Eating-out behaviors, associated factors and associations with obesity in Chinese school children: findings from the childhood obesity study in China mega-cities

PURPOSE Eating-out and prevalence of obesity/overweight have been rising rapidly in China in the past two decades due to social economic developments. This study examined Chinese school children's eating-out behaviors and associated factors, including their association with obesity during a 3-year follow. METHODS Data were collected from 3313 primary and middle school children aged 7-16 years in five mega-cites across China in 2015, 2016 and 2017, in an open cohort study. Eating-out behaviors were assessed using questionnaire survey. The Chinese age-sex-specific body mass index (BMI) cutoffs were used defining child overweight/obesity (combined) and obesity; central obesity was defined as WHtR ≥ 0.48. Mixed effect models examined associations between child eating-out behaviors and BMI, overweight and obesity in this longitudinal data, adjusting for other covariates. RESULTS About 80.1% of the children reported having eaten out ≥ 1 times/week over the past 3 months; 46.7% and 70.9% chose Western- and Chinese-style food when ate out, respectively. Meanwhile, 29.8% of them were overweight/obese, 12.7% were obese and 20.1% had central obesity. Child eating-out behaviors were positively associated with parents' eating-out behaviors (p < 0.05). Boys were more likely to choose Western-style food than girls (OR 1.27; 95% CI 1.09-1.48) when eating out. Compared to non-overweight/obese children, those being overweight/obese at baseline were less likely to eat out dining on Western-style food during the follow-up. CONCLUSION Eating-out is common among school children in major cities in China, but with considerable differences across groups. Children's weight status was associated with eating-out behaviors.