More than 10 percent of the world's population is malnourished, but an even larger proportion is overweight. Greece has one of the highest rates of child obesity, despite having one of the world's healthiest cuisines.

A new study in the journal Lancet says lack of exercise now causes as many deaths as smoking. And according to the latest figures, obesity costs Americans about $200 billion a year in medical expenses. So perhaps it makes sense that for the first time, Americans polled by Gallup see obesity as a bigger problem than smoking or alcohol consumption.

LA Times columnist David Lazarus argues that government should intervene to curb obesity, because citizens cannot protect themselves from the deluge of advertising from the food and beverage industry.

Obesity is a recognized problem, but commentator Justin Wilson says it's a problem that's best solved by personal choices, not government intervention.