The role of local food availability in explaining obesity risk among young school-aged children

In recent years, research and public policy attention has increasingly focused on understanding whether modifiable aspects of the local food environment the types and composition of food outlets families have proximate access to are drivers of and potential solutions to the problem of childhood obesity in the United States. Given that much of the earlier published research has documented greater concentrations of fast-food outlets alongside limited access to large grocery stores in neighborhoods with higher shares of racial/ethnic minority groups and residents living in poverty, differences in retail food contexts may indeed exacerbate notable child obesity disparities along socioeconomic and racial/ethnic lines. This paper examines whether the lack of access to more healthy food retailers and/or die greater availability of "unhealthy" food purveyors in residential neighborhoods explains children's risk of excessive weight gain, and whether differential food availability explains obesity disparities. I do so by analyzing a national survey of U.S. children followed over elementary school (Early Childhood Longitudinal Study - Kindergarten Cohort) who are linked to detailed, longitudinal food availability measures from a comprehensive business establishment database (the National Establishment Time Series). I find that children who live in residentially poor and minority neighborhoods are indeed more likely to have greater access to fast-food outlets and convenience stores. However, these neighborhoods also have greater access to other food establishments that have not been linked to increased obesity risk, including large-scale grocery stores. When examined in a multi-level modeling framework, differential exposure to food outlets does not independently explain weight gain over time in this sample of elementary school-aged children. Variation in residential food outlet availability also does not explain socioeconomic and racial/ethnic differences. It may thus be important to reconsider whether food access is, in all settings, a salient factor in understanding obesity risk among young children. (C) 2012 Elsevier Ltd. All rights reserved.