title: Calcium supplementation and bone mineral accretion in Chinese adolescents aged 12-14 years: a 12-month, dose-response, randomised intervention trial.
abstract: A 12-month, dose-response, randomised, intervention trial was conducted to determine adequate Ca intake levels for Chinese adolescents by investigating the effect of Ca supplementation on bone mineral accretion. A total of 220 Han adolescents (111 girls and 109 boys) aged 12-14 years were recruited. All subjects were randomly divided into three groups. The bone mineral content (BMC) and bone mineral density (BMD) of the whole body, lumbar spine (L1-L4), left hip and femoral neck were measured by dual-energy X-ray absorptiometry. Girls in the high-Ca group (actual Ca intake: 1243 (sd 193) mg/d) exhibited greater increases in the femoral neck BMC compared with those in the low-Ca group (9·7 v. 6·4 %, P =0·04) over the 1-year intervention period. The increases in femoral neck BMC were greater in boys in the high-Ca and medium-Ca groups (actual Ca intake: 985 (sd 168) mg/d) than in those in the low-Ca group (15·7 v. 11·7 %, P =0·03; 15·8 v. 11·7 %, P =0·03). Ca supplementation had significant effects on the whole-body BMC and BMD in subjects with physical activity levels>34·86 metabolic equivalents and on the spine BMD and BMC and BMD of most sites in subjects with Tanner stage < 3. Increasing Ca intake levels with Ca supplementation enhanced femoral neck mineral acquisition in Chinese adolescents. Furthermore, high physical activity levels and low Tanner stage appeared to significantly contribute to the effect of Ca supplementation on bone mass. Whether this is a lasting beneficial effect leading to the optimisation of peak bone mass needs to be determined in other long-term prospective studies.
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University,Guangzhou510080,People's Republic of China.
authors.forename: Xiao-ming
authors.initials: XM
authors.lastname: Ma
authors.affiliation: Key Lab of Trace Element Nutrition of Ministry of Health, National Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention,Beijing100021,People's Republic of China.
authors.forename: Zhen-wu
authors.initials: ZW
authors.lastname: Huang
authors.affiliation: Key Lab of Trace Element Nutrition of Ministry of Health, National Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention,Beijing100021,People's Republic of China.
authors.forename: Xiao-guang
authors.initials: XG
authors.lastname: Yang
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University,Guangzhou510080,People's Republic of China.
authors.forename: Yi-xiang
authors.initials: YX
authors.lastname: Su
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000818:Animals; D015519:Bone Density / Q000187:drug effects*; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002648:Child; D002681:China; D004032:Diet; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D005272:Femur Neck; D057141:Food, Preserved; D006801:Humans; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae; D008297:Male; D008892:Milk; D009043:Motor Activity; D011627:Puberty / Q000502:physiology; D012737:Sex Factors; D011795:Surveys and Questionnaires
chemical_list: D002136:Calcium, Dietary