(Amanda MacMillan/ Time) — Chemicals known as perfluoroalkyl substances (PFAS)—used frequently in fast-food wrappers and other products for their oil- and water-repellant properties—have been linked to hormone disruption, immune dysfunction, high cholesterol and even cancer. Now, a new study suggests that exposure to the chemicals could make it harder to keep weight off after dieting.
The study, published in PLOS Medicine, found that levels of PFAS in the blood were linked to greater weight gain in a group of people who had recently shed pounds, especially among the women. Another finding may hint at why: People with higher blood levels of PFAS also had lower resting metabolic rate, meaning they burned fewer calories during normal daily activities.
PFAS are already referred to by scientists as “obesogens,” or chemicals that disrupt normal metabolic processes and increase the chances of weight gain across one’s life. Previous research—mostly in animals—has also found links between the chemicals and obesity. But that hasn’t stopped PFAs from being widely used in products such as food wrappers, paper and textile coatings and non-stick pots and pans.
These chemicals can also accumulate in the food chain and have been found in water supplies near industrial sites, military bases and wastewater treatment plans throughout the United States. Researchers studied health records from a group of 621 overweight and obese people who had participated in a two-year weight-loss clinical trial in the mid-2000s, looking specifically at the amount of PFAS in the participants’ bloodstreams when they first entered the trial. (…)