PFAS vs Diet for Weight Outcomes

Could it be that exposure to endocrine disrupting chemicals such as PFAS has more of an effect on body weight and adiposity than diet? Philippe Grandjean and colleagues this week published a new study in Obesity that points to this possibility. Grandjean tells us:

“We’ve previously shown that children with increased PFAS concentrations tend to gain weight and develop higher levels of cholesterol in the blood. We now focused on adults who participated in an experimental study of five different diets in regard to weight gain. Our results add to the concern that environmental pollution may be affecting our metabolism, so that we tend to gain weight.”

Data from the DioGenes Study

The Diet, Obesity and Genes (DioGenes) study was a European multicenter trial, conducted from 2006 to 2008. It originally focused on the importance dietary protein and the glycemic index of carbohydrates for weight management. Participants were randomized to one of five diets.

But in this new analysis, Grandjean et al took advantage of data on baseline exposures to PFAS in 381 subjects from that study. They looked at the relationship of diet and PFAS levels to weight gain in the maintenance phase of this study. The authors tell us:

“Baseline plasma PFAS concentrations were significantly associated with greater weight gain by 26 weeks after an initial weight loss. The weight gain associated with elevated PFAS exposures exceeded the differences in weight gain linked to suboptimal study diets.”

A Troubling Association

The association of PFAS exposure with weight gain in this study is cause for concern, even if it is not definitive evidence of causality. The authors explain:

“As experimental studies of PFAS exposures in humans are not possible, this trial, in conjunction with related experimental and epidemiological evidence, offers support to a hypothesis of PFAS obesogenicity, although it cannot prove causality by itself.”

In yet another recent study, Jesse Goodrich and colleagues demonstrated that PFAS exposure is linked to amino acid and lipid metabolism in young persons.

So we have little reason to doubt the wisdom of recent action by the U.S. Environment Protection Agency to start taking PFAS out of our drinking water. It’s about time.

Click here for the study by Grandjean et al, here for the Goodrich study, and here for further perspective.

Chemical Works, photograph by Roger Kidd, licensed under CC BY-SA 2.0

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April 21, 2023