Calcium supplements  increased BMD by 0.7 - 1.8 % at all five skeletal sites at one , two , and over two and a half years , but the size of the increase in BMD at later time points was similar to the increase at one year .
Increasing calcium intake from dietary sources or by taking calcium supplements produces small non-progressive increases in BMD , which are unlikely to lead to a clinical ly significant reduction in risk of fracture
OBJECTIVE To determine whether increasing calcium intake from dietary sources affects  bone mineral density ( BMD ) and , if so , whether the effects are similar to those of calcium supplements .
A controlled trial of the effect of calcium supplementation on bone density in postmenopausal women.
Background . The effectiveness of calcium in retarding bone loss in older postmenopausal women is unclear . Earlier work suggested that the women who were most likely to benefit from calcium supplementation were those with low calcium intakes . Methods . We undertook a double-blind , placebo-controlled , r and omized trial to determine the effect of calcium on bone loss from the spine , femoral neck , and radius in 301 healthy postmenopausal women , half of whom had a calcium intake lower than 400 mg per day and half an intake of 400 to 650 mg per day . The women received placebo or either calcium carbonate or calcium citrate malate ( 500 mg of calcium per day ) for two years . Results . In women who had undergone menopause five or fewer years earlier , bone loss from the spine was rapid and was not affected by supplementation with calcium . Among the women who had been postmenopausal for six years or more and who were given placebo , bone loss was less rapid in the group with the higher dietary calcium intake . In those with the lower calcium intake , calcium citrate malate prevented bone loss during the two years of the study ; its effect was significantly different from that of placebo ( P less than 0.05 ) at the femoral neck ( mean change in bone density [ + /- SE ] , 0.87 + /- 1.01 percent vs. -2.11 + /- 0.93 percent ) , radius ( 1.05 + /- 0.75 percent vs. -2.33 + /- 0.72 percent ) , and spine ( -0.38 + /- 0.82 percent vs. -2.85 + /- 0.77 percent ) . Calcium carbonate maintained bone density at the femoral neck ( mean change in bone density , 0.08 + /- 0.98 percent ) and radius ( 0.24 + /- 0.70 percent ) but not the spine ( -2.54 + /- 0.85 percent ) . Among the women who had been postmenopausal for six years or more and who had the higher calcium intake , those in all three treatment groups maintained bone density at the hip and radius and lost bone from the spine . Conclusions . Healthy older postmenopausal women with a daily calcium intake of less than 400 mg can significantly reduce bone loss by increasing their calcium intake to 800 mg per day . At the dose we tested , supplementation with calcium citrate malate was more effective than supplementation with calcium carbonate
Calcium supplements  increased BMD by 0.7 - 1.8 % at all five skeletal sites at one , two , and over two and a half years , but the size of the increase in BMD at later time points was similar to the increase at one year .
Increasing calcium intake from dietary sources or by taking calcium supplements produces small non-progressive increases in BMD , which are unlikely to lead to a clinical ly significant reduction in risk of fracture
OBJECTIVE To determine whether increasing calcium intake from dietary sources affects  bone mineral density ( BMD ) and , if so , whether the effects are similar to those of calcium supplements .