Vitamin D may not protect black women from bone loss

The question: Vitamin D helps the body absorb calcium, which in turn helps reduce the loss of bone density in older women. Since black women generally have lower levels of vitamin D than white women, presumably because they absorb less from the sun through the skin, might vitamin D supplements slow their bone loss?

This study randomly assigned 208 black, post-menopausal women to take either vitamin D supplements or a placebo daily. The supplement group took 800 international units of vitamin D for two years, then 2,000 IU for a year. All women also took calcium supplements to ensure they took in 1,200 to 1,500 milligrams daily. After three years, bone density overall had declined about the same amount among women who did and did not take vitamin D.

Who may be affected by these findings? Older black women. About 40 percent of black women over 50 have low bone density, making them more susceptible to the brittle bones and fracture risk of osteoporosis.

Caveats: Whether the findings apply to women of other races was not determined. The study did not find that vitamin D had no health value but rather that it may not aid in reducing the risk of bone fragility and fracture.

Find this study: July 25 issue of the Archives of Internal Medicine; abstract available online at www.archinternmed.com.

Learn more about bone loss and osteoporosis at www.cdc.gov (search for “bone health”) and www.nof.org.