NEW HAVEN, Conn.The offspring of obese mothers consuming a high-fat diet during pregnancy are at a higher risk than the children of healthy-weight mothers for lifelong obesity, and related metabolic disorders, according to a new study published in the journal Cell.
Yale researchers, along with researchers at University of Cologne, studied the effects of a mother's high-fat diet on offspring to identify the key point in pregnancy when maternal nutrition has the most impact on an offspring's metabolic health.
Researchers conducted the study using a mouse model of metabolic programming. They found that mouse mothers fed a high-fat diet during breastfeeding had offspring with abnormal neuronal connections in the hypothalamusa key brain region that regulates metabolismas well as altered insulin signaling in this brain circuit. As a result, the offspring remained overweight and had abnormalities in glucose metabolism throughout life.
"Our study suggests that expecting mothers can have major impact on the long-term metabolic health of their children by properly controlling nutrition during this critical developmental period of the offspring," said the study's co-lead author Tamas Horvath, the Jean and David W. Wallace professor of biomedical research and chair of comparative medicine at Yale School of Medicine.
Because of developmental differences between speciesneural circuits in the hypothalamus continue to develop after birth in mice, but are fully developed before birth in humansthe findings suggest that the third trimester of pregnancy in humans is the most critical period. That's when a mother's diet will most likely have long-lasting effects on her offspring's health, according to the researchers.
"Mothers can control or even reverse their offspring's predisposition to obesity and resulting diseases by altering their food intake," said Horvath. "Because gestational diabetes frequently manifests during the third trimester, the results could inform more intense screening of mothers for alterations in glucose metabolism."
Obesity has been a growing issue not only in the United States, but on a globally as wellobesity has tripled in the developing world. Among U.S. children, 5% are considered severely obese. There have been many efforts to reduce obesity rates and lower the risk of obesity, including an effort by the food and beverage industry to trim calories from the American diet. In fact, 16 of the nations leading food and beverage companies sold 6.4 trillion fewer calories in the United States in 2012 than they did in 2007.