PFAS, known as “forever chemicals,” are used in many waterproof fabrics and nonstick products, but can also make their way into drinking water and some foods. They have been associated with potential health harms. Photo via iStock/ronstik

PFAS

What Are PFAS? And Could Fiber Supplements Help Remove Them from Our Bodies?

BU study suggests common dietary supplement could decrease levels of the forever chemicals

They’re used to make coats waterproof, pans nonstick, and furniture stain resistant; they’re even effective at fighting fuel fires. But for all their amazing properties, PFAS have a dark side: nature, including human bodies, can’t figure out how to break them down. They are forever chemicals. 

“Every person in the United States, essentially, is walking around with PFAS in their body,” says Jennifer Schlezinger, a Boston University School of Public Health professor of environmental health. PFAS—per- and polyfluoroalkyl substances—are associated with reduced ability to have an immune response to a vaccine, high cholesterol liver toxicity, hypertensive disorders of pregnancy, and low birth weights in infants.

But Schlezinger may have discovered a potential way to flush them out of our systems. In a new study, she found taking a fiber supplement with meals could reduce the levels of PFAS in the body. The results were published in Toxicology and Applied Pharmacology, a peer-reviewed scientific journal.

“The real concern with PFAS is that they’re water-soluble,” she says. “Many of the toxic chemicals in our environment, the man-made ones, tend to dissolve in water. People are largely being exposed through contaminated drinking water, through contaminated food, and then, in part, from products within one’s home.”

A separate BU study found elevated PFAS levels in people who were exposed to them in their drinking water and in some foods, including seafood, eggs, and brown rice. But Schlezinger discovered that fiber supplements taken with a meal are like a PFAS magnet, attracting the forever chemicals and bringing them along as they exit your body. 

A “Life Meets Science Moment”

An expert in molecular toxicology, Schlezinger has long studied the role of environmental toxins in disease development and adverse health effects. But her latest breakthrough on reducing PFAS levels in human bodies started when she was looking for natural ways to lower her cholesterol—it was, she says, a “life meets science moment.”

Schlezinger wanted to reduce her cholesterol, but didn’t want to take a drug, so she started researching dietary interventions and found that gel-forming dietary fibers might help. One such fiber is cholestyramine, which, when taken with food, binds to bile acid and leaves the body with it after digestion. The body then has to replace the bile acid lost, and draws cholesterol from the blood to do so, reducing cholesterol levels. 

Schlezinger realized that PFAS, like bile acids, are surfactants, with a neutral end and a charged end, which is what makes the acids stick to the fibers. She wondered if gel-forming fibers could help us expel PFAS just as they do with bile acids.

“PFAS really easily enter the body, but the problem comes in that we can’t break them down, and we can’t get them out of the body,” Schlezinger says. “Something I tell my toxicology students all the time is a key principle in toxicology: the longer something stays in the body, the more likely it is to cause toxicity. So, because PFAS can’t leave the body easily, they build up in concentration.”

With her colleague at University of Massachusetts Lowell, Dhimiter Bello, Schlezinger planned a couple of pilot studies, including in humans. Using samples from a clinical trial of an oat beta-glucan supplement—a gel-forming fiber—Schlezinger and Bello found a statistically significant effect on PFAS levels. 

They then took their hypothesis—that taking a gel-forming fiber with a meal would decrease levels of PFAS in the body, as well as reducing cholesterol—to the Department of Defense, which funded further studies through its Toxic Exposures Research Program. The program’s goal is to “prevent, minimize and mitigate the impact of military-related toxic exposures and improve the health and quality of life of those affected”; exposure to a military base is reportedly a risk factor for high PFAS. Schlezinger has also been working with Chelsea Simone, an Army veteran and nurse practitioner who advises Schlezinger’s team on veterans’ concerns.

Now, Schlezinger is continuing her work, testing seven different diets to determine the optimal gel-forming fiber to use to decrease PFAS levels.

There are also limitations to the original pilot study that she’d like to tackle. Before the trial with cholestyramine, the only way to get PFAS out of your body was bloodletting, or phlebotomy. People who menstruate tend to have lower PFAS body burdens, so Schlezinger says it made sense to do the trial only on people with particularly high levels of PFAS: men. She also notes that while they found a statistically significant effect, she and Bello couldn’t control for continued exposure to PFAS, and subjects only took the supplement for four weeks.

“We want to figure out if we’re right: Is the hypothesis correct when we are testing it in a very controlled scenario?” Schlezinger says. “Also, we’ve chosen two fibers to work with to begin with, but there are other gel-forming fibers, and perhaps combinations of gel-forming fibers that might work best. So we want to maximize how well this approach works.”

Rollbacks on PFAS Limits

Since the Trump administration announced rollbacks on limits for PFAS in drinking water in March, they have been a hot topic. Schlezinger thinks the rollbacks are a mistake, but says the process is ongoing, so nothing has changed yet. 

“It’s not good news by any way, shape, or form,” Schlezinger says. “But PFAS are not threatening people any more than they are right now.” 

And, as far as her research is concerned, Schlezinger wants to be clear: eating a high-fiber diet is not necessarily what she’s recommending. A dietary supplement, she says, is more accessible, and people are much more likely to take it than they are to change their whole diet. 

“What is exciting about this potential intervention is its accessibility,” she says. “It’s feasible. I bought every single supplement, every single fiber that I’m testing, on Amazon.” (One of the best-known gel-forming fibers is psyllium, the key ingredient in Metamucil.) 

Even then, the pilot study is just the start: “I don’t want to imply that you’re going to take a fiber supplement for a few months and the PFAS are going to be gone,” Schlezinger says.

Of course, she adds, people should speak to a doctor before increasing their fiber intake significantly—but it’s doable. For over two years, Schlezinger, and, begrudgingly, her husband (his review of the taste: “gross”), have been taking a scoop of oat beta-glucan, the original gel-forming fiber she tested, mixing it in pomegranate juice and drinking it with meals. 

“It’s done amazing things for my cholesterol,” Schlezinger says. “I don’t have to take any drugs. I’m back to normal.”