Why are Americans more afraid of gaining weight than smoking cigarettes?

Which is a more serious problem for America, smoking or overeating? According to a Gallup poll released this week, 67 percent of the nation's adults think of cigarettes as an "extremely serious" or "very serious" social problem, compared with 81 percent who say the same for obesity. Gallup first started asking this question in 2003, and now, for the first time, respondents have shown that they're more worried about jiggly thighs than blackened lungs.

The idea seems to have made its way to Wall Street and Washington, too. Just this week, a group of equity strategists from Bank of America and Merrill Lynch proclaimed that "global obesity is a mega-investment theme for the next 25 years and beyond," and the Food and Drug Administration approved a weight-loss drug for the second time in two months—having finally calmed its nerves after the deadly fen-phen scandal of the late 1990s.

The shift in public opinion suggests a dangerous and unintended consequence of the war on obesity. Years of epidemiological work have shown that smoking is far worse for your health than being fat. So much worse, in fact, that any suggestion to the contrary should be taken as a sign that our priorities are getting all mixed up.