Do PFAS cause weight gain?
Researchers from Tulane University, Louisiana State University, and Harvard School of Public Health recently took a second look at data from 621 overweight and obese men and women in the Prevention of Obesity Using Novel Dietary Strategies (POUNDS LOST) clinical trial, which was conducted in the mid-2000s.
During the first 6 months of the trial, the participants lost on average 14 pounds. But over the course of the next 18 months, they regained on average about 6 pounds.
Link strongest among women
The investigators found that the participants who had regained the most weight were the ones who also had the highest blood levels of PFAS, and the link was strongest among women.
So, do PFAS cause weight gain?
Correlation does not equal causation
“It’s much too early to know,” says Seth Marquit, MD, Medical Director at the Pritikin Longevity Center in Miami, which has been helping people shed weight and live healthier since 1975. “It’s important to remember that this study established correlation but not causation.”
In other words, it could be that it’s not the PFAS themselves that cause increased weight gain but rather something else about people with higher levels of PFAS.
Highly processed, fattening foods
Concentrations of PFAS tend to higher in processed, high-calorie-dense foods – in containers for fast foods, for example, in cans of soda pop, and in the packaging used in super-processed, ready-made foods, from pies to frozen pizzas.
It could well be that it’s a diet full of these fattening, highly processed foods that is causing the weight gain, not the PFAS-containing packaging that they’re wrapped in.
“We need more research,” sums up Jay Kenney, PhD, RD, FACN, nutrition research specialist at the Pritikin Longevity Center.
“But if I had to bet, my guess is that PFAS may correlate with weight gain simply because they tend to be in higher amounts in processed foods – foods well known for their ability to pack on the pounds.
“I’d also bet that PFAS are negatively correlated with a naturally fiber-rich, whole foods diet like the Pritikin Eating Plan. You aren’t going to find many PFAS in the produce aisle.”
PFAS and other health concerns
More research is needed not only on PFAS and body weight but also on PFAS and other health issues like cancers, hormone disruptions, and immune dysfunctions.
Media sites like to grab us with gotta-click headlines like “PFAS cause cancer,” but researchers cringe at such drama. States the Centers for Disease Control: “Scientists are still learning about the health effects of exposures to mixtures of PFAS.”
“In observational studies, higher blood levels of PFAS have been inconsistently correlated with a somewhat higher risk of some cancers. And it is still unclear whether they may be promoting cancer directly, states Dr. Kenney.
“Research in animals shows only very high exposure levels seem to have adverse effects on the immune system, liver, and thyroid, and may impact some hormone levels.”
“Because animals and humans process these chemicals differently,” states the CDC, “more research will help scientists fully understand how PFAS affect human health.”