Energy Balance‐related School Environment/Policy Factors and Childhood Obesity in China: A National Study of 19,487 Students from 112 Middle Schools
Authors: Li Miao , Xue Hong , Min Jungwon , Wen Ming , Wang Weidong , Wang Youfa 
Published: November 2023

ObjectivesChildhood obesity in China is on the rise. School environment is very important for the development of obesity for children. This study examined regional variations in childhood obesity and school environments/policies and their associations among junior high students in China.MethodsAnalyses were based on the China Education Panel Survey: Junior High Cohorts (Wave 2013–14), which includes the first nationally representative sample of 19,487 students in 112 schools from 28 regions across China. We assessed regional variations in student BMI, overweight/obesity rates, and energy balance‐related school environment/policy factors. Multilevel models were fitted to evaluate associations between school factors and child BMI.ResultsOverweight/obesity prevalence was 21.7% in boys and 13.2% in girls (for obesity, the rate was 6.8% vs 2.4%). Urban schools in economically developed regions had the highest overweight/obesity rate (25.1%), followed by rural schools in developed regions (17.4%), urban schools in less developed regions (16.9%), and rural schools in less developed regions (11.4%). Multiple school factors displayed significant between‐region heterogeneity: Schools in developed regions were less likely to have student cafeteria (OR=.19, 95% CI=[.05, .68]), to require night study sessions (OR=.05, CI=[.02, .14]), to provide student boarding (OR=.08, CI=[.02, .24]), and to have >6 hours of coursework per weekday (OR=.06, CI=[.01, .31]) than schools in less developed regions. As for within‐region variations, school boarding facility was more prevalent among rural schools in both developed and less developed regions (71% vs. 35% in developed regions, 27% vs 0 in less developed regions). Results from gender‐specific multilevel models controlling for student traits and school location show that absence of cafeteria was associated with higher BMI for boys (β=.29, CI=[.05,.52]), while absence of boarding facility was associated with higher BMI for both boys (β=.57, CI=[.31,.83]) and girls (β=.32, CI=[.11,.54]). Longer day‐time coursework was associated with lower BMI for both boys (β=−.35, CI=[−.61,−.10]) and girls (β=−.30, CI=[−.51,−.09]). Night study session was associated with lower BMI for both boys (β=−.35, CI=[−.61,−.10]) and girls (β=−.35, CI=[−.61,−.10]). Student BMI was significantly lower in schools without gymnastic facilities that those with (for boys: β=−.51, CI=[−.77,−.24], for girls: β=−.37, CI=[−.59,−.15]).ConclusionsThis is the first study reporting energy balanced‐related school environment/policy factors in China using nationally representative data. There is significant across‐ and within‐region variation in these factors among junior high schools in China. Students’ BMI and weight status seem be affected by school factors. Further studies are warranted to examine the impact of school curriculum/course time, food policy/environment, and related school facilities on Chinese children's weight status.Support or Funding InformationFunding: NIH U54 center grant, HD070725.