Dietary Knowledge, Attitudes, and Behaviors Related to Obesity and Highly Underweight Among Urban Chinese High School Students: A Cross-Sectional Study

Objectives This study aimed to identify dietary knowledge, attitudes, and behaviors related to obesity and highly underweight among urban Chinese high school students.Methods Using the data of 403 high school students from a cross-sectional survey in 2022, multinomial logistic regression analysis was conducted with the body mass index as the objective variable (reference: normal weight), dietary knowledge, attitudes, and behaviors as the explanatory variables, adjusted for sex.Results Both obesity and highly underweight were most strongly related to incorrect dietary knowledge of desirable types of diets. Additionally, obesity was related to inappropriate dietary attitudes regarding the importance of diet, eating at irregular meal-times, and eating without chewing well, while highly underweight was related to picky eating and not having three meals per day, but not related to attitudes.Conclusion The incorrect knowledge of desirable type of diet was related to both obesity and highly underweight, while other risk factors of knowledge, attitudes, and behaviors related to obesity or highly underweight differed respectively. These findings should be useful in examining effective nutrition education for urban Chinese high school students.