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 .
Regional specificity of exercise and calcium during skeletal growth in girls: a randomized controlled trial.
Combining exercise with calcium supplementation may produce additive or multiplicative effects at loaded sites ; thus , we conducted a single blind , prospect i ve , r and omized controlled study in pre- and early-pubertal girls to test the following hypotheses . ( 1 ) At the loaded sites , exercise and calcium will produce greater benefits than exercise or calcium alone . ( 2 ) At non-loaded sites , exercise will have no benefit , whereas calcium with or without exercise will increase bone mass over that in exercise alone or no intervention . Sixty-six girls aged 8.8 + /- 0.1 years were r and omly assigned to one of four study groups : moderate-impact exercise with or without calcium or low-impact exercise with or without calcium . All participants exercised for 20 minutes , three times a week and received Ca-fortified ( 434 + /- 19 mg/day ) or non-fortified foods for 8.5 months . Analysis of covariance ( ANCOVA ) was used to determine interaction and main effects for  exercise and calcium  on bone mass after adjusting for baseline bone mineral content and growth in limb lengths . An exercise-calcium interaction was detected at the femur ( 7.1 % , p < 0.05 ) . In contrast , there was no  exercise-calcium interaction detected at the tibia-fibula ; however , there was a main effect of exercise : bone mineral content increased 3 % more in the exercise than non-exercise groups ( p < 0.05 ) . Bone mineral content increased 2 - 4 % more in the calcium-supplemented groups than the non-supplemented groups at the humerus ( 12.0 % vs. 9.8 % , respectively , p < 0.09 ) and radius-ulna ( 12.6 % vs. 8.6 % , respectively , p < 0.01 ) . In conclusion , greater gains in bone mass at loaded sites may be achieved when short bouts of moderate exercise are combined with increased dietary calcium , the former conferring region-specific effects and the latter producing generalized effects
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 .