Monday, August 31, 2009

Low-carb diet linked to plaque buildup

Low-carbohydrate diets have helped some people lose weight quickly, but the diets’ long-term effects on cardiovascular health have been uncertain.

Cardiologist Dr. Anthony Rosenzweig of Beth Israel Deaconess Medical Center and his colleagues tested three diets in mice genetically engineered for studying human heart disease. The mice were fed standard high-carb mouse chow, a typical Western diet with moderate amounts of carbs and protein, and a low carb-high protein diet.

After 12 weeks, mice on the low carb-high protein diet gained weight, but less than the other mice. There were no differences in cholesterol levels among the mice, but the mice on the low carb-high protein diet accumulated more plaque in their coronary arteries, called atherosclerosis, than mice on the other two diets. They also had lower levels of cells needed to repair and regrow new blood vessels, which the authors say may be linked to their arteries’ plaque buildup.

BOTTOM LINE: Mice fed a low-carbohydrate, high-protein diet accumulated more plaque in their coronary arteries and had fewer cells needed for healthy blood vessels than mice fed other diets.

CAUTIONS: Similar changes might not occur in humans.

WHAT’S NEXT: Better ways to detect cells that repair blood vessels will help assess how they might be affected by diet.

WHERE TO FIND IT: Proceedings of the National Academy of Sciences, Aug. 24