Percentage body fat in apparently healthy school children from northern India.

CONTEXT Increased prevalence of obesity in childhood and adolescence, defined by the use of body mass index (BMI), has drawn attention towards direct measurement of body fat. OBJECTIVE To develop age-and sex-specific reference distribution of body fat in apparently healthy North-Indian children in the age group of 7-17 years and to assess agreement between obesity (defined by BMI) and excess body fat. DESIGN Study subjects for this cross sectional study included 1640 apparently healthy school children (825 boys; 815 girls) aged 7-17 years. Total body fat was measured by dual energy X-rays absorptiometry (DXA). The excess body fat by DXA was defined by two methods, prevalence matching and with the use of 85th and 95th centile cutoffs. RESULTS The mean ± SD, 3rd, 10th, 25th, 50th, 75th, 90th and 97th centile values of percentage body fat (PBF) are presented. PBF was highly correlated with BMI in both boys and girls (all boys: r=0.76, P<0.0001; all girls r=0.81, P<0.0001). There was no significant difference noted in PBF between boys and girls at the age of 7-8 years. From 9 years onwards, girls had significantly higher PBF than boys. Moderate degree of agreement was observed between BMI and PBF by DXA by both methods. CONCLUSIONS Smoothened reference distribution of PBF for North-Indian children and adolescents in Delhi are provided. Indian children accumulate more body fat during peri-pubertal years in comparison with US children.