The new study follows on from previous research, which already suggest that people eat less when confronted with the calorie count of their food, but scientists are now taking this a step further.
People were selected at random on the Oklahoma State University campus, to dine from one of three menus over a two-week period in late 2010. One group received menus with no calorie or nutrition information, another received one displaying each menu item’s calorie count, and the third group received a menu featuring traffic light symbols representative of calories; green meant there were less than 400 calories present, yellow represented 401 and 800 calories, and red signified over 800 calories.
The study found that diners who had ordered off the standard menu consumed more than 817 calories compared to the 765 calories that people ate off the menu featuring the calorie count, and 696 off the menu featuring traffic lights.
While in theory, this is only a difference of 52 calories and 121 calories between the standard and experimental menus, the study’s lead author said that can add up over time.
Depending on the person, 121 calories per day could result in one pound (almost half a kilogram) of weight loss per month.
“It could be substantial if that reduction persists every time you went out to eat, but as a one term reduction it might not be effective,” said Brenna Ellison, of the University of Illinois at Urbana-Champaign.
Ellison told Reuters Health that while the health conscious among us are already more nutrition and calorie aware and hence won’t benefit as much from the new menu format, it is the least health-conscious who will benefit the most, and these are “precisely the people that menu labelling laws are often trying to influence.”