Would posting calories help?

For lunch today I had onions, peppers, carrots, broccoli and cucumbers grilled in a little olive oil. It was fine; tasted good. But I topped it off with some sugar-free peanut butter chocolate ice cream. The calories were posted on the carton. And I ate it anyway.

Will posting calories prominently really make Americans think twice and order more healthy items? "Anecdotally, you hear constantly about people who've changed their choices," say [New York City] Commissioner Frieden. "You go into fast-food places and you hear a lot of buzz online."

Elisabetta Politi, director of nutrition at the Duke Diet & Fitness Center, isn't so sure. "Some of our clients know so much about nutrition they could teach the classes, but does that help them control their weight? Absolutely not," she says. From WSJ Health Journal

The editor of this story needed to find a different photo to show how rising prices for food are hurting people.