NBER WORKING PAPER SERIES

THE LONG-RUN GROWTH IN OBESITY ASA FUNCTION OF TECHNOLOGICAL CHANGE

Tomas J. PhilipsonRichard A. Posner

Working Paper 7423http://www.nber.org/papers/w7423

NATIONAL BUREAU OF ECONOMIC RESEARCH1050 Massachusetts Avenue

Cambridge, MA 02138November 1999

The authors thank Gary Becker, John Cawley, D. Gale Johnson, Lars Lefgren, Casey Mulligan, IgnacioPalacios-Huertas, Eric Posner, Allen Sanderson, and George Zanjani for very helpful comments. The viewsexpressed herein are those of the authors and not necessarily those of the National Bureau of EconomicResearch.

© 1999 by Tomas J. Philipson and Richard A. Posner. All rights reserved. Short sections of text, not toexceed two paragraphs, may be quoted without explicit permission provided that full credit, including © notice,is given to the source.

The Long-Run Growth in Obesity as a Function ofTechnological ChangeTomas J. Philipson and Richard A. PosnerNBER Working Paper No. 7423November 1999JEL No. I1

ABSTRACT

This paper analyzes the factors contributing to the worldwide long-run rise in obesity and the

effects of public interventions on its continued growth. The growth of obesity in a population results from

an increase in calorie consumption relative to physical activity. Yet in developed countries, obesity has

grown with modest rises in calorie consumption and with a substantial increase in both dieting and

recreational exercise. We consider the economic incentives that give rise to a growth in obesity by

stimulating intake of calories while discouraging the expending of calories on physical activity. We argue

that technological change provides a natural interpretation of the long-run growth in obesity despite a rise

in dieting and exercise, that it predicts that the effect of income on obesity falls with economic development,

and that it implies that the growth in obesity may be self-limiting.

Tomas J. Philipson Richard A. PosnerIrving B. Harris Graduate School of Public Policy Studies Law SchoolDepartment of Economics and The Law School University of ChicagoUniversity of Chicago 1160 East 60th Street1155 E. 60th Street Chicago, IL 60637Chicago, Il 60637 richard_posner@ca7.uscourts.govt-philipson@uchicago.edu