Social dynamics of obesity

We explain the recent increases in obesity in the United States with a model involving falling food prices, endogenous social body weight norms, and heterogeneous human metabolism. Calibrating an analytical choice model to American women in the 30- to 60-yr-old age bracket, we compare the predicted weight distributions to National Health and Nutrition Examination survey data spanning (intermittently) the years 1976-2000. The model, the first to describe explicitly complete weight distribution dynamics for this group, predicts average weights and obesity rates with considerable accuracy and captures a significant portion of the recent growth in upper quantile weights.