How Will More Obesity and Less Smoking Affect Life Expectancy?

Personal behaviors can have a major influence on how long people live. Two especially damaging behaviors are smoking and the poor nutrition and exercise habits that result in obesity. Estimates from the Centers for Disease Control and Prevention suggest that, in 2000, 15 percent of U.S. deaths were caused by obesity and 18 percent by smoking. But obesity is on the rise while smoking is on the decline. The question is whether the benefits from less smoking will outweigh the harm from rising obesity. This brief, based on a recent study, projects how changes in obesity and smoking will impact life expectancy in 2040. The discussion proceeds as follows. The first two sections describe the methodologies for estimating the impact of obesity and smoking on mortality rates and for projecting how the prevalence of these behaviors will change over time. The third section presents the results, expressed as changes in future life expectancy. The final section concludes that, overall, the benefits of reduced smoking will trump the damage from increased obesity. However, the results differ by gender, with men showing a solid net gain, while women see only a small improvement. Length: 7 pages