Compared with dietary behavior and physical activity risk, sedentary behavior risk is an important factor in overweight and obesity: evidence from a study of children and adolescents aged 13-18 years in Xinjiang, China.

Background: Malnutrition or insufficient physical activity (PA) is a risk factor for obesity and chronic disease in children and adolescents. Affected by different economic circumstance, ethnic, dietary behavior, physical activity and other factors, children and adolescents in Xinjiang, China are facing a severe situation of overweight and obesity prevention and control. It is necessary to analyze the dietary behavior and physical activity of children and adolescents with different nutritional status and the relationship between them.

Methods: Using a stratified cluster sampling method in Xinjiang, China, 4833 middle school students aged 13-18 were selected., and tests for height and weight were conducted. Self-assessment questionnaires were completed for Dietary Behaviors, Physical Activity, and Sedentary Behaviors as well. Chi-square test, Logistic regression analysis and other methods were used to analyze the relationship between Dietary Behaviors, Physical Activity, Sedentary Behaviors and other health behavior risk factors and Weight and BMI.

Results: Children and adolescents aged 13-18 in Xinjiang, China, girls had a lower BMI compared with boys(19.49 VS. 20.41). The proportions of Underweight, Overweight and Obese among girls were lower (Underweight: 11.8 VS. 14.5; Overweight: 7.6 VS. 12.7; Obese 2.3 VS. 7.0).Boys with higher risk of sedentary had a 1.46-fold higher risk of developing Overweight/Obese than those with lower risk of sedentary (95%CI: 1.07-2.01).Girls with higher risky diet had a 1.56-fold higher risk of developing Underweight than those with lower risky diet (95%CI: 1.11-2.19). For all participants, the risk of Overweight/Obese in children and adolescents with higher risk of sedentary was 1.45 times more than that of children and adolescents with lower Risk sedentary (95%CI: 1.12 ~ 1.88). Overall, Weight had a significant correlation with PA risk (r = 0.076, P < 0.01) and sedentary behavior risk (r = 0.035, P < 0.05). BMI had a key correlation with PA risk (r = 0.064, P < 0.01) and sedentary behavior risk (r = 0.037, P < 0.05).

Conclusions: The detection rate of Underweight among children and adolescents aged 13-18 in Xinjiang, China is higher, while the detection rate of Overweight and Obese is lower than that of the whole country. Static behavior was an important factor affecting the occurrence of Overweight and Obese in children and adolescents, and the performance of boys was more obvious than that of girls.The results further improve the data on the weight status of Chinese children and adolescents and their influencing factors, and call on Chinese society and schools to continue their efforts to prevent and reduce malnutrition and obesity among children and adolescents in Xinjiang.