Vitamin D & cancer

Vitamin D and calcium seemed to cut the risk of cancer in a study that was designed to see if the supplements could prevent bone fractures.

Researchers gave 1,179 Nebraska women over age 55 daily doses of vitamin D (1,100 International Units) plus calcium (1,400 to 1,500 milligrams), calcium alone, or a placebo. After four years, cancers (most often breast) were diagnosed in 7 percent of the women who took the placebo, 4 percent of the women who took calcium alone, and just 2 percent of the women who took both vitamin D and calcium.

What to do: This study had too few cancers to be the final word on whether vitamin D prevents cancer. But it's worth taking 1,000 IU a day (and 1,200 mg of calcium) to protect your bones.

The only other trial that tested vitamin D on cancer--the Women's Health Initiative--found no lower risk of colorectal cancer. But it used a much lower dose (400 IU a day). However, in both this study and the Women's Health Initiative, women who started the study with higher blood levels of vitamin D had a lower risk of cancer.

Am. J. C/in. Nutr: 85: 1586, 2007.

COPYRIGHT 2007 Center for Science in the Public Interest
COPYRIGHT 2008 Gale, Cengage Learning