Calcium, Vitamin D: Helpful for Some Women

Take calcium and vitamin D after menopause? Yes, it just might help, says a new study. An analysis from the major Women’s Health Initiative (WHI) trial seems to indicate that—for women taking hormones after menopause—calcium and vitamin D are beneficial. The analysis was just published online in Menopause, the journal of The North American Menopause Society.

Among the nearly 30, 000 postmenopausal women in the hormone trial, some 8, 000 took supplemental calcium and vitamin D, and some 8, 000 took look-alike placebos. The researchers looked at how the rates of hip fracture differed among women who took hormones and supplements, those who took hormones alone, and those who took neither.

Women using both therapies had much greater protection against hip fractures than with either therapy alone. Taking supplements alone wasn’t significantly better than taking no supplements and no hormones. The benefit of hormone therapy was strong in women who had a total calcium intake (supplements plus diet) greater than 1, 200 mg/day. Similarly, the benefit was strong in women who had higher intakes of vitamin D, but the individual effect of each one could not be determined because the two supplements were given together.

These results that women taking postmenopausal hormone therapy should also take supplemental calcium and vitamin D differ from the recommendation of the U.S. Preventive Services Task Force (USPSTF), made earlier this year. USPSTF stated there was no basis for recommending calcium and vitamin D supplements to prevent fractures. This study could make people take a second look.

John Robbins, M.D., study author and professor of medicine at the University of California, Davis told OTW, “I hope patients who are taking estrogens for any reason will start taking vitamin D and calcium with them in reasonable, not excessive, amounts.”

Asked about the controversies that remain, Dr. Robbins said, “There are obviously lots. We have little idea as to how much calcium and vitamin D are enough. It would also be important to know if they should be given with what are now the more standard osteoporosis treatments.”

Asked about the future of related research, Dr. Robbins is not positive. “I fear we are not likely to have the power to answer many questions about calcium supplementation. WHI had thousands of women. It was very expensive and is unlikely that this type of large trial will happen again. There are a few ongoing vitamin D trials. They are low budget, by mail, trials and may not give us any better answers. It would be great to look at therapies for osteoporosis such as alendronate with and without vitamin D and calcium supplementation but now that it is off patent I doubt it will happen.”