Do Vitamin D Supplements Improve Cardiovascular Risk Factors?

In observational studies, lower vitamin D levels have been associated with higher cardiovascular risk, so some clinicians (including cardiologists in my community) are advising patients to take vitamin D supplements explicitly to lower cardiovascular risk. However, randomized trials with hard clinical endpoints to support this practice do not exist.

To determine whether vitamin D supplements favorably alter conventional cardiovascular risk factors, U.K. researchers randomized 305 postmenopausal women (mean age, 64) without known cardiovascular disease to receive vitamin D₃ supplements (either 400 or 1000 IU daily) or placebo. At baseline, mean 25-hydroxyvitamin D levels were 13.5 ng/mL. At 1 year, vitamin D levels had doubled in both supplem…