High-fat diet during pregnancy produces permanent changes in the offspring's brain that lead to increased appetite and obesity early in life, a study in rats has shown.  The surprising new research by Rockefeller University scientists has been reported in the Nov. 12 issue of the Journal of Neuroscience.

The research provides a key step toward understanding mechanisms of fetal programming involving the production of new brain cells that may help explain the increased prevalence of childhood obesity during the last 30 years.

We've shown that short-term exposure to a high-fat diet in utero produces permanent neurons in the fetal brain that later increase the appetite for fat," says senior author Sarah F. Leibowitz, who directs the Laboratory of Behavioral Neurobiology at Rockefeller.

This work provides the first evidence for a fetal program that links high levels of fats circulating in the mother's blood during pregnancy to the overeating and increased weight gain of offspring after weaning," the expert added.

Research in adult animals by Leibowitz and others has shown that circulating triglycerides stimulate brain chemicals known as orexigenic peptides, which in turn spur the animals to eat more. Scientists also have shown that obese and diabetic mothers produce heavier children and that exposure to fat-rich foods early in life leads to obesity in adulthood.

These studies suggested that food intake and body weight may be programmed during fetal development. But little was known about the mechanism underlying this programming.