Eating More Fiber Could Lower Levels of PFAS ‘Forever Chemicals’: Study

A new study has found that eating higher amounts of dietary fiber can reduce the levels of two of the most common per- and polyfluoroalkyl substances (PFAS) “forever chemicals.”

The researchers discovered that fiber was most effective at reducing perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), each of which can remain in the human body for years, reported The Guardian. Federal data has shown that the chemicals are present in the blood of almost everyone on the planet.

“The general public is exposed to PFASs via ingestion of contaminated food and drinking water and use of consumer products that contain PFAS,” the authors of the findings wrote. “Despite the growing concerns about the toxicity of PFAS, specific interventions to reduce PFAS levels in the body are limited. Recent epidemiological studies suggest one potential strategy. Investigation of dietary patterns and PFAS body burdens show that the consumption of fruits or vegetables and fiber-rich diets are associated with lower serum-PFAS concentrations in both adults and children.”

Jennifer Schlezinger, lead author of the study and an associate professor of environmental health at Boston University, said the research team was “excited” about the results of recent studies, and that a larger study was planned.

“We’re still mid-experiment but we’re seeing very promising things,” Schlezinger said, as The Guardian reported. “The key is that this is feasible, accessible and economical.”

PFAS — a group of approximately 15,000 chemical compounds — are often used in firefighting foams and to make products nonstick, as well as stain- and water-resistant. They are referred to as “forever chemicals” because they can take hundreds or even thousands of years to break down naturally in the environment.

PFAS have been associated with cancer, kidney disease, decreased immunity, birth defects, high cholesterol and many other serious health conditions.

The United States Environmental Protection Agency has said that there is no level of PFOS or PFOA that is safe in drinking water, and it can take decades for the human body to fully get rid of PFAS.

The researchers hypothesized that a gel formed by dietary fiber could stop the gut’s cell lining from absorbing PFAS. They noted that the gel interferes with the absorption of bile acids, which have a similar chemical makeup to long-chain PFAS.

“[L]ife-style changes designed to reduce serum cholesterol via increasing dietary fiber were shown to be associated with reductions in serum- PFAS. One explanation for this association is that dietary fibers may impede the absorption or reabsorption of PFAS by cells lining the gut. In fact, gel forming, soluble dietary fibers decrease the absorption of bile acids leading to increased bile acid elimination in feces,” the authors wrote in the findings.

Schlezinger said both soluble and insoluble fibers were necessary. She added that oat beta glucan was also effective, but should be taken with a meal because that’s when bile is produced by the body, and bile production must be timed with the consumption of fiber.

“Oat β-glucan is one such dietary fiber that has been shown to reduce serum cholesterol by enhancing bile acid elimination. Bile acids are chemically similar to long-chain PFAS… Thus, gel-forming dietary fibers may enhance elimination of PFAS as they do bile acids,” the authors wrote.

The study, “Per- and poly-fluoroalkyl substances (PFAS) in circulation in a Canadian population: their association with serum-liver enzyme biomarkers and piloting a novel method to reduce serum-PFAS,” was published in the journal Environmental Health.