The built and social neighborhood environment and child obesity: A systematic review of longitudinal studies

The built and social neighborhood environment where a child lives has been increasingly studied as an exposure that may affect child weight long term. We conducted a systematic review of primary research articles published in 2011 through 2019 that reported results from longitudinal analyses of associations between neighborhood environment characteristics and child obesity or weight. Neighborhood environment measures included proximity to food stores, parks, and recreational facilities, walkability, crime, perceived safety, and social cohesion. Information on study population, exposure and outcome measures, and main results were extracted from 39 studies and results were presented for full cohorts and stratified by sex. Most studies were prospective cohorts (90%) with a median follow-up time of six years. Studies analyzing changes in the neighborhood versus changes in weight were less common than approaches analyzing baseline measures of the neighborhood environment in relation to obesity incidence or weight trajectories. Associations varied by sex, race/ethnicity, and age group. Within the food environment domain, the strongest evidence of adverse impact was for fast food restaurants but the effect was only apparent among girls. Results suggested green space, parks, and recreational facilities may have a beneficial effect on weight. Increased crime and low perceived safety may be risk factors for increased weight although not all studies were consistent. Standardization of measures across studies, investigation of multiple social and physical environment measures simultaneously, effect modification by demographic characteristics, and change in the environment vs change in weight analyses are needed to strengthen conclusions.