Factors Related to Bone Mineral Content Among Adolescents in Seoul

The purpose of this study was to investigate factors related to bone mineral contents (BMC) at os calcis of adolescents. The subjects were 604 students (327 boys and 277 girls) between 7th and 9th grade in Seoul, Korea. The mean age was 14.2±0.9 years. General characteristics were collected by a questionnaire, bone mineral contents (BMC) were measured in os calcis by Duel Energy X-ray Absorptiometry (PIXI, General Electronics, USA) and height and weight were measured by bioelectrical impedance analysis method (Inbody 4.0, Biospace Co. Ltd, Seoul, Korea). Mean BMC of os calsis were 2.241 g. Height (p less than .0001), weight (p less than .0001), BMC (p less than .0001) of boys were higher than those of girls. Percent body fat of girls, however, was higher than that of boys (p less than .0001). Anthropometric measurement, pocket money, sibling, experience of fracture, pubertal stage, intake of supplements, physical or outdoors activity, and eating habit had significant influence on BMC of boys. Anthropometric measurement, physical or outdoors activity, and eating habit had significant influence on BMC of girls. Multivariate regression with adjustment for sex and age showed that BMC was associated positively with height, BMI, frequency of regular activity, and intake of spinach or radish leaves (all p less than 0.05), and negatively with percent body fat (p less than .0001) and Korean traditional diet pattern (p = 0.01). On the basis of these results, it is recommended to develop nutrition education and physical activity program for adolescents to improve BMC and prevent osteoporosis.