It certainly seemed like a good idea: provide diners with recommended calorie information along with the calorie count of the meal they order. In practice, however, the additional information did nothing to change food choices. A new study by researchers at Carnegie Mellon University analyzed the food choices of more than 1,oo0 people who ate at two McDonald’s in New York. The diners were divided into three groups: One group was given only a recommended daily calorie intake in addition to existing menu labeling about calories per meal; one group was given a recommended per-meal calorie count in addition to existing menu labeling, and one group was given no additional information. How did that go? Not so good. A Carnegie Mellon news release reports that there was “no interaction between the use of calorie recommendations and the pre-existing menu labels, suggesting that incorporating calorie recommendations did not help customers make better use of the information provided on calorie-labeled menus. Further, providing calorie recommendations, whether calories per-day or per-meal, did not show a reduction in the number of calories purchased.