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 .
Reduced rates of skeletal remodeling are associated with increased bone mineral density during the development of peak skeletal mass.
Two related studies were conducted to assess the associations between markers of skeletal modeling and remodeling in healthy children . Members of monozygotic twin pairs , aged 6 - 14 , enrolled in a clinical trial of calcium supplementation  , were studied at the end of the period of supplementation and for 3 years thereafter . Supplemented children had significantly higher rates of gain in bone mineral density ( BMD ) ( + 3 % on average ) during the period of supplementation accompanied by significantly lower concentrations of serum osteocalcin ( OC , -15 % ) . During postsupplement follow-up , both differences in BMD and OC disappeared . Black females , age matched to the baseline ages of the white children , had significantly lower serum concentrations of both OC and tartrate-resistant acid phosphatase ( TRAP ) at all ages and higher BMDs . When stratified on serum TRAP concentrations , regardless of race , children with lower concentrations had significantly higher BMDs , and no racial differences were apparent . In regression models accounting for 70 - 80 % of the variability in BMD in children , body size and TRAP , but not race , remained significantly associated with BMD . The skeletal advantages seen with calcium supplementation and black race appear to be associated with reduced rates of skeletal turnover . Given that markers of turnover during growth reflect both skeletal modeling and remodeling , and there is no apparent advantage to reduced skeletal modeling , it seems probable that reduced remodeling is the factor that accounts for the increases in bone mass
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 .