A cross-sectional study of the impact of school neighbourhood on children obesity and body composition.

Schools' neighbourhoods provide an important environmental context that may influence the risk of obesity among children. The aim of this study was to assess the effect of neighbourhood surrounding schools on obesity and body composition in schoolchildren. Data on 845 children aged 7 to 12 years old from 20 primary schools were considered. Anthropometric measurements and bioelectrical impedance analysis were performed to assess body mass index (BMI) and characterize body composition. Land use characteristics were quantified within a 500-m buffer zone around schools. Mixed-effect models measured the effects of school neighbourhood on obesity and body composition. The results showed a tendency between green urban areas around schools and lower values of BMI and better body composition parameters compared with built areas, being BMI z-scores CDC, and body fat percentage significantly higher in-built than in green urban areas (ß = 0.48, 95% CI 0.05; 0.90, and ß = 2.56, 95% CI 0.39; 4.73, respectively).Conclusion: Our findings suggest that the school neighbourhood has an effect on BMI and body fat percentage in schoolchildren. These results may contribute to the creation of healthier cities and help reduce health expenses by focusing on prevention programmes towards the expansion of green spaces. What is Known: • Living in greener areas has been associated with healthy weight outcomes and to the lower impact of obesogenic urban environments. • The school environment may be especially important for youth health outcomes. What is New: • Neighbourhoods around schools may affect child health, specifically the development of obesity. • The presence of urban green areas around school may promote a framework of lifestyle or behaviours conducive to achieving a healthy weight.