Retail food environment around schools and overweight: a systematic review

Context: The presence of retail food establishments around schools can be a potentiating or protective factor for overweight in students, depending on access to these places as well as types of foods available therein. The hypothesis for this study was that a greater density and proximity of retail food establishments around schools influence the weight of students. Objective: To systematically review the available observational literature on the association between retail food establishments around schools and the occurrence of overweight and obesity in schoolchildren and adolescents. Data Sources: Observational studies were searched in the MEDLINE, EMBASE, and SCOPUS databases published until May 2019. Data Extraction: Two independent reviewers extracted relevant data. Data Analysis: Data on the 31 included studies were summarized with narrative synthesis according to meta-analyses of observational studies in epidemiology, exploring the type of food establishments around schools and analyzing qualitatively the impact of proximity or density on overweight and obesity rates. Conclusion: Of the 31 articles, a direct association between proximity or density of establishments (mainly fast food restaurants, convenience stores, grocery stores) around schools and overweight and obesity in children and adolescents were found in 14 studies. However, authors of 13 papers found no association and inverse association was presented in 4 papers. The studies presented different methods of classification, location, and analysis of retail food establishments, making it difficult to conclude the real influence that the presence of these establishments near schools have on the nutritional status of children and adolescents. Therefore, future studies should consider the use of longitudinal designs and standardized analysis of the food environment around schools to better understand this food environment and its influence on health-related behaviors.