Calcium prevents fractures in elderly women

Calcium supplementation is effective in preventing fractures in elderly women, only if women are compliant. Increasing dietary calcium has been proposed as a population-based public health intervention to prevent fractures due to the bone-thinning disease osteoporosis. Researchers from the University of Western Australia examined whether calcium supplementation decreases fracture risk in elderly women. A total of 1460 women with an average age of 75 years were randomly assigned to receive 600 mg calcium carbonate twice daily or placebo. Overall, 1228 women completed the five years long study. It was found that a total of 236 women (16 percent) sustained 297 osteoporotic fractures. Some analyses failed to show a protective effect of calcium on fracture risk. However, in an analysis restricted to the 830 patients (57 percent) who took at least 80 percent of their calcium tablets, a reduction of 34 percent in the risk of fracture at any site was apparent in the calcium arm. Calcium-treated patients showed significant improvements in measurements of the heel, femoral neck, and whole-body dual x-ray absorptiometry data. Bone strength was also improved in patients treated with calcium compared to placebo-treated patients. While a total of 92,000 adverse events were recorded, only constipation was more common in calcium-treated patients compared with placebo-treated patients (13 percent versus 9 percent).