Association between the food retail environment surrounding schools and overweight in Canadian youth.

INTRODUCTION: There is growing interest in how the physical environment influences obesity. Few studies have considered how the food retail environment surrounding schools influences overweight in students. OBJECTIVE: To determine whether there is a relationship between food retailers surrounding schools and overweight among Canadian youth. DESIGN: Cross-sectional study. SETTING/METHODS/SUBJECTS: The number of food retailers was obtained within a 1 km and 5 km radius around 178 schools in Canada. Retailers included full-service restaurants, fast-food restaurants, sub/sandwich retailers, doughnut/coffee shops, convenience stores and grocery stores. An index of total food retailer exposure was also created. Multilevel analyses were used to control for individual- and area-level covariates. RESULTS: None of the individual food retailers was associated with an increased likelihood of overweight. The total food retailer index was most strongly related to overweight, but in the opposite direction to that hypothesized. At 1 km, students attending schools with at least one food retailer had a lower relative odds of overweight (OR = 0.70, 95% CI 0.61, 0.81). At 5 km, students attending schools with the highest exposure to the total food retailer index had a lower relative odds of overweight (OR = 0.56, 95% CI 0.47, 0.68) compared with students attending schools with no exposure. CONCLUSIONS: Exposure to various types of food retailers in school neighbourhoods was not associated with an increased likelihood of overweight in Canadian school-aged youth. The opportunity to make healthy choices from a variety of options and the unique Canadian context may explain the findings.

Density and type of food retailers surrounding Canadian schools: variations across socioeconomic status.

Lower socioeconomic status (SES) neighbourhoods may have differential access to food retailers, potentially explaining the varying area-level obesity rates. The food retail environment around 188 schools across Canada was examined, including full-service restaurants, fast food restaurants, sub/sandwich retailers, donut/coffee shops, convenience stores, and grocery stores. School addresses were linked to census data to obtain area-level SES measures. Access to food retailers was generally not associated with the neighbourhood SES in the immediate proximity. Within the broader neighbourhood, lower SES neighbourhoods had access to fewer food retailers of all types. This effect was diminished after taking population density into account.