Following low-fat diets containing less than 30% of calories from fat have helped many obese and overweight people shed pounds that hamper their health. But reducing fat in the diet may lower HDL, the 'good' cholesterol that is often associated with heart health. In a recent study published in the Journal of the American Dietetic Association, researchers pinpoint the introduction of simple sugars into the diet as the possible cause.

Fifty-five overweight and obese women who were following the American Health Association Step 1 Diet (a diet designed as part of a treatment of high cholesterol) recorded their food intake and had their cholesterol levels and weight checked throughout the course of the 10-week study.

After the women began the diet, their percentage of calories from total fat, saturated fat and dietary cholesterol decreased, whereas their percentage of calories from carbohydrates, both complex and simple, increased. The women lost small but significant amounts of body weight and reduced overall cholesterol and LDL cholesterol (the 'bad' cholesterol that aids in the formation of plaque on the artery walls). However, the women also reduced HDL cholesterol (the 'good' cholesterol in the body that protects the arteries from hardening). The researchers theorize that substituting sugar for fat in the diet could have contributed to the reduction in HDL.

If you're following a low-fat diet designed to reduce weight and cholesterol, monitor your consumption of simple sugars such as candy, soft drinks, cookies, cakes and white breads and pastas. Although those products may be technically low in fat, their high sugar content may add calories to your diet. Instead, consume whole-grain foods such as breads and pastas made with stone-ground whole-wheat flour, fruits and vegetables.

Related information: About cholesterol | Food choices for weight management

Sources:  Bunyard LB, Dennis KE, Nicklas BJ. Dietary intake and changes in lipoprotein lipids in obese, postmenopausal women placed on an American Heart Association Step 1 diet. Journal of the American Dietetic Association 2002 Jan;102(1):52-7.