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 .
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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 .
Effect of a calcium and exercise intervention on the bone mineral status of 16-18-y-old adolescent girls.
BACKGROUND Osteoporosis may be prevented or delayed by maximizing peak bone mass through diet modification and physical activity during adolescence . OBJECTIVE We studied whether increases in calcium intake and physical activity effectively increase the bone mineral status of adolescent girls aged 16 - 18 y. DESIGN We conducted a 15.5-mo study of calcium supplementation ( 1000 mg Ca/d as carbonate ) in 144 adolescent girls aged 17.3 + /- 0.3 y ( + /- SD ) . The subjects were r and omly allocated to an exercise ( three 45-min exercise-to-music classes/wk during term time ) or nonexercise group . Dual-energy X-ray absorptiometry of the whole body , spine , forearm , and hip was performed before and after intervention . RESULTS The mean ( + /- SD ) percentage of subjects compliant with supplement taking was 70 + /- 27 % and with exercise class attendance was 36 + /- 25 % . Baseline calcium intake was 938 + /- 411 mg/d . Calcium supplementation significantly increased size-adjusted bone mineral content . The effect was stronger in subjects with good compliance ( percentage difference + /- SE ) : whole body , 0.8 + /- 0.3 % ( P < or = 0.01 ) ; lumbar spine , 1.9 + /- 0.5 % ( P < or = 0.001 ) ; ultradistal radius , 1.3 + /- 0.6 % ( P < or = 0.05 ) ; total hip , 2.7 + /- 0.6 % ( P < or = 0.001 ) ; femoral neck , 2.2 + /- 0.7 % ( P < or = 0.001 ) ; trochanter , 4.8 + /- 0.9 % ( P < or = 0.001 ) . Attendance at > 50 % of the exercise sessions was significant at the total hip ( 1.4 + /- 0.7 % ; P < or = 0.05 ) and trochanter ( 2.6 + /- 1.2 % ; P < or = 0.05 ) . CONCLUSIONS Calcium supplementation and exercise enhanced bone mineral status in adolescent girls . Whether this is a lasting benefit , leading to the optimization of peak bone mass and a reduction in fracture risk , needs to be determined
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 .