CALCIUM-ENRICHED FOODS AND BONE MASS GROWTH IN PREPUBERTAL GIRLS - A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED TRIAL

High calcium intake during childhood has been suggested to increase bo ne mass accrual, potentially resulting in a greater peak bone mass. Wh ether the effects of calcium supplementation on bone mass accrual vary from one skeletal region to another, and to what extent the level of spontaneous calcium intake may affect the magnitude of the response ha s, however, not yet been clearly established. In a double-blind, place bo-controlled study, 149 healthy prepubertal girls aged 7.9+/-0.1 yr ( mean+/-SEM) were either allocated two food products containing 850 mg of calcium (Ca-suppl.) or not (placebo) on a daily basis for 1 yr. Are al bone mineral density (BMD), bone mineral content (BMC), and bone si ze were determined at six sites by dual-energy x-ray absorptiometry. T he difference in BMD gain between calcium-supplemented (Ca-suppl.) and placebo was greater at radial (metaphysis and diaphysis) and femoral (neck, trochanter, and diaphyses) sites (7-12 mg/cm(2) per yr) than in the lumbar spine (2 mg/cm(2) per yr). The difference in BMD gains bet ween Ca-suppl. and placebo was greatest in girls with a spontaneous ca lcium intake below the median of 880 mg/d. The increase in mean BMD of the 6 sites in the low-calcium consumers was accompanied by increased gains in mean BMC, bone size, and statural height. These results sugg est a possible positive effect of calcium supplementation on skeletalI growth at that age. In conclusion, calcium-enriched foods significant ly increased bone mass accrual in prepubertal girls, with a preferenti al effect in the appendicular skeleton, and greater benefit at lower s pontaneous calcium intake.