Women Benefit from Vitamin D Supplementation Mainly for Bone Health, Expert Says

   "Over the past several years many experts have been saying that we need to be testing women for vitamin D deficiency and we need to be treating them," noted Janet P. Pregler, MD, Professor of Clinical Medicine at the David Geffen School of Medicine at UCLA and Director of the Iris Cantor-UCLA Women’s Health Center. She gave an update on women's health issues at Internal Medicine 2011, the annual meeting of the American College of Physicians in San Diego.

   "And then the Institute of Medicine came out last year and said well, we think most women in the U.S. have adequate vitamin D. Many of us in general medicine are sort of perplexed. What do we do about this?"

   In an interview, Dr. Pregler explained that many of the studies citing benefits for supplements are cohort studies, which follow the characteristics of set groups, such as women who take vitamin supplements. "In women, cohort studies of vitamins have turned out to be not very accurate," she said. "In the 90s there was sort of a fad that we should take vitamin E to prevent heart disease. If you looked at cohort studies it was absolutely true that the women who were taking vitamin E were having fewer cardiovascular events."

   But they were also were otherwise healthy. And people who can afford vitamin supplements generally come from higher socioeconomic groups that have other health benefits, Dr. Pregler said.

   "When a large randomized trial was done, with over 40,000 women, there was absolutely no benefit, absolutely no difference.

   "And then we had the B vitamin and folate fad, which everyone remembers, 'oh we’re going to give B vitamin and folate and that's going to prevent cardiovascular disease and dementia'. Same story, randomized trials didn’t show it."

   According to Dr. Pregler, "the bottom line of where the research is going is that we’re not really finding benefits for vitamin D beyond bone health. We're looking at studies reviewing vitamin D and cardiovascular disease risk, hypertension and diabetes, and we’re not seeing that supplementing patients with vitamin D is helpful."