Comparison of Body Composition between Tibetan and Han Adolescents

  Objective  To compare body composition between Tibetan adolescents and Han adolescents with a large-scale population survey.

  Methods  Totally, 707 Tibetan adolescent living in a 3000-meter-altitude area and 733 Han adolescents living in a low-altitude area, all aged from 10-18 years, were surveyed in Sichuan province with two-stage stratified cluster sampling. Their body composition were arrayed with Biodynamics BI-310 body composition analyzer.

  Results  The average height of Tibetan adolescents was lower than that of Hans (male:150.06 cm vs. 154.03 cm, P < 0.001; female:147.28 cm vs. 151.06 cm, P < 0.001). There were not significant differences in body weight and body mass index in boys; the body weight in girls also showed nosignificant difference, while Tibetan girls' body mass index was bigger than that of Hans (19.33 kg/m² vs. 18.46 kg/m², P < 0.001). The lean body mass of Tibetan adolescents was significantly smaller than that of Hans (male:35.20 kg vs. 39.05 kg, P < 0.001; female:32.25 kg vs. 35.60 kg, P < 0.001), but fat body weight of Tibetan adolescents was significantly larger than that of Hans(male:5.90 kg vs. 3.40 kg, P < 0.001; female:9.65 kg vs. 7.25 kg, P < 0.001). Fat mass index of Tibetan adolescents was higher than that of Hans, but fat-free mass index in Tibetan adolescents was significantly lower. The body fat percentages of Tibetan boys and girls were higher than Han adolescents by 6.62%(14.89% vs. 8.27%, P < 0.001) and 6.42%(23.26% vs. 16.84%, P < 0.001), respectively. In the age range of 10-17 years, body fat percentage of Tibetan adolescents was larger by 4% to 7% than that of Han adolescents in all age groups in both sexes.

  Conclusions  The body compositions of Tibetan adolescents living in high-altitude areas may be significantly different from that of Hans living in low-altitude areas because of genetic, environmental, and other factors. Tibetan adolescents have higher body fat percentage compared with Han adolescents in same age and sex.