Abstract
•It has been hypothesized that endocrine disruptors can enhance obesity risk.•The interaction of soy and bisphenol A (BPA) on body weight was examined.•Dams on soy diet ate more but gain less weight than conspecifics on soy-free diet.•Offspring of soy-fed pups were heavier and females had earlier puberty.•Puberty was also accelerated in females placed on soy diet at weaning.•Males reared on soy diet were heavier throughout life.•Males exposed to BPA and soy, but not BPA alone, had lighter testes.
Endocrine disrupting compounds (EDCs) are hypothesized to promote obesity and early puberty but their interactive effects with hormonally active diets are poorly understood. Here we assessed individual and combinatorial effects of soy diet or the isoflavone genistein (GEN; administered as the aglycone genistin GIN) with bisphenol A (BPA) on body weight, ingestive behavior and female puberal onset in Wistar rats. Soy-fed dams gained less weight during pregnancy and, although they consumed more than dams on a soy-free diet during lactation, did not become heavier. Their offspring (both sexes), however, became significantly heavier (more pronounced in males) pre-weaning. Soy also enhanced food intake and accelerated female pubertal onset in the offspring. Notably, pubertal onset was also advanced in females placed on soy diet at weaning. Males exposed to BPA plus soy diet, but not BPA alone, had lighter testes. BPA had no independent effects.