School and residential neighborhood food environment and diet among California youth

Background: Various hypotheses link neighborhood food environments and diet. Greater exposure to fast-food restaurants and convenience stores is thought to encourage overconsumption; supermarkets and large grocery stores are claimed to encourage healthier diets. For youth, empirical evidence for any particular hypothesis remains limited.

Purpose: This study examines the relationship between school and residential neighborhood food environment and diet among youth in California.

Methods: Data from 8226 children (aged 5-11 years) and 5236 adolescents (aged 12-17 years) from the 2005 and 2007 California Health Interview Survey were analyzed in 2011. The dependent variables are daily servings of fruits, vegetables, juice, milk, soda, high-sugar foods, and fast food, which were regressed on measures of food environments. Food environments were measured by counts and density of businesses, distinguishing fast-food restaurants, convenience stores, small food stores, grocery stores, and large supermarkets within a specific distance (varying from 0.1 to 1.5 miles) from a respondent's home or school.

Results: No robust relationship between food environment and consumption is found. A few significant results are sensitive to small modeling changes and more likely to reflect chance than true relationships.

Conclusions: This correlational study has measurement and design limitations. Longitudinal studies that can assess links between environmental, dependent, and intervening food purchase and consumption variables are needed. Reporting a full range of studies, methods, and results is important as a premature focus on correlations may lead policy astray.