MedicalResearch.com Interview with:
Gang Liu, PhD
Postdoctoral Research Fellow
Department of Nutrition
Harvard T.H. Chan School of Public Health
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Although many approaches can be used to achieve a short-term weight loss, maintenance of weight loss has become a key challenge for sustaining long-term benefits of weight loss. Accumulating evidence has suggested that certain environmental compounds may play an important role in weight gain and obesity development.
The potential endocrine-disrupting effects of perfluoroalkyl substances (PFASs), which are extensively used in many industrial and consumer products including food packaging, paper and textile coatings, and non-stick cookware, have been demonstrated in animal studies, but whether PFASs may interfere with body weight regulation in humans is largely unknown.
In a 2-year POUNDS Lost randomized clinical trial that examined energy-restricted diets on weight changes, baseline plasma concentrations of major PFASs were measured among 621 overweight and obese participants aged 30-70 years. Body weight was measured at baseline, 6, 12, 18, and 24 months. Resting metabolic rate (RMR) and other metabolic parameters, including glucose, lipids, thyroid hormones, and leptin, were measured at baseline, 6, and 24 months.
We found that higher baseline levels of PFASs were significantly associated with a greater weight regain, primarily in women. On average, women in the highest tertile of PFASs regained 1.7-2.2 kg more body weight than women in the lowest tertile. In addition, higher baseline plasma PFAS concentrations, especially perfluorooctanesulfonic acid (PFOS) and perfluorononanoic acid (PFNA), were significantly associated with greater decline in RMR during the first 6 months and less increase in RMR during weight regain period.
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