Calcium and Vitamin D: Do They Benefit Women?

Postmenopausal women consistently taking calcium and vitamin D supplements may have the best shot at preserving bone mass and preventing fractures.

New research from the calcium and vitamin D supplementation arm of the Women’s Health Initiative (WHI) reveals only small benefits for women taking the supplements. It shows women taking a daily dose of 1,000 milligrams of elemental calcium as calcium carbonate combined with 400 international units (IUs) of vitamin D have a 1-percent higher hipbone density than those taking a placebo.

The benefits increased greatly in certain subgroups. Researchers found women most compliant about taking the supplements had a 29-percent decrease in hip fractures. Women ages 60 and older had 21-percent fewer broken hips. The study assessed 36,000 participants.

“The value of a study this large is that it does shows, even if only on a small scale, that the intervention can be effective to lower the risk of osteoporosis within two to three years,” says Rebecca Jackson, lead author and The Ohio State University Medical Center’s principal investigator for WHI. “Any supplementation of this kind is potentially beneficial, particularly in women over 60 years old. That’s a huge finding.”

Despite the benefits in preserving bone mass and preventing hip fractures, the study reveals calcium and vitamin D supplements do not prevent other types of fractures or colorectal cancer.

Researchers also found overall, the supplements were well tolerated but were associated with an increased risk of kidney stones.

SOURCE: The New England Journal of Medicine, 2006;354:669-683