Contributing factors of sex difference in childhood obesity rates in China
Wang, Hsing-chun Vivian
MetadataShow full item record
Background: Childhood obesity has become a serious epidemic in China and worldwide. In China, boys are two times more likely to be overweight or obese (ow/ob) than girls, which is different from many other countries. This study examined individual and familial factors that might help to explain why there is the sex difference in childhood obesity rates in China. Methods: Data on children aged 2-18 years (n = 2,182) and at least one parent (n = 3,775) from the 2011 China Health and Nutrition Survey (CHNS) were included. We examined sex differences in children's weight status, related anthropometric measurements, behaviors and beliefs on both individual and parental levels and investigated whether these child and family factors influenced childhood obesity differently by child sex. A set of tests and logistic regression analysis were conducted to assess the sex differences. Results: Overall, ow/ob prevalence among the children was 17.0% (18.1% in boy vs. 15.8% in girls); and more boys than girls had central obesity (16.6% vs. 10.9%, p = 0.002). Boys aged 12-18 were about twice as likely to be ow/ob as girls (15.5% vs. 8.4%, p<0.05), but for those aged 2 -5, it was 21.0% in girls vs. 14.6% in boy (p < 0.05). Boys aged 12-18 were more likely to have higher energy intake exceeding recommendation (39.5% vs. 30.0%), higher sugar-sweetened beverage intake (27.1% vs. 21.5% all ages), underweight self-misperception (23.3% vs. 12.8%), and satisfaction with level of physical activity (68.0% vs. 55.2%) than girls. Girls were more likely to associate with overweight self-misperception (24.2% vs. 12.6% in boys), perception of insufficient level of physical activity (42.3% vs. 30.4%), weight loss management through diet (14.9% vs. 4.1%), and preference for thinner body shape (53.0% vs. 40.4%) than boys. Mothers with children aged 12-18 were more likely to perceive girls (9.6% vs. 1.7% for boys) as overweight and boys as underweight (22.5% vs. girls 7.8%). Conclusions: Sex differences in childhood obesity rates exist in China, and in weight-related factors on individual and parental levels, some of which may help explain the sex difference in obesity rates. Future research is needed to understand the underlying causes of sex-differences in childhood using longitudinal data and to develop effective sex-tailored interventions.