Prolonged exposure to polluted air and risk of overweight and central obesity in Chinese children and adolescents

The rapid economic development in China has led to significant challenges in air pollution. This study examines the relationship between prolonged exposure to air pollution and the prevalence of overweight and central obesity among Chinese children and adolescents. A total of 161,093 children and adolescents (aged 9–18) from 32 provinces in China were analyzed. Ambient air pollution (PM2.5, PM10, SO2, NO2, O3, CO) was assessed using satellite models. Overweight and central obesity were measured via BMI, waist circumference, and Waist-to-Height Ratio (WHtR). Mixed-effects regression models were adjusted for demographic and behavioural factors, with sensitivity analyses conducted for exposure windows. PM2.5 was significantly associated with an increased risk of being overweight (OR = 1.212, 95% CI: 1.169–1.257, p < 0.001). SO2 (OR = 1.103, 95% CI: 1.069–1.139, p < 0.001), NO2 (OR = 1.069, 95% CI: 1.051–1.087, p < 0.001), and reciprocal CO (OR = 1.052, 95% CI: 1.043–1.061, p < 0.001) also showed positive associations. In contrast, PM10 (OR = 0.954, 95% CI: 0.938–0.969, p < 0.001), AQI (OR = 0.959, 95% CI: 0.935–0.983, p < 0.001), and O3 (OR = 0.949, 95% CI: 0.935–0.962, p < 0.001) were negatively associated with overweight. For central obesity, AQI (OR = 1.118, 95% CI: 1.095–1.141, p < 0.001) and NO2 (OR = 1.065, 95% CI: 1.051–1.079, p < 0.001) showed positive associations, while PM10 (OR = 0.901, 95% CI: 0.889–0.913, p < 0.001) and O3 (OR = 0.973, 95% CI: 0.962–0.985, p < 0.001) were inversely associated. SO2 and CO−1 were not statistically significant for central obesity after full adjustment. Boys, high school students, and children from low-income or southern regions exhibited stronger associations. Similar trends were observed for central obesity. Prolonged air pollution exposure significantly increases the risks of overweight and central obesity in Chinese children and adolescents.