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 .
[Effects of calcium supplementation using AAACa or milk on nocturnal bone resorption in young women].
In order to study the effect of calcium supplementation on bone resorption , a r and omized controlled crossover study was carried out on eight healthy 18 - 19 year old female volunteers using either AAACa heated oyster shell with vacuum-heated seaweed or milk .  Regimen A consisted of an oral dose of 200 mg calcium in the form of AAACa . B 200 ml milk after breakfast and supper and at bedtime , and C control with no calcium supplement .  Early morning fasting blood and urine sampling was carried out after 7 days of calcium supplementation .  Serum calcium was higher in groups A and B than in C , and serum intact parathyroid hormone ( PTH ) was significantly lower in group A than in groups B and C , according to a paired t-test . Urinary excretion of crosslinked collagen degradation product , pyridinoline and deoxypyridinoline showed a similar decrease in groups A and B but not in C. The more effective suppression of PTH by AAACa than by milk may be due to its higher bioavailability and the absence of phosphate stimulating PTH secretion
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 .