Familial clustering of overweight and obesity among schoolchildren in northern China.

BACKGROUND We aimed to study the prevalence of overweight and obesity and to assess its familial clustering among schoolchildren in northern China. METHODS A cross-sectional study was conducted on 95,292 schoolchildren in northern China to investigate the prevalence of overweight and obesity. A group of overweight and obese children (n = 450) was selected using a cluster sampling method. Answers from a questionnaire on their and their families' nutrition and behaviors were recorded and analyzed statistically. RESULTS The prevalence of overweight and obesity in schoolchildren was 27.4% and 13.2%, respectively. The prevalence of overweight and obesity were significantly higher in boys than in girls. The prevalence of familial clustering of overweight and obesity was 75.3% and 20.3%, respectively. The prevalence of overweight in first-generation (parents) and second-generation (grandparents) relatives was 54.6% and 53.1%, respectively. There was a linear trend toward correlation between age and the rates of overweight and obesity. The familial clustering of obesity with family income reached statistical significance. CONCLUSION The prevalence of overweight and obesity was extremely high, especially among boys and their fathers. Evidence of familial clustering of overweight and obesity among schoolchildren and their parental family members in northern China is emerging.