CONCLUSIONS Dietary calcium intake is not associated with risk of fracture , and there is no clinical trial evidence that increasing calcium intake from dietary sources prevents fractures .
OBJECTIVE To examine the evidence underpinning recommendations to increase calcium intake through dietary sources or calcium supplements to prevent fractures .
Long-term effects of calcium supplementation on bone loss and fractures in postmenopausal women: a randomized controlled trial.
PURPOSE To determine the long-term effects of calcium supplements or placebo on bone density in healthy women at least 3 years postmenopause . PATIENTS AND METHODS Eighty-six women from our previously reported 2-year study agreed to continue on their double-blind treatment allocation ( 1 g elemental calcium or placebo ) for a further 2 years , with 78 women ( 40 on placebo ) reaching the 4-year end point .  Median ( interquartile range ) dietary calcium intakes for the whole group were 700 mg ( range 540 to 910 ) per day at baseline , 670 mg ( range 480 to 890 ) per day at 2 years , and 640 mg ( range 460 to 880 ) per day at 4 years . The bone mineral density ( BMD ) of the total body , lumbar spine , and proximal femur was measured every 6 months by dual-energy , x-ray absorptiometry . RESULTS There was a sustained reduction in the rate of loss of total body BMD in the calcium group throughout the 4-year study period ( P = 0.002 ) , and bone loss was significantly less in the calcium-treated subjects in years 2 through 4 also ( difference between groups 0.25 % + /- 0.11 % per year , P = 0.02 ) . In the lumbar spine , bone loss was reduced in the calcium group in year 1 ( P = 0.004 ) , but not subsequently . There was , however , a significant treatment effect at this site over the whole 4-year period ( P = 0.03 ) . In the proximal femur , the benefit from calcium treatment also tended to be greater in the first year and was significant over the 4-year study period in the femoral neck ( P = 0.03 ) and the trochanter ( P = 0.01 ) . Nine symptomatic fractures occurred in 7 subjects in the placebo group and 2 fractures in 2 subjects receiving calcium ( P = 0.037 ) . CONCLUSIONS Calcium supplementation produces a sustained reduction in the rate of loss of total body BMD in healthy postmenopausal women
CONCLUSIONS Dietary calcium intake is not associated with risk of fracture , and there is no clinical trial evidence that increasing calcium intake from dietary sources prevents fractures .
OBJECTIVE To examine the evidence underpinning recommendations to increase calcium intake through dietary sources or calcium supplements to prevent fractures .