Introduction and hypothesis: Calcium supplementation enhances bone mass accrual during administration, with a sustained benefit observed using milk-based calcium but not calcium salts. We tested the hypothesis that calcium from milk minerals but not calcium carbonate will be sustained after supplementation was discontinued.
Methods: Ninety-nine pre-pubertal boys and girls aged 5-11 years were followed for 12 months after being randomized to receive 800 mg/day of calcium from milk minerals (MM) or calcium carbonate (CC), or a placebo (Pla) in a 10-month double blind study. Total body and regional BMC, and femoral shaft bone dimensions were measured using dual energy x-ray absorptiometry. Group differences were determined using ANCOVA.
Results: In the intention to treat analysis of the entire sample, no group differences were observed in increments in BMC or bone dimensions during or after supplementation. In those children who remained pre-pubertal, greater gains in pelvis BMC in the milk mineral group than controls were sustained (37.9 versus 29.3% respectively, p<0.02).
Conclusion: In healthy children consuming about 800 mg calcium daily, calcium supplementation with milk minerals or calcium carbonate does not appear to be produce biologically meaningful benefits to skeletal health. A benefit of calcium supplementation in pre-pubertal was evident, but inconclusive, with the biological significance of the effect of calcium supplementation at the pelvis, and the longevity of this effect to be determined.