Differences in body composition between Singapore Chinese, Beijing Chinese and Dutch children

Abstract

Objectives: To compare the relationship between body mass index (BMI) and body fat percentage (BF%) in children of different ethnic background. Design: Cross-sectional observational study. Setting: The study was performed in three different locations, Singapore, Beijing and Wageningen (The Netherlands). Subjects: In each centre 25 boys and 25 girls, aged 7–12 y, were selected. They were matched on age, sex and body height. Methods: Body weight and body height was measured following standardized procedures. The body mass index (BMI) was calculated as weight/height squared (kg/m²). Body fat was measured by densitometry in Beijing and Wageningen and by dual energy X-ray absorptiometry (DXA) in Singapore. The DXA measurements in Singapore were validated against densitometry. Results: There were no significant differences in BF% or BMI within each gender group across the three study sites. However, after controlling for (non-significant) differences in age and BF%, the Singapore children had a lower (mean±s.e.) BMI (15.6±0.3) than the Beijing 17.6±0.3) and Wageningen (16.9±0.3) children. For the same BMI, age and sex the Singapore children had a significant higher BF% (24.6±0.7) than the Beijing (19.2±0.8) and Wageningen (20.3±0.7) children. Conclusions: The study strongly suggests that the relationship between BF% and BMI (or weight and height) is different among children of different ethnic background. Consequently growth charts and BMI cut-off points for underweight, overweight and obesity in children may have to be ethnic-specific.