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 .
Milk consumption and bone mineral content in Chinese adolescent girls.
A cross-sectional study of a r and om sample of 649 girls , aged 12 - 14 years ( mean + /- SD : 12.9 + /- 0.6 years ) , in the Beijing area examined the relationship between diet and bone mineral status . Food and nutrient intakes over the past year were estimated by means of a semiquantitative food frequency question naire . Bone mineral content ( BMC ) and bone width ( BW ) at the distal one-third and one-tenth radius and ulna were measured by single-photon absorptiometry . Results showed Beijing pubertal girls had a low mean milk consumption  ( fresh and powdered milk , vitamin D-fortified milk , and yogurt ) at 50 g/day ( 95 % confidence interval [ CI ] 44 - 55 g/day whereas one-third consumed no milk at all . Mean calcium intake was 356 + /- 97 mg/day of which only 21 % was provided by milk and milk products .  Milk intake varied by region ( rural , suburban , and urban : 9 , 36 , and 83 g/day , respectively , p < 0.0005 ) as did the proportion of milk consumers in the three areas ( 30 % , 64 % , and 91 % , p < 0.0005 ) . Bone mineral density ( BMD ) at the distal one-third and one-tenth radius and one-tenth ulna was positively associated with milk consumption ( p < 0.05 ) . Multiple regression analysis of BMC on foods and nutrients as well as confounding factors , including weight , bone age , Tanner stage , and School Physical Activity Score ( SPAS ) , showed that milk intake was the only dietary factor included in the models for BMC at the four bone sites measured . The model explained 54%-65 % of the variation in BMC , and milk alone accounted for up to 3.2 % of the variation . Milk was the only food group with significant partial correlation with BMC . SPAS , weight , bone age , and Tanner stage each accounted for a smaller variation in BMC ( < 1.8 % ) . The results indicate that milk ( presumably as an integrated source of nutrients ) had a beneficial effect on bone mass of Beijing pubertal girls and was a better nutritional determinant of BMC than intake of any milk nutrient alone . Promotion of milk consumption should be considered for achieving optimal bone mass in this population group
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 .