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 .
Bone mass and density response to a 12-month trial of calcium and vitamin D supplement in preadolescent girls.
BACKGROUND Maximal bone acquisition in adolescent girls through dietary and lifestyle practice s is advocated to prevent or minimize the development of osteoporosis and its associated complications in later life . Longitudinal investigations of bone acquisition in children and adolescents have utilized areal bone mineral density ( BMD , mg/cm(2 ) ) as a measure of bone mass and strength . Peripheral quantitative computed tomography ( pQCT ) , which provides a three-dimensional display of data , separate analyses of bone compartments , and bone mass in terms of volumetric BMD ( vBMD , mg/cm(3 ) ) , has recently been introduced for clinical use . OBJECTIVE To assess the impact of a 12-month daily calcium supplement on total and trabecular bone acquisition as measured by pQCT in preadolescent girls . DESIGN Early adolescent Caucasian girls ( aged 12 years , Tanner Stage 2 ) were enrolled in a r and omized trial of daily calcium supplement ( TX , 800 mg calcium carbonate and 400 IU vitamin D ) or placebo ( C ) . Body weight , height , and distal tibia measurements by pQCT were obtained at enrollment , 6 and 12 months . Pubertal status and physical activity records were assessed at baseline and 12 months . Three-day food intake records were completed every three months . RESULTS Seventy-one girls completed the 12-month trial ( TX=35 , C=36 ) . No differences were found for age , weight , height , body mass index , pubertal maturation , or reported physical activity at enrollment or during the study . Average intakes during the study were 1524 mg calcium and 496 IU vitamin D ( TX ) versus 865 mg calcium and 160 IU vitamin D ( C ) per day . Baseline total bone values were similar , however , trabecular values were greater in TX girls despite r and omization . Percent changes were calculated to adjust for baseline differences . Because of the small cortical thickness at the 10 % site ( mean values < 1.6 mm ) , cortical mass and density were not analyzed . The percent changes for trabecular bone mineral content ( BMC , mg ) and vBMD were significantly greater in TX girls ( + 4.1 % BMC and + 1.0 % vBMD TX versus -1.6 % BMC and -2.0 % vBMD C , p<0.006 ; ANCOVA ) after 12 months of supplement . Trabecular bone area ( BA , cm(2 ) ) and total bone change , however , did not differ between groups . CONCLUSIONS Daily calcium and vitamin D supplementation promotes greater trabecular BMC and vBMD acquisition in preadolescent girls . The single site selected for pQCT evaluation in this study did not allow evaluation of the cortical bone compartment . Future studies that utilize the pQCT technique need to incorporate multiple measurement sites to better assess total , cortical , and trabecular bone
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 .