The Economics of Obesity

John Cawley

Cornell University and National Bureau of Economic Research

Research on Economics of Obesity

• Overviews of the economics of obesity

• Measurement of Obesity: – BMI overstates obesity in African Americans– Timing of epidemic of obesity varies by measure used to

track it– Encouraging social science datasets to collect more accurate

measures of fatness

• Causes of Obesity:– Income: negligible effect on weight of the elderly– Food advertising (in progress)

Research on Economics of Obesity• Consequences of Obesity

– Labor market outcomes: wages, employment, welfare to work, absenteeism, disability (generally worse for women than men)

– Medical costs– Risky behaviors: dating, sexual activity, smoking initiation among teens– Skill attainment of young children (2-3 yrs)

• Prevention and Treatment– Physical education classes (no effect on weight)– Financial rewards for weight loss (modest effects)– School-based interventions (mixed)– Nutrition labels (effective for white females)– Demand for anti-obesity drugs– Deceptive advertising of over-the-counter weight loss products– Predicting complications after bariatric surgery – What predicts state legislative action on childhood obesity– Voters’ willingness to pay for reductions in childhood obesity

How Informed by Other Fields

• Causes:– Genetics: relative contributions of genes, environment and interactions

– Sociology: peer effects

• Consequences:– Medicine: obesity-related comorbidities (suggest logical labor market

consequences)

– Sociology: assortative mating

• Treatment:– Psychology: departures from perfect rationality to explain failed

weight loss attempts, offer guidance on interventions

– Medicine: set points in weight, metabolism response to dieting

What Other Obesity Researchers Can Use From Economics

• Offers widely-accepted theoretical framework for human behavior (constrained maximization)

– Economics asks different questions, generates different predictions – focuses on role of incentives and tradeoffs

• Offers clearly-defined rationales for policy intervention – Fix market failures

• Offers useful methods for estimating causal effects (e.g. exploiting natural experiments)

– Determining causes and consequences of obesity– Determining what interventions or policies work– Which policies work best: cost-effectiveness analysis

What I’d Like to Learn From You

• I don’t even know the extent of what I don’t know

• What I know I don’t know:– Can individual alleles/genes be exploited as natural experiments?

– What are the true causal effects of obesity on specific aspects of health (as opposed to correlations that could be due to unobserved factors)?

– Contribution of brain chemistry to these behaviors

– More on response of metabolism, set points in weight

– More on psychology of delayed gratification / weight loss attempts

– What are you learning from ongoing interventions?

– What can we learn from research on other risky behaviors?