Social Distortion in Weight Perception: A Decomposition of the Obesity Epidemic

This paper examines the influence of social norms on obesity. We develop a concept of social norm related to social distortion in weight perception developed through shared experiences in a common social environment with a high prevalence of obesity. The theoretical model show that when obesity is common it less likely to be recognized as a problem by mitigating individual's health concerns. We prove that our empirical measures of such a social component are significant in influencing individual weight using regional data from the Health Survey for England. We use the marked difference in obesity rates between 2002 and 2006 to undertake a Fairlie decomposition analysis. Our findings suggest that when we exclude social norms our estimates explain less than 50% of the obesity gap. When we include the social norms our estimates explain between 50% and 80% of the overall obesity gap. By stratifying the result by gender we are able to prove that men are more susceptible to social distortion, especially the low-skilled. Medium- and low-skilled women, similarly, are more susceptible to environmental pressure than highly-skilled women, who result as being completely unaffected by it. Men are also affected by a broader set of environmental pressures, with respect to women. Overall, these results suggest that an individual's concern over his or her body weight is closely related to the actual weight of his or her reference network.