Shining light on fast food calories

Where's the data saying it might work? Anecdotal evidence gleaned from New York City, where a similar law has been in effect for about a month, is pretty dramatic, says Amanda Bloom, policy director at the California Center for Public Health Advocacy. "Diners are shocked at what they're seeing. And restaurants say they're selling out of their lowest calorie choices when they never were before."

Last year, before that law was in force, researchers analyzed the purchasing patterns of more than 7,000 customers at 11 fast-food chains in New York City for a study appearing this month in the American Journal of Public Health.

Then, only one of the 11 chains offered calorie-content information in a way that customers could easily see and use it. That was Subway, which provided the information on the splash guard between customers and the ingredients that go into their sandwiches -- so they could refer to it when they placed their orders.

(Calorie information at other chains was provided in less in-your-face locations such as in brochures or on websites.)

When surveyed, 32% of Subway's customers said they saw calorie information, and of those, 37% said the information affected their orders.

That means about 12% of all Subway customers said the information affected their orders.

Researchers compared the average calorie content in meals ordered by Subway customers who said they saw calorie information with customers who didn't, and found that those who said they saw the information ordered meals consisting of 714 calories, on average, versus 766 for those who said they didn't see it -- 52 fewer calories, or about a 7% reduction.

Then the researchers looked closer at the juicy details, finding that customers who saw calorie information and said it affected them ordered meals containing 647 calories, versus 746 for customers who saw the information and said it didn't affect them; in other words, they bought meals with 99 fewer calories, on average -- a 13% reduction.

Statistically speaking, the difference between those who saw information but ignored it and those who didn't see it at all is too small to count. Essentially, those who said it didn't affect them ordered like customers who didn't see the information.

Researchers conducting the just-released California study used the New York City results to project how many calories citizens here might avoid eating annually if the menu-labeling law gets passed.