Social Interactions in Health Behaviors and Conditions

Abstract

Health behaviors are a major source of morbidity and mortality in the developed and much of the developing world. The social nature of many of these behaviors, such as eating or using alcohol, and the normative connotations that accompany others (i.e., sexual behavior, illegal drug use) make them quite susceptible to peer influence. This chapter assesses the role of social interactions in the determination of health behaviors. It highlights the methodological progress of the past two decades in addressing the multiple challenges inherent in the estimation of peer effects, and notes methodological issues that still need to be confronted. A comprehensive review of the economics empirical literature—mostly for developed countries—shows strong and robust peer effects across a wide set of health behaviors, including alcohol use, body weight, food intake, body fitness, teen pregnancy, and sexual behaviors. The evidence is mixed when assessing tobacco use, illicit drug use, and mental health. The article also explores the as yet incipient literature on the mechanisms behind peer influence and on new developments in the study of social networks that are shedding light on the dynamics of social influence. There is suggestive evidence that social norms and social conformism lie behind peer effects in substance use, obesity, and teen pregnancy, while social learning has been pointed out as a channel behind fertility decisions, mental health utilization, and uptake of medication. Future research needs to deepen the understanding of the mechanisms behind peer influence in health behaviors in order to design more targeted welfare-enhancing policies.

Weight, reference points, and the onset of eating disorders

“…A subset of students selected from the rosters of the sampled schools -about 20,000 individuals -was then asked 3 Our paper is also related to the studies examining peer effects in body weight (see, Yakusheva et al, 2014;Fortin and Yazbeck, 2015;Dieye and Fortin, 2017, for recent contributions), and to the wide literature looking at peer effects in obesity. See Balsa and Díaz (2018) for a recent review of this literature and Cawley (2015) for a review of the economic causes and consequences of obesity.…”