Lifestyle factors associated with childhood obesity: a cross-sectional study in Shanghai, China

BACKGROUND: Limited research has been conducted to investigate factors associated with overweight and obesity of children in China, where obesity has been increasing. This study investigated associations of lifestyle factors with overweight or obesity among Chinese primary school-aged children. METHODS: A cross-sectional survey was conducted with 2400 children aged 6–12 from 11 primary schools. Children completed a self-administered questionnaire assisted by their parents at home. The survey included questions on self-reported height and weight, screen time, physical activity, modes of travel to/from school, and dietary habits. Multilevel models were conducted to examine factors associated with overweight or obesity. RESULTS: 15.6% of children were overweight and 11.2% were obese; nearly 80% of children spent ≤2 hrs./day either on physical activities or screen time. Compared with those spent >3 hrs./day on screen time, children who spent ≤2 hrs./day or between 2-3 hrs./day were significantly less likely to be obese after adjusting for other variables (AOR = 0.34, 95% CI: 0.20-0.60, P < 0.01; or AOR = 0.41, 95% CI: 0.20-0.84, P = 0.02 respectively). Children spent ≤2 hrs./day on screen time were less likely to become overweight or obesity, compared with >3 hrs./day (AOR = 0.62, 95% CI: 0.38-0.99, P < 0.05). CONCLUSIONS: Screen time is independently associated with childhood obesity, and needs be focused for obesity prevention in school-aged children in China.