Researchers at Duke University and the University of Southern California conducted experiments testing the effectiveness of calorie labeling on menu boards for servings of food.
Some question if menu board calorie ranges help consumers make accurate calorie estimates because some of the ranges are very large.
The study, published in the journal Public Health Nutrition, found 326 Chipotle customers guessed their burritos were about 630 calories each when they were closer to 900 calories.
Chipotle said their restaurants have a harder time complying with the calorie labeling requirement because they customize food servings to the customer's requests.
“Putting calorie counts on things is super easy when it’s a packaged product and it’s made exactly the same every time or it’s a restaurant where you order a number one and always get exactly the same thing," Chris Arnold, Chipotle’s communications director, told Time magazine.
"The degree to which people may misestimate calories is really a product of a menu labeling law that doesn’t work so well for a restaurant like ours."
The researchers found consumers tended to think of the low end of the burrito range of calories as the "healthiest" version, while the restaurant chain said the burrito with the fewest ingredients was at the low end of the calorie range.
For instance, the burrito range started with a tortilla and pinto beans, instead of lower calorie black beans.
“We recognize it’s not ideal, but there’s not really a better way to do it when you can put it together in so many different ways,” Arnold said.
The study found calorie range information on menu boards improved calorie estimation accuracy, but deﬁning the meaning of the end points -- high and low calorie ends -- further improved accuracy.
"We suggest that when restaurants present calorie range information to consumers, they should explicitly deﬁne the meaning of the end points," the study authors said.