Well, here's a groundbreaking new piece of evidence in the war against obesity: those calorie labels at fast food restaurants are only useful if you actually read them. Who would have thought?

According to a new study published in the BMJ Journal looking at the effects of New York's efforts to encourage healthy eating, the counts worked for a whopping one in six customers, or those who actually bothered to read them. People who don't read continued to order whatever they wanted. The study, which was the first large-scale report on the city's calorie counting initiative, looked at customers' lunchtime purchasing habits at 11 fast food chains, including McDonald’s, Au Bon Pain and KFC, over the course of three years.

Health Department officials view the study optimistically, saying it shows "modest gains in getting people to order lower-calorie meals" and also that the calorie-label law nudged restaurants into offering more healthy foods. Which is all well and good, but how useful can this study really be when calorie counts lie, anyway?