Low-carb diet damages arteries, study shows

Low-carbohydrate diets may damage arteries and increase the risk of heart attacks, research suggests. Scientists believe cutting carbs on Atkins-style diets impairs the regrowth and repair of blood vessels.

The discovery was made by a team whose leader was on a low-carb diet until he saw the results. Researchers used mice to test three diets. One group of mice was fed a basic mouse diet. A second was fed a "Western" diet of 43 per cent carbohydrate, 42 per cent fat, 15 per cent protein and 0.15 per cent cholesterol. A third was fed only 12 per cent carbohydrate and 43 per cent fat, 45 per cent protein and 0.15 per cent cholesterol.

Mice on the low-carb diet gained 28 per cent less weight than those on the Western diet but they suffered more atherosclerosis – the build-up of deposits that narrow arteries. Levels of cholesterol, triglyceride blood fats and inflammation markers linked to atherosclerosis could not account for the findings, but the production of endothelial progenitor cells in mice on the low-carb diet was found to have dropped by 40 per cent after two weeks. These cells help repair and grow blood vessels.

The findings suggest factors other than fat and cholesterol may be important to heart health. Anthony Rosenzweig, from the Beth Israel Deaconess Medical Centre in Boston, said: "Our research suggests ... these diets could be having adverse cardiovascular effects that are not reflected in simple serum markers [like cholesterol]." The findings are in Proceedings of the National Academy of Sciences.