Science / Medicine : Exercising While Dieting Helps

Getting some exercise while going on a low-fat diet can help people lose weight while keeping up their levels of the so-called good cholesterol that protects hearts, Stanford University researchers reported last week in the New England Journal of Medicine. While low-fat diets are widely recommended, some experts question whether the benefits of losing weight might be canceled out by a fall in high-density lipoprotein cholesterol, HDL, the good cholesterol.

The study of 264 men and women found that if people walk or jog while dieting, they can increase their HDL. But if they diet without exercising, they may reduce their levels of HDL, potentially increasing their risk of heart attacks.

Physician Peter D. Wood and his colleagues found that women who dieted but did not exercise reduced their HDL levels by 10%, but those who did both raised it 1%. Men who only dieted had a 2% rise in HDL, while those who dieted and exercised had a 13% increase. Exercise and diet together reduced both sexes’ risk of heart disease by 35%.