Excerpt: Americans are getting fatter. One in five Americans is obese; three in five are either overweight or obese. The obesity rate has accelerated dramatically in the past 20 years, in conjunction with a national trend toward sedentary lifestyles.... Two RAND researchers, health economist Roland Sturm and psychiatrist Kenneth Wells, examined the comparative effects of obesity, smoking, heavy drinking, and poverty on chronic health conditions and health expenditures.  MORE >>