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 .
Effect of parenteral calcium and phosphorus therapy on mineral retention and bone mineral content in very low birth weight infants.
HYPOTHESIS If calcium and phosphorus are administered to very low birth weight infants in amounts larger than those currently used in st and ard parenteral nutrition solutions , apparent retention of calcium and phosphorus ( intake minus urinary excretion ) will increase and bone mineralization will improve . DESIGN R and omized , controlled , double-blind trial . SETTING Neonatal intensive care unit . PATIENTS Twenty-four very low birth weight infants ( < 1.2 kg ) expected to receive parenteral nutrition exclusively for approximately 3 weeks beginning 3 days after birth . INTERVENTIONS Infants received parenteral nutrition solutions , either the st and ard mixture containing 1.25 mmol calcium and 1.5 mmol phosphorus per deciliter ( group ST AND : n = 12 , birth weight 921 + /- 171 gm , gestational age 27 + /- 2 weeks ( mean + /- SD ) ) or 1.7 mmol calcium and 2.0 mmol phosphorus per deciliter ( group HIGH : n = 12 , 857 + /- 180 gm , 27 + /- 2 weeks ) . MAIN OUTCOME MEASURES Intake , urinary excretion , and apparent retention of calcium , phosphorus , and magnesium every 3 days during parenteral nutrition therapy .  Serum indexes of mineral status twice during therapy . Bone mineral content of the distal segment of the left radius at 1 , 4 , 8 , and 26 weeks . RESULTS Apparent calcium retention ( 1.2 + /- 0.2 vs 1.6 + /- 0.2 mmol.kg-1.d-1 ) and phosphorus retention ( 1.4 + /- 0.2 vs 1.8 + /- 0.4 mmol.kg-1.d-1 ) differed significantly ( p < 0.01 ) between groups ST AND and HIGH , respectively ; neither changed with the duration of parenteral nutrition therapy . Serum calcium , magnesium , parathyroid hormone , 25-hydroxyvitamin D , and osteocalcin concentrations were similar in both groups . Serum phosphorus concentration was significantly higher in group HIGH than in group ST AND ( p = 0.025 ) . The absolute bone mineral content and the rate of increase in bone mineral content between 1 and 4 , 1 and 8 , and 1 and 26 weeks were significantly greater in group HIGH than in group ST AND . CONCLUSIONS Increased parenteral intakes of calcium and phosphorus result ed in greater retention of these minerals during parenteral nutrition therapy and in greater bone mineral content after therapy
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 .