A diet rich in fibre could help reduce levels of toxic PFAS (per-and polyfluoroalkyl substances) – otherwise known as "forever chemicals” – in the body, according to two recent US studies involving mice and a small group of humans.

The scourge of non-governmental organisations (NGOs) and environmental associations alike, PFAS are virtually unavoidable. 

Composed of a powerful combination of carbon and fluorine that makes them highly resistant, PFAS exist in their thousands, and are known as forever chemicals because of the very long time they take to degrade (hundreds, even thousands of years). 

They are found in many everyday products, like paints, varnishes, pesticides, textiles, food packaging, waterproofing, Teflon coatings, toilet paper, etc. 

And this is not without consequences. 

Considered to be endocrine disruptors, PFAS are increasingly highlighted in scientific literature as risk factors for human health. 

In particular, they are thought to be linked to certain cancers (testicular, breast, kidney). 

Significant and prolonged exposure to PFAS can also promote obesity, raise cholesterol levels and cause complications during pregnancy, particularly an increased risk of miscarriage or high blood pressure (pre-eclampsia).

The more PFAS we ingest, the more problematic they can become. 

Several scientific studies have shown that certain foods, such as fish and seafood, contain high levels of PFAS. 

This is particularly true of shrimp and lobster, according to an American study published in April 2024, as well as eels, according to research carried out in the Netherlands, published in 2019. 

But it seems that there are other foods that could help reduce levels of forever chemicals in the body. 

This is the case of fibre-rich foods, according to a study published in the journal Environmental Health. 

Researchers at Boston University in the United States collected blood samples from 72 men living in Canada, from a clinical trial testing the efficacy of a dietary fibre-based intervention to reduce cholesterol. 

The researchers re-analysed these samples – this time to determine whether the blood was contaminated with PFAS.

After four weeks of observation, the researchers found that eating fibre-rich foods was associated with a reduction in PFOS (perfluorooctane sulphonate) and PFOA (perfluorooctanoic acid) – two of the most widespread and dangerous types of forever chemicals – in the participants' blood. 

One of the explanations put forward by the study's authors to explain this phenomenon is that dietary fibre favours the formation of a protective gel that lines the gut, potentially hindering the absorption of these chemicals. 

Another study, published December 2024 by the same team of scientists – this time involving mice – came to a similar conclusion. 

"This observation suggests that a sustained dietary fibre intervention may reduce long-chain PFAS body burden, but future intervention studies need to control for PFAS exposure sources and extend the dietary supplement intake beyond four weeks," the researchers caution.

In any case, fibre-rich foods such as fruit (especially dried fruit), vegetables, wholegrain cereals, legumes and nuts, have many proven health benefits: they are known to regulate appetite, improve intestinal transit, strengthen the microbiota, reduce blood sugar peaks and reduce the risk of cardiovascular (heart) disease. – AFP Relaxnews