Are Network-Based Interventions a Useful Antiobesity Strategy?

Recent research has found that obesity tends to cluster in social networks, raising the possibility of using network-based interventions in anti-obesity strategies. This letter to the editor raises concerns about a recent analysis of the potential effectiveness of such strategies among simulated networks of adults in England. (El-Sayed AM, Seemann L, Scarborough P, et al. Are network-based interventions a useful anti-obesity strategy? An application of simulation models for causal inference in epidemiology. Am J Epidemiol. 2013;178(2):287–295). The letter points out that obesity status is not randomly distributed throughout social networks (as the simulation postulated) but clusters among socially connected individuals. Anti-obesity strategies will need to take this into account. If obese individuals are more likely to be socially connected to one another and marginalized in real-world networks compared with simulated networks, we may need a more a thorough understanding of diffusion, reinforcement, and social barriers of obesity prevention and treatment in social networks and the impact of this on population obesity rates.