Study Links Obesity And A Society's Wealth Gap

What makes Americans so fat? Don't blame the doughnuts. That extra heft could be symptomatic of a malaise prevalent in all the world's least equal societies. According to "The Spirit Level," a new book by British academics Richard Wilkinson and Kate Pickett, a slew of social woes—from drug abuse to obesity and mental illness—can be tied directly to the width of a nation's income gap.

The evidence for the link is compelling. Obesity is six times more common in America, where the wealth gap is among the highest in the developed world, than in Japan at the opposite end of the inequality scale. And teenage birthrates in Britain are at least five times higher than in the more egalitarian Netherlands.

The explanation lies in a highly evolved reaction to low status, which shows itself in misery, violence or poor self-esteem. Weight, in particular, has long been a marker of socio-economic clout, and there's an unusually close match between obesity in women and their society's wealth gap. But it's not only the poor who suffer in unequal societies; higher incidences of mental illness, for example, affect all classes.

Still, with diagnosis comes the chance for a cure. "This suddenly gives us a handle on the psychosocial well-being of whole populations," says Wilkinson. Individuals should cut down on calories; meanwhile, governments should seek a slimmer wealth gap.