The findings, yet to be confirmed in humans, could explain why Asians have lower rates of obesity and cancer, said the Duke researchers. Asians consume large amounts of soy, which has been linked to lower rates of breast, endometrial and prostate cancer, among other health benefits.
In the Duke study, pregnant Agouti mice that ate a diet rich in genistein, an active ingredient in soy, gave birth to pups that stayed slimmer as adults. Mice that did not receive genistein in utero were much heavier as adults double the weight of their genistein-fed counterparts. Prenatal genistein also shifted the offspring's coat color from yellow to brown, demonstrating that a single nutrient can have a widespread systemic impact, said the researchers.
Genistein's effect occurred early in pregnancy, the equivalent of eight gestational days in humans. The Duke scientists said their results lend support to the "developmental origins of adult disease" hypothesis, in which an individual's long-term health is influenced by prenatal factors.
Results of the study, funded by the National Institute of Environmental Health Sciences and the National Cancer Institute, are published in the April 1, 2006, issue of the journal Environmental Health Perspectives.
"We are increasingly finding that our parent's and even our grandparent's nutritional status and environmental exposures can regulate our future risk of disease," said Randy Jirtle, Ph.D., professor of radiation oncology and senior author of the study. "In other words, it may not only be the hamburgers and fries we are eating, but also what our parents consumed or encountered in the environment that predisposes us to various conditions."