Risks and Benefits of Green Spaces for Children: A Cross-Sectional Study of Associations with Sedentary Behavior, Obesity, Asthma, and Allergy

TLDR

Green spaces have been linked to both health benefits and risks in children, yet evidence simultaneously examining these conflicting effects across different types of greenness remains scarce. This study aimed to evaluate the health benefits and risks of various greenness types in children, focusing on sedentary behavior, obesity, current asthma, and allergic rhinoconjunctivitis. We conducted a cross‑sectional survey of 3,178 9‑12‑year‑old schoolchildren in Sabadell, Spain, in 2006, collecting questionnaire data and measuring residential surrounding greenness via satellite‑derived NDVI within 100‑to‑1,000‑m buffers and proximity to forests or parks within 300 m. Logistic regression revealed that higher surrounding greenness was associated with 11‑19% lower prevalence of overweight/obesity and excessive screen time but no effect on asthma or allergy, forest proximity reduced excessive screen time by 39% and overweight/obesity by 25% without affecting asthma, whereas park proximity increased current asthma prevalence by 60% with only weak negative effects on obesity or screen time, illustrating distinct benefit‑risk patterns for different greenness types.

Abstract

Green spaces have been associated with both health benefits and risks in children; however, available evidence simultaneously investigating these conflicting influences, especially in association with different types of greenness, is scarce.We aimed to simultaneously evaluate health benefits and risks associated with different types of greenness in children, in terms of sedentary behavior (represented by excessive screen time), obesity, current asthma, and allergic rhinoconjunctivitis.We conducted a cross-sectional study of a population-based sample of 3,178 schoolchildren (9-12 years old) in Sabadell, Spain, in 2006. Information on outcomes and covariates was obtained by questionnaire. We measured residential surrounding greenness as the average of satellite-derived Normalized Difference Vegetation Index (NDVI) in buffers of 100 m, 250 m, 500 m, and 1,000 m around each home address. Residential proximity to green spaces was defined as living within 300 m of a forest or a park, as separate variables. We used logistic regression models to estimate associations separately for each exposure-outcome pair, adjusted for relevant covariates.An interquartile range increase in residential surrounding greenness was associated with 11-19% lower relative prevalence of overweight/obesity and excessive screen time, but was not associated with current asthma and allergic rhinoconjunctivitis. Similarly, residential proximity to forests was associated with 39% and 25% lower relative prevalence of excessive screen time and overweight/obesity, respectively, but was not associated with current asthma. In contrast, living close to parks was associated with a 60% higher relative prevalence of current asthma, but had only weak negative associations with obesity/overweight or excessive screen time.We observed two separable patterns of estimated health benefits and risks associated with different types of greenness.