Disciplines as diverse as economics, sociology, medicine, computer science, political science and physics have recently become interested in the interdependence of behaviours across the human social network. In particular, scientists have begun to ask whether our health and other behaviours are contagious, in that our decisions and actions affect the decisions and actions of our peers. If behavioural contagions exist, understanding how, when and to what extent they manifest in different behaviours will enable us to transition from independent intervention strategies to more effective interdependent interventions that incorporate individuals’ social contexts into their treatmentsA new study offers some of the first hard evidence that health-related habits can spread — and so perhaps could be deliberately seeded and encouraged — by social influence and peer pressure. Previous research has sought such a contagious effect in factors such as obesity and smoking, but the results have been inconclusive.
Studies in social differences in health have a a new hurdle to tackle. How to boost social permeability? As Mackenback said in The Lancet on health inequalities: now it's personal.
PS. These are the results of the study in one figure: