The Long-Run Growth in Obesity as a Function of Technological Change

This paper analyzes the forces contributing to the worldwide long-run rise in obesity and the role of public interventions in affecting its continued growth. The cause of a growth in obesity in a population must be that calorie consumption is outpacing the growth of physical activity. Yet in developed countries, obesity has grown with modest rises in calorie consumption and with a substantial increase in both exercise and dieting. We consider the economic incentives that give rise to a growth in obesity by stimulating intake of calories at the same time as discouraging the expending of calories on physical activity. We argue that technological change provides a natural interpretation of the long-run growth in obesity, that it predicts that the effect of income on obesity changes sign with economic development, and that it implies that the growth in obesity may be self-limiting.