Green neighborhoods, food retail and childhood overweight: differences by population density.

PURPOSE: This study examines relationships between overweight in children and two environmentalfactors--amount of vegetation surrounding a child's place of residence and proximity of the child's residence to various types of food retail locations. We hypothesize that living in greener neighborhoods, farther from fast food restaurants, and closer to supermarkets would be associated with lower risk of overweight.
DESIGN: Cross-sectional study.
SETTING: Network of primary care pediatric clinics in Marion County, Indiana.
SUBJECTS: We acquired data for 7334 subjects, ages 3 to 18 years, presenting for routine well-child care. MEASURES: Neighborhood vegetation and proximity to food retail were calculated using geographic information systems for each subject using circular and network buffers. Child weight status was defined using body mass index percentiles. Analysis. We used cumulative logit models to examine associations between an index of overweight, neighborhood vegetation, and food retail environment.
RESULTS: After controlling for individual socio-demographics and neighborhood socioeconomic status, measures of vegetation and food retail significantly predicted overweight in children. Increased neighborhood vegetation was associated with decreased risk for overweight, but only for subjects residing in higher population density regions. Increased distance between a subject's residence and the nearest large brand name supermarkets was associated with increased risk of overweight, but only for subjects residing in lower population density regions.
CONCLUSIONS: This research suggests that aspects of the built environment are determinants of child weight status, ostensibly by influencing physical activity and dietary behaviors.