-glucan supplement as a universal PFAS treatment. It does support the broader, already useful practice of eating fibre-rich foods as part of a healthy dietary pattern.

Include a range of fibre sources because they do different jobs: oats and barley can provide beta-glucan; legumes provide varied fermentable and non-fermentable fibres; vegetables, fruit, nuts, seeds and whole grains add further structures and phytochemicals.

 

Increase fibre gradually if intake has been low, drink enough fluid and consider individual tolerance. People with swallowing difficulties, bowel obstruction risk, severe gastrointestinal disease or medications affected by fibre timing need personalised advice before using concentrated fibre supplements.

For microbiome variety, explore Microbiome Diversity Explained: Why Variety Is One of the Best Things You Can Feed Your Gut and Short-Chain Fatty Acids Explained: How Your Gut Microbes Turn Fibre into Health-Supporting Compounds.

Where Broth + Co Foods Fit

Bone broth does not supply the viscous fibre studied in the PFAS pilot, and it should not be described as removing PFAS. Its role is different: it can contribute protein and collagen-associated amino acids to meals containing legumes, whole grains, vegetables and mushrooms.

That food-first role is explained in Bone Broth Benefits: The Complete Guide to Gut Health, Protein, Recovery & Healthy Ageing.

The mushroom ingredients used in Broth + Co products should also remain within the evidence for mushroom nutrition, polysaccharides and microbiome research. They should not be presented as proven PFAS or microplastic detoxifiers.

 

The Detox Evidence Ladder

 

The oat beta-glucan pilot provides early human body-burden evidence for selected PFAS. It does not yet reach established clinical-outcome evidence. Mushroom products remain below human elimination evidence for PFAS and microplastics.

What Better PFAS–Fibre Research Should Ask Next

The pilot opens a useful door, but many decisions remain unresolved. A larger trial should be designed specifically around PFAS rather than analysing the outcome secondarily. It should include a diverse population, appropriate controls, verified fibre preparations and enough follow-up to understand whether changes persist.

·       Compare characterised fibres such as oat beta-glucan, barley beta-glucan and psyllium rather than treating “fibre” as one category.

·       Measure individual PFAS compounds, including long-chain and short-chain examples.

·       Record recent exposure so lower intake is not mistaken for greater elimination.

·       Measure blood and faecal concentrations repeatedly.

·       Assess dose, viscosity, medicine interactions and gastrointestinal tolerance.

·       Examine whether sex, age, baseline PFAS burden, bile-acid metabolism, bowel transit or the microbiome changes the response.

·       Determine whether any reduction is maintained after the intervention stops.

·       Eventually test whether a meaningful reduction changes validated health outcomes.

 

Frequently Asked Questions

Can eating more fibre remove PFAS from the body?

We do not yet know that fibre in general removes PFAS. A small human pilot found modest reductions in selected long-chain PFAS after a defined oat beta-glucan intervention. Larger trials are needed.

Is oat beta-glucan the same as mushroom beta-glucan?

No. Their structures and physical behaviour differ. Evidence from an oat preparation cannot be transferred automatically to mushrooms.

Does fibre destroy PFAS?

The proposed mechanism is not chemical destruction. Viscous fibre may reduce intestinal reabsorption and help more of a compound remain in the contents leaving the body.

Can mushrooms detox PFAS?

Human trials have not established that mushroom foods or supplements reduce PFAS body burden.

Can fibre remove microplastics?

PFAS and microplastics are different. Evidence about PFAS recirculation does not prove removal of plastic particles.

Should everyone take a fibre supplement for PFAS?

No. The evidence is preliminary, and supplements can affect digestion, swallowing and medicine timing. Food-first fibre and professional advice are more appropriate starting points.

What is enterohepatic recirculation?

It is the movement of a compound from circulation to the liver, into bile and the intestine, followed by reabsorption back into circulation.

What is the best way to reduce PFAS exposure?

Follow local health and environmental advice, especially for contaminated water or food. Reduce meaningful exposure where practical rather than relying on an unproven detox product.

Final Thoughts

The most memorable part of this research is not the discovery of a new detox food. It is the possibility that nutrition may alter one measurable step in the journey of a specific persistent chemical.

PFAS can enter bile without necessarily leaving the body. Some may be reabsorbed from the intestine. A sufficiently viscous fibre may influence that return journey. If larger human trials confirm the effect, dietary fibre could eventually become one part of a compound-specific strategy to increase elimination.

For now, oat beta-glucan is promising, fibre variety remains valuable for broader health, functional mushrooms deserve direct testing, and exposure reduction still comes first. That conclusion is quieter than detox marketing, but scientifically it is far more useful.

For practical fibre-rich meal ideas, browse the collection of nourishing recipes.

References and Further Reading

·       Australian Government enHealth guidance on PFAS

·       Schlezinger et al. 2025: oat beta-glucan pilot and serum PFAS

·       UMass Lowell research summary: fibre supplements and PFAS

·       US EPA: meaningful steps to reduce PFAS exposure

·       US EPA: reducing PFAS in drinking water with a home filter