The Engineering Economist, 51: 307–323 Copyright © 2006 Institute of Industrial Engineers ISSN: 0013-791X print / 1547-2701 online DOI: 10.1080/00137910600987586 THE ECONOMIC IMPACT OF OBESITY ON AUTOMOBILE FUEL CONSUMPTION Sheldon H. Jacobson Department of Computer Science, Simulation and Optimization Laboratory, University of Illinois, Urbana, Illinois, USA Laura A. McLay Department of Statistical Sciences and Operations Research, Virginia Commonwealth University, Richmond, Virginia, USA Obesity has become a major public health problem in the United States. There are numerous health implications and risks associated with obesity. One socio-economic implication of obesity is that it reduces passenger vehicle fuel economy (i.e., the miles per gallon achieved by automobiles, which include cars and light trucks driven for noncom- mercial purposes). This article quantifies the amount of additional fuel consumed (annually) in the United States by automobiles that is at- tributable to higher average passenger (driver and non-driver) weights, during the period from 1960 to 2002. The analysis uses existing driv- ing data in conjunction with historical weight data. The results indi- cate that, since 1988, no less than 272 million additional gallons of fuel are consumed annually due to average passenger weight increases. This number grows to approximately 938 million gallons of fuel when mea- sured from 1960, which corresponds to approximately 0.7% of the na- tion’s annual fuel consumption, or almost three days of fuel consumption by automobiles. Moreover, more than 39 million gallons of fuel are esti- mated to be used annually for each additional pound of average passenger weight. Address correspondence to Sheldon H. Jacobson, Department of Computer Science, Simula- tion and Optimization Laboratory, University of Illinois, 201 North Goodwin Avenue (MC-258), Urbana, IL 6180: E-mail: shj@uiuc.edu