Researchers from Tufts University and Tufts Medical Center have found that taking vitamin D3 supplements has no effect on serum cholesterol. Their randomized controlled trial, published recently in the American Journal of Clinical Nutrition, does not support results from observational studies that found an association between serum levels of vitamin D and LDL or HDL cholesterol concentrations.
One hundred and twenty-seven participants were given either 4,000 International Units of vitamin D3 a day or a placebo for 24 weeks. At the end of the study period, the supplement group’s serum vitamin D levels were higher, but their cholesterol profiles were not significantly different. There was also no change in how much cholesterol they absorbed from food or how much was manufactured by the body. “Our hypothesis was that raising vitamin D levels would improve cholesterol concentrations by decreasing cholesterol absorption,” says Alice H. Lichtenstein, executive editor of Tufts Health & Nutrition Letter and the study’s senior author. “In fact, our hypothesis was rejected.”