Tufts Nutrition

Limiting saturated fat could help people whose genetic makeup increases their chance of being obese. Researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts identified 63 gene variants related to obesity and used them to calculate an obesity risk score for more than 2,800 white American men and women enrolled in two large studies on preventing heart disease.

Those with a higher genetic risk score who consumed more of their calories as saturated fat were more likely to have a higher Body Mass Index (BMI), the ratio of body weight to height.

“We already know there are certain genes that interact with dietary fat and affect BMI,” says senior author José M. Ordovás, Ph.D., director of the Nutrition and Genomics Laboratory at the HNRCA and a professor at the Friedman School. “In the current study, we analyzed dozens of variants of those genes and other genes frequently associated with obesity risk and saw that while total fat intake was related to higher BMI, people who were genetically predisposed to obesity and ate the most saturated fat had the highest BMIs.”

As for why this would be the case, Ordovás says some research suggests that saturated fat might interfere with activity in the part of the brain that lets us know we’re full. He said more research is needed to know whether those findings would apply to gene function. The study appeared in the Journal of the Academy of Nutrition and Dietetics.