Will shortened life expectancy, caused by obesity, save social security?

Good economics webloggers like Brad DeLong and political webloggers like Talking Points Memo have been focused intensely on the social security privatization debate. Obesity arises comparatively rarely. But here's a tie-in. A new report from the New England Journal of Medicine seeks to estimate how much life expectancy will be shortened due to the obesity epidemic. News reports say some experts think the authors' actual quantitative predictions are overly dire, but their direction is surely right. A major epidemic of life-shortening disease should probably be considered as part of official computations about when social security will go bankrupt.

According to the AP coverage, the authors say obesity "likely will shorten the average life span of 77.6 years by at least two to five years. That's more than the impact of cancer or heart disease, said lead author S. Jay Olshansky, a longevity researcher at the University of Illinois at Chicago. This would reverse the mostly steady increase in American life expectancy that has occurred in the past two centuries and would have tremendous social and economic consequences that could even inadvertently help 'save' Social Security, Olshansky and colleagues contend."