Analysis questions calcium's benefits for fractures

Placing all the eggs in one basket and relying on calcium supplements alone to protect against fractures in old age may be inefficient, according to a new review by Harvard researchers.

No benefits were calculated for calcium supplements and the risk of hip fracture, according to the meta-analysis of 12 prospective cohort studies and nine clinical trials, published in this month's issue of the American Journal of Clinical Nutrition.

The authors, led by Heike Bischoff-Ferrari from Harvard School of Public Health, report no statistically significant benefit for 300 mg per day calcium intakes from seven prospective cohort studies involving 170 991 women and with 2954 documented hip fractures, and five prospective cohort studies involving 68 606 men and with 214 documented hip fractures.

Moreover, clinical trials involving supplementation with 800 to 1600 mg per day of calcium did not show any benefits with respect to non-vertebral fractures and hip fracture, compared to placebo.

In an accompanying editorial, Jeri Nieves and Robert Lindsay from New York's Columbia University and the Clinical Research Center, Helen Hayes Hospital wrote: "Perhaps these data suggest that calcium supplementation, to be effective, requires the addition of vitamin D supplementation.

"Studies of calcium without regard to vitamin D status may then lead to erroneous conclusions… Those authors discussed the possibility that the efficacy of calcium intake may be enhanced by additional vitamin D.

"A well-rounded diet is important, and evaluation of one element or vitamin does not give the whole story," concluded Nieves and Lindsay.

"Bone is not just calcium, and calcium does not function in isolation."

Bonnie - while we have discussed at length that one cannot rely on meta-analysis, we published this study because of the comments made by the researchers (we put in bold). They are finally starting to get it! What have we said for years? Bone is not just calcium. It is complex matrix of nutrients. This is why we have always said that it is not about how much calcium you get, but how well it is absorbed. Additionally, one must have adequate vitamin D, magnesium, and low inflammation to maintain healthy bone.