A RANDOMIZED DOUBLE-BLIND CONTROLLED CALCIUM SUPPLEMENTATION TRIAL, AND BONE AND HEIGHT ACQUISITION IN CHILDREN

There is limited information relating Ca intake to bone and height acq uisition among Oriental children who consume little or even no milk. T he present controlled study investigated the acquisition of bone mass and height of Chinese children with an initial Ca intake of approximat ely 567 mg/d who were supplemented to about 800 mg/d. Eighty-four 7-ye ar-old Hong Kong Chinese children underwent an 18-month randomized, do uble-blind, controlled Ca-supplementation trial, The children were ran domized to receive either 300 mg elemental Ca or a placebo tablet dail y, Bone mass of the distal one-third radius was measured by single-pho ton absorptiometry, lumbar spine and femoral neck were determined usin g dual-energy X-ray absorptiometry, Measurements were repeated 6-month ly, Baseline serum 25-hydroxycholecalciferol concentration and physica l activity were also assessed, Baseline Ca intakes of the study group and controls were respectively 571 (SD 326) and 563 (SD 337) mg/d, The re were no significant differences in baseline serum 25-hydroxycholeca lciferol concentration (P = 0.71) and physical activity (P = 0.36) bet ween the study and control groups, After 18 months the study group had significantly greater increases in lumbar-spinal bone mineral content (20.9 v. 16.34%; P = 0.035), lumbar-spinal area (11.16 v. 8.71%; P = 0.049), and a moderately greater increment In areal bone mineral densi ty of the radius (7.74 v. 6.00%; P = 0.081) when compared with the con trols, The results confirm a positive effect of Ca on bone mass of the spine and radius but no effects on femoral-neck and height increase, A longer trial is warranted to confirm a positive Ca effect during chi ldhood that may modify future peak bone mass.