Obesity, physical activity and the neighborhood environment

Obesity is a major public health concern, though the numerous etiologic mechanisms that underlie this issue are poorly understood. While relationships between the neighborhood environment, physical activity and overweight have been hypothesized, additional research is needed to investigate these issues systematically in large, national datasets. In addition, this research must also account for numerous methodological complexities inherent in the assessment of these types of environmental exposures and health-related outcomes. Our research addresses these concerns, including both important conceptual and methodological contributions to the field by investigating the effect of the neighborhood's physical environment on activity patterns during adolescence, as well as subsequent weight change, and identifying areas for future environmental interventions aimed at promoting healthy behaviors. These analyses were conducted using the National Longitudinal Study of Adolescent Health, a nationally representative cohort of over 20,000 school-aged youth transitioning from adolescence into adulthood. Specifically, in this research we identified patterns in dimensions of the neighborhood environment, as well as physical activity and sedentary behaviors, using cluster analysis and related statistical techniques. We then used these multidimensional neighborhood patterns to predict patterns in physical activity, independent of individual characteristics. In addition, we examined the relationship between adolescent activity and the development of obesity in adolescence and young adulthood, independent of potential confounders such as physical or household environment and genetic predisposition, in a sub-sample of twin and non-twin siblings. This research fills an important gap in understanding of causal mechanisms underlying the development of obesity, as well as identifies areas for future environmental interventions promoting healthy behaviors.