Understanding Vitamin D

Vitamin D helps your body absorb calcium, which keeps your bones strong. Some recent studies suggest that taking extra vitamin D can have other health benefits, but the evidence to date has been unclear.

Medical experts held a conference at NIH to take a closer look at the scientific evidence on vitamin D. They reported their conclusions in August 2008.

The strongest evidence suggesting other benefits from more vitamin D is for older people. Several clinical studies found that additional vitamin D can improve bone health and prevent falls in elderly men and post-menopausal women. The experts say they don’t yet have enough information to know if extra vitamin D might help people of other ages. More research is also needed to know if vitamin D can help prevent diseases like diabetes and cancer.

“It’s tempting to think that an essential nutrient is safe at any level—that if some is good, more is better—but that isn’t always true,” said Dr. Paul M. Coates, director of the NIH Office of Dietary Supplements. “There are potential harms associated with high levels of many nutrients.”

Scientific experts will continue to evaluate recent research to decide if current vitamin D recommendations should be revised. Talk to your doctor if you have questions about how much vitamin D you need.