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 intake and bone mineral acquisition in adolescent girls: randomised, controlled intervention trial
Abstract Objectives : To investigate the effect of milk supplementation on total body bone mineral acquisition in adolescent girls . Design : 18 month , open r and omised intervention trial . Subjects : 82 white girls aged 12.2 ( SD 0.3 ) years , recruited from four secondary schools in Sheffield . Intervention : 568 ml ( one pint ) of whole or reduced fat milk per day for 18 months . Main outcome measures : Total body bone mineral content and bone mineral density measured by dual energy x ray absorptiometry . Outcome measures to evaluate mechanism included biochemical markers of bone turnover ( osteocalcin , bone alkaline phosphatase , deoxypyridinoline , N-telopeptide of type I collagen ) , and hormones important to skeletal growth ( parathyroid hormone , oestradiol , insulin-like growth factor I ) . Results : 80 subjects completed the trial .  Daily milk intake at baseline averaged 150 ml in both groups . The intervention group consumed , on average , an additional 300 ml a day throughout the trial . Compared with the control group , the intervention group had greater increases of bone mineral density ( 9.6 % v 8.5 % , P=0.017 ; repeated measures analysis of variance ) and bone mineral content ( 27.0 % v 24.1 % , P=0.009 ) . No significant differences in increments in height , weight , lean body mass , and fat mass were observed between the groups . Bone turnover was not affected by milk supplementation . Serum concentrations of insulin-like growth factor I increased in the milk group compared with the control group ( 35 % v 25 % , P=0.02 ) . Conclusion : Increased milk consumption significantly enhances bone mineral acquisition in adolescent girls and could favourably modify attainment of peak bone mass . Key messages Osteoporosis is a major public health problem ; 40 % of women will sustain an osteoporotic fracture Maximising peak bone mass at skeletal maturity may be one of the most important protective measures against fracture in later life Adolescence is a critical time for bone mineral acquisition An increase in milk consumption among adolescent girls result ed in significant gains in bone mineral over an 18 month period This simple intervention indicates that increased milk consumption may be associated with higher peak 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 .