Calcium supplementation for 2 years improves bone mineral accretion and lean body mass in Chinese adolescents.
OBJECTIVE
to study the effects of different doses of calcium intake on bone health and body composition in Chinese adolescents.


METHODS
a double-blind randomized controlled trial of calcium carbonate supplementation in 257 healthy adolescents aged 12-15 years old for 24 months. Subjects were randomly assigned to four groups receiving chewable calcium carbonate tablets providing elemental calcium at 63 mg/d, 354 mg/d, 660 mg/d, 966 mg/d, respectively. At the end of intervention, we reclassified 197 adolescents into 3 groups who had received actual doses of elemental calcium of 85 mg/d (Low dose), 230 mg/d (Medium dose) and 500 mg/d (High dose). We measured bone mineral content (BMC), bone mineral density (BMD) and body composition by dual-energy X-ray absorptiometry.


RESULTS
BMC and BMD of total body and lumbar spine were increased significantly in both males and females after intervention at all doses (p<0.05). In males, after supplementation, total body BMC in the medium and high dose groups (2464 g and 2437 g, respectively) was significantly higher than that in the low dose group (2321 g) after adjusting for age, pubertal development, BMI, physical activity and energy intake; in addition, lean body mass in the medium and high dose groups (49.1 kg and 48.8 kg, respectively) was significantly higher than that in the low dose group (46.7 kg) (p<0.05). There was no significant effect of calcium supplementation on bone mass or body composition in females.


CONCLUSIONS
calcium supplementation more than 230 mg/d for two years can improve bone mineral accretion and lean body mass in Chinese male adolescents.
Yin
Jing
J
National Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, 7 Pan Jia Yuan Nan Li, Beijing, China. mags@chinacdc.net.cn
Zhang
Qian
Q
Liu
Ailing
A
Du
Weijing
W
Wang
Xiaoyan
X
Hu
Xiaoqi
X
Ma
Guansheng
G
D015502:Absorptiometry, Photon; D000293:Adolescent; D044466:Asian People; D001823:Body Composition; D015992:Body Mass Index; D015519:Bone Density; D002119:Calcium Carbonate / Q000008:administration & dosage; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002648:Child; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D012727:Sex Characteristics; D011795:Surveys and Questionnaires; D051598:Whole Body Imaging
D002136:Calcium, Dietary; D002119:Calcium Carbonate