Background: There are known to be ethnic differences in body composition in adults which are related to ethnic differences in adult disease.
Objectives: To evaluate gender and ethnic differences in percentage body fat in British schoolchildren and to compare these with classification of obesity using body mass index criteria.
Design: A cross-sectional study of 1251 healthy children and adolescents aged 5 to 18 years from three ethnic groups, White, South Asian and African-Caribbean. Percentage body fat was determined by dual x-ray absorptiometry and the subjects classified using body mass index criteria for overweight and obesity.
Results: Significant gender differences in percentage body fat were seen with girls having higher values from the age of 5 years. Girls had 3.8% higher percentage body fat at 5 years increasing to 12.9% at age 18 years. Significant ethnic differences were found with South Asian girls and boys having the highest percentage body fat from age 5 and 7 years respectively. These differences increased with age being most significant in the teenage years. Although South Asian girls and boys were overrepresented in a group containing children with more than 25% body fat (p < 0.0001 Chi-square) African-Caribbean subjects were more likely to be classified as obese using body mass index criteria.
Conclusions: There are clear gender and ethnic differences in percentage body fat in British schoolchildren which may relate to known differences in the risk of Type 2 diabetes in adolescence and adulthood. Body mass index criteria for defining overweight and obesity do not accurately identify ethnic differences in body fat.
- British schoolchildren
- body fat
- ethnic differences