The result: An analysis of food receipts and post-meal surveys revealed that calorie guidance did not seem to help consumers better interpret or make overall better use of calorie labeling when it was present. Moreover, guidance failed to prompt a drop in the total number of calories informed patrons purchased.
Instead, those who received overall caloric information chose to eat slightly more calories, not fewer.
"It's just speculation," Downs said, "but I think what is going on is that people see the daily or per-meal calorie recommendations." She gave the example of a Big Mac, listed at 550 calories. "Which is actually not unreasonable. So then [customers] maybe feel OK to go ahead and get a slightly bigger main dish, but at the same time still get the same side dish and drink they would normally get. And then all of a sudden they're up over 1,100 calories for the meal. Each one item may seem OK, but it adds up," she noted.
"In the end the bigger issue is that asking people to do math three times a day every day of their lives is a lot," Downs added. "Because it's not like we make a decision about what to eat just once. It's a lot of decisions. And if you add a cognitive [mental] burden on top of that it's a lot to ask."
For her part, Lona Sandon, a registered dietitian and assistant professor of clinical nutrition at the University of Texas Southwestern Medical Center at Dallas, suggested that providing caloric information should be viewed as an important step towards building awareness, even if it doesn't immediately lead to better food choices.
"This continues to prove what those of us who work in the area of promoting healthy diets and lifestyles have known for years," Sandon said. "That is, knowledge does not equal or guarantee a change in behavior. Knowledge is just one piece of the puzzle. We must consider people's attitudes, beliefs and values surrounding healthier eating and body weight," she pointed out.
"The pros of choosing less calories must outweigh the cons," Sandon added. "In other words, they must see a benefit that is strong enough to outweigh the cons of a high-calorie meal that will be immediately satisfying and tasty," given, she said, that the number one reason people say they eat is for taste, not health.
Study author Downs said, "Now there is a reasonable argument to make that we should have these calorie labels and access to information. Certainly, for someone who's already health conscious, providing information and transparency is helpful. But the problem comes when we think that this is the solution to the obesity epidemic among the at-risk population we're trying to address."