American scientists say studies in rats suggest that eating a high fat diet during pregnancy raises levels of triglycerides in the blood which boost the production of permanent neurons in the fetal brain that increases the desire for fat in childhood.

Scientists from the Rockefeller University in New York said in the Journal of Neuroscience that it was a major step toward understanding how new brain cells were "programmed" in the fetus.

Senior researcher Sarah Leibowitz said she believed similar mechanisms to those seen in the rats operated in humans and it could help explain the increased rates of childhood obesity during the past 30 years.

"We've shown that short-term exposure to a high-fat diet in utero produced permanent neurons in the fetal brain that later increase the appetite for fat," she said.

Leibowitz said that when they looked at the effects of feeding pregnant rats high fat foods for two weeks instead of a balanced diet with only moderate amounts of fat, they found that their offspring ate more fat and weighed more throughout life.

From the November 24, 2008, Prepared Foods e-Flash