Prevalence of overweight/obesity, and associated factors among adolescents aged 12 ∼ 15 in Shandong Province, China: A cross-sectional study

Overweight/obesity among adolescents in Shandong Province, China, has been rising, posing significant public health challenge. Comprehensive investigation is needed to develop effective interventions. Following the Strengthening the Reporting of Observational Studies in Epidemiology guidelines, a stratified random cluster sampling approach was used from September to October 2023 across 17 cities in Shandong Province. The study included 165 middle schools, surveying 99,638 students aged 12 ∼ 15. After applying exclusion criteria, 97,356 students (97.71% effective rate) completed anthropometric measurements and questionnaires. Overweight/obesity were assessed based on national and international standards. Univariable chi-square test and multivariable logistic regression were used to analyze factors influencing overweight/obesity. In 2023, the overweight/obesity rate among 12 ∼ 15-year-olds in Shandong was 19.75%. Significant factors included sex, age, residence, family income, parental weight status and activity, mother’s gestational diabetes history, birth weight, physical activity, sleep, screen time, homework, and diet. Girls, older adolescents, and those with physically active parents or who themselves engaged in over 1.5 hours of daily physical activity had lower odds of being overweight/obese. Adequate sleep and frequent consumption of vegetable and fruit were also protective. Higher odds were associated with urban residence, high family income, overweight/obese parents, maternal gestational diabetes, high birth weight, excessive screen time, extensive homework, and frequent fast food consumption. Overweight/obesity in Shandong adolescents is influenced by multiple determinants. Holistic interventions addressing genetic, behavioral, and environmental factors are essential for promoting healthier lifestyles and reducing the prevalence in this demographic.