August 25, 2009

Low-carb diets may impair vascular health

U.S. researchers say low-carbohydrate, high protein diets increased atherosclerosis in mice.

The study, published in the Proceedings of the National Academy of Sciences, found mice fed the 12 percent carbohydrate, 43 percent fat, 45 percent protein diets were more likely to show vascular damage then mice fed standard diets with 65 percent carbohydrate, 15 percent fat, 20 percent protein -- or even the Western diet diet of 43 percent carbohydrates 42 percent fat and 15 percent protein.

The researchers note the vascular damage took place in the animals fed the low-carb diet. However, their standard markers of cardiovascular risk such as cholesterol levels stayed the same.

It's very difficult to know in clinical studies how diets affect vascular health, senior study author Dr.Anthony Rosenzweig of Boston's Beth Israel Deaconess Medical Center and Harvard Medical School says in a statement.

We, therefore, tend to rely on easily measured serum markers such as cholesterol, which have been surprisingly reassuring in individuals on low-carbohydrate/high-protein diets, who do typically lose weight. But our research suggests that, at least in animals, these diets could be having adverse cardiovascular effects that are not reflected in simple serum markers.