In the latest salvo in the obesity wars, a new paper in the American Journal of Epidemiology finds that being obese--even a little--raises your risk of death as you get older. This is contrary to the evidence of some earlier studies, such as this recent one, which found that being overweight or slightly obese was associated with a lower mortality risk.

The scientists behind the latest study--Ryan K. Masters,Daniel A. Powers and Bruce G. Link--point to selection bias as the flaw in previous studies. From the press release:

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