Flame retardant linked to obesity in mice.
Mice fed high-fat diets gained about 30 percent more weight than other mice eating the same foods when they also ingested high doses of a flame retardant, according to a new study out of Japan.
It’s the first study to show that a brominated flame retardant may accelerate weight gain, raise blood sugar and contribute to metabolic disorders such as diabetes.
The flame retardant, hexabromocyclodecane (HBCD), is used in building materials and insulation. It accumulates in the tissues of animals and humans, and previous animal studies have shown that it may disrupt hormones, metabolism and immune systems.
Too many calories plus not enough exercise are major obesity drivers but emerging evidence suggests that exposure to some hormone-disrupting chemicals, particularly in early development, may also play a role. Some evidence, mostly with lab animals, suggests that prenatal exposure to these “obesogens” can reprogram metabolism, leading to more fat cells and raising the risk of obesity later in life, particularly in those eating high-calorie or high-fat diets.
The findings suggest that HBCD “may contribute to enhancement of diet-induced body weight gain and metabolic dysfunction,” the authors wrote in the study published online last week in the journal Environmental Health Perspectives.
In the study, researchers split 46 adult male mice into groups receiving either a high-fat or normal diet with or without a flame retardant over a 15-week period.
The mice fed a high-fat diet with a high dose of the flame retardant gained an average of 21 grams while mice fed the same diet without the chemical gained about 16 grams. While 5 grams doesn’t seem like much, to a mouse, the difference is substantial. At the onset, the mice weighed on average 21 grams. That means mice fed the high-fat diet plus high levels of flame retardant doubled their weight.
No link to obesity, however, was found in the mice that ate a normal diet even if they were dosed with the flame retardant. “In contrast, no alterations in body and liver weight were observed in normal-diet fed mice with or without HBCD,’ the authors wrote.
