Long-term exposure to outdoor air pollution correlated with overweight/obesity in children and adolescents: A cross-sectional real-world study

Air pollution has emerged as an essential risk factor for overweight and obesity. However, the combined effects of multiple air pollutants on overweight/obesity development in children and adolescents are not fully understood. In this study, a total of 189,448 children and adolescents in China were included. Logistics, weighted quantile sum, quantile g-computation, and bayesian kernel machine regression models were used to systematically assess the association between long-term outdoor air pollution exposure and overweight/obesity, and identified the major contributors. Our results revealed a significantly positive association of PM_2.5, PM₁₀, CO, and NO₂ concentrations with overweight/obesity risk. Multi-pollutant models consistently demonstrated a positive association between the air pollutant mixture and the risk of overweight/obesity (OR: 1.825; 95 % CI: 1.036, 2.614). PM_2.5 and PM₁₀ were identified as the most significant contributors. Furthermore, we found significantly positive overall effects and interactions of these pollutants on an additive risk of overweight/obesity. The effects of air pollutants on overweight/obesity were pronounced in boys, rural residents, smokers, and primary school students. Our findings demonstrated that long-term exposure to air pollutants, particularly PM_2.5 and PM₁₀ was positively linked with an increased risk of overweight/obesity in children and adolescents. The cross-sectional design and potential confounders limited the ability to establish causality. Prospective cohort studies and specific mechanism investigations are needed to provide more precise and robust evaluations in the future. Coordinated policies to reduce air pollutants and mitigate their combined effects are essential for addressing this public health issue.