Consuming at least 1000 milligrams of calcium a day can help prevent bone loss in postmenopausal women living in regions that do not get strong sunlight year round, suggests research in the Journal of Clinical Endocrinology and Metabolism.
Sunlight helps the skin synthesize vitamin D, which in turn helps the body to absorb calcium.
But during the winter months when the skin is often unexposed to sunlight, vitamin D levels can fall, and calcium stored in bone may be depleted to make up for inadequate dietary calcium intake. The result can be reduced bone density and increased risk of fractures. The study randomly divided 60 elderly postmenopausal women into three groups. Subjects were from rural areas in Maine and did not have the bone-thinning disease osteoporosis. The women who drank milk sustained minimal loss while the women who took supplements suffered no bone loss and showed a significant increase in bone mineral density.