Explaining obesity with urban form: a cautionary tale

In recent years, there has been a dramatic increase in studies exploring associations between the built environment and obesity. Many studies have found that built environment characteristics, such as high-density land developments, mixed-land uses, and connected street networks, are associated with lower rates of obesity. However, depending on the research field and the researcher, how one specifies the experimental model and how sociodemographic characteristics of the population are defined and included in the model has led to different policy conclusions and implications. This is not a surprising observation; however, it is one that does seem to have been lost in current discussions. This article highlights several data-processing, model-specification, and model-estimation factors that should be comprehensively considered in studies of the built environment and obesity. Empirical results based on data from Atlanta, GA, USA, illustrate that the association between the built environment and obesity is sensitive to how age, income, and educational attainment are included in the model. Also, a detailed examination of land-use-mix measures shows that it is difficult to create this measure and that results are sensitive to the treatment of missing values. Models that distinguish between overweight and obese individuals are shown to provide richer insights into the associations among obesity, built environment, and sociodemographic characteristics for the Atlanta area. The article concludes by offering modeling recommendations for future studies.

Laurie A. GarrowEmail:

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Tudor D. Bodea   is a doctoral student in the School of Civil and Environmental Engineering at the Georgia Institute of Technology. His doctoral work examines the integration of customer-choice models into optimization algorithms for travel-industry applications. Laurie A. Garrow   is an assistant professor in the School and Civil and Environmental Engineering at the Georgia Institute of Technology. Her research addresses the development and application of advanced models of travel demand that integrate discrete choice, econometric, and market research methods to enhance understanding of travel behavior. Michael D. Meyer   is professor in the School of Civil and Environmental Engineering and Director of the Georgia Transportation Institute at the Georgia Institute of Technology. He has written over 160 technical articles and has authored or coauthored numerous texts on transportation systems, planning, and policy, including a college textbook. In 2006, he was the chairman of the Transportation Research Board Executive Committee. Catherine L. Ross   is Harry West professor in the City and Regional Planning Program and Director of the Center for Quality Growth and Regional Development at the Georgia Institute of Technology. She has published extensively in the fields of urban planning, transportation planning, and public participation. She is the coauthor of The Inner City: Urban Poverty and Economic Development in the next Century.