There was no effect of calcium supplementation  on femoral neck or lumbar spine BMD .
There was no evidence of effect modification by baseline calcium intake , sex , ethnicity , physical activity or pubertal stage .
While there is a small effect of calcium supplementation in the upper limb , the increase in BMD which results is unlikely to result in a clinical ly significant decrease in fracture risk .
The results do not support the use of calcium supplementation  in healthy children as a public health intervention .
These results can not be extrapolated to children with medical conditions affecting bone metabolism
BACKGROUND Clinical trials have shown that  calcium supplementation in children can increase  bone mineral density ( BMD ) although this effect may not be maintained .
There has been no quantitative systematic review of this intervention .
To determine the effectiveness of calcium supplementation for improving BMD  in children .
.
To determine if any effect varies by sex , pubertal stage , ethnicity or level of physical activity , and if any effect persists after supplementation is ceased .
Treatment with intermittent calcitriol and calcium reduces bone loss after renal transplantation.
BACKGROUND Bone loss occurs during the first 6 months after renal transplantation ( RT ) , and corticosteroid therapy plays an important role . Although calcium plus vitamin D administration prevents corticosteroid-induced osteoporosis , its use in RT recipients is limited by the risk of hypercalcemia . METHODS This double-blind , r and omized , and controlled prospect i ve intervention trial examined the effect of intermittent calcitriol ( 0.5 microg/48 h ) during the first 3 months after RT , plus oral calcium supplementation ( 0.5 g/day ) during 1 year with calcium supplementation alone . The primary outcome measure was the change in bone mineral density ( BMD ) at 3 and 12 months after RT ; we also explored whether the effect of calcitriol on BMD was different among vitamin D receptor ( VDR ) genotypes ( BsmI ) . Forty-five recipients were r and omized to calcitriol therapy ( CT ) and 41 were r and omized to placebo ( PL ) . RESULTS Both groups had a similar degree of pre-existing hyperparathyroidism ( 197 + /- 229 vs. 191 + /- 183 pg/mL ) , but a more pronounced decrease of parathyroid hormone ( PTH ) levels after RT was observed in CT patients ( at 3 months : 61.4 + /- 42.2 vs. 85.7 + /- 53.1 pg/mL , P= 0.02 ; at 12 months : 67.3 + /- 33.7 vs. 82.6 + /- 37 pg/mL ; P= 0.08 ) . CT patients preserved their BMD at the total hip significantly better than those on PL ( 3 months : 0.04 + /- 3.3 vs. -1.93 + /- 3.2 % , P= 0.01 ; 12 months : 0.32 + /- 4.8 vs. -2.17 + /- 4.4 % , P= 0.03 ) ; significant differences were noted at the intertrochanter , trochanter , and Ward 's triangle . Differences did not reach significance at the femoral neck . Two CT patients ( 4.4 % ) and 4 PL patients ( 9.8 % ) developed a hypercalcemic episode during the first 3 months after RT . The effect of  CT  on BMD at 3 months was more prominent in recipients with the at-risk allele of the VDR gene ( P= 0.03 ) . CONCLUSION Therapy with low-dose calcium supplements during 1 year , plus intermittent calcitriol for 3 months after RT , is safe , decreases PTH levels more rapidly , and prevents bone loss at the proximal femur ; a more pronounced effect is seen in recipients with at least one at-risk allele of the VDR genotype
There was no effect of calcium supplementation  on femoral neck or lumbar spine BMD .
There was no evidence of effect modification by baseline calcium intake , sex , ethnicity , physical activity or pubertal stage .
While there is a small effect of calcium supplementation in the upper limb , the increase in BMD which results is unlikely to result in a clinical ly significant decrease in fracture risk .
The results do not support the use of calcium supplementation  in healthy children as a public health intervention .
These results can not be extrapolated to children with medical conditions affecting bone metabolism
BACKGROUND Clinical trials have shown that  calcium supplementation in children can increase  bone mineral density ( BMD ) although this effect may not be maintained .
There has been no quantitative systematic review of this intervention .
To determine the effectiveness of calcium supplementation for improving BMD  in children .
.
To determine if any effect varies by sex , pubertal stage , ethnicity or level of physical activity , and if any effect persists after supplementation is ceased .