Calcium Alone Won't End Hip Fracture Risk

People, especially the elderly, may reach for calcium supplements in hopes of protecting themselves against bone fractures in case of a fall. But a recent analysis of several studies found no reduction in risk of hip fracture with calcium supplementation.

The analysis was supported in part by the Agricultural Research Service (ARS). It comes on the heels of another ARS-funded study suggesting that today's current recommended amount of dietary calcium for American adults may be greater than actually needed. ARS is a scientific research agency of the U.S. Department of Agriculture.

Bess Dawson-Hughes and colleagues in academia and medicine researched calcium intake studies that had been published between January 1960 and December 2006. They also systematically searched information from biomedical databases, reference lists and abstracts for the study review.

Dawson-Hughes is director of the Bone Metabolism Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts. The analysis was published in the American Journal of Clinical Nutrition.

Among the studies that met the researchers' screening criteria, seven included a total of 170,991 women with nearly 3,000 hip fractures. Five of the studies included a total of 68,606 men with 214 hip fractures. Pooled results from those studies suggest that calcium intake is not appreciably associated with hip fracture risk in women or men. That means the researchers did not find that a higher calcium intake reduced the incidence of hip fractures.

Hip fractures are the most frequent and severe fractures among the elderly, and experts estimate the average cost of care at $29,000 per patient. Increased calcium intake is still commonly recommended as a single fracture prevention strategy, although considerable uncertainty exists regarding optimal intakes of calcium, the authors wrote. For example, for adults over age 50, the recommended calcium intake is 700 milligrams (mg) daily in the United Kingdom, but 1,200 mg daily in the United States.

The authors concluded that the findings do not support an overall benefit from greater-than-average calcium intake.

Future studies of fracture prevention should focus on the best combination of calcium plus vitamin D, rather than on calcium supplementation alone, according to authors.