Washington, Aug 24 - Researchers have found why low levels of vitamin D are known to nearly double the risk of cardiovascular disease in diabetics.

Researchers at Washington University School of Medicine in St. Louis (WUSM-SL) have found that diabetics deficient in vitamin D can't process cholesterol normally, so it builds up in their blood vessels, increasing the risk of heart attack and stroke.

The new research has identified a mechanism linking low vitamin D levels to heart disease risk and may lead to ways to fix the problem, simply by increasing levels of vitamin D.

'Vitamin D inhibits the uptake of cholesterol by cells called macrophages,' said principal investigator Carlos Bernal-Mizrachi, Washington University endocrinologist.

'When people are deficient in vitamin D, the macrophage cells eat more cholesterol, and they can't get rid of it.