Experts Weigh in on Calorie Lists on Menus, Despite “Mixed” Science

Experts Weigh in on Calorie Lists on Menus, Despite “Mixed” Science

Washington, DC – Scientific uncertainty exists about the benefits of requiring restaurants to prominently display calorie information on menu boards in the US, but key researchers in the field say that the obesity problem is so great that society needs to act now to increase awareness about the calorie content of these typically fast-food meals.

Presenting data during a special symposium at Obesity 2009, Dr Kelly Brownell (Yale University, New Haven, CT) likened the calorie labels to an exit sign in an office [1]. While not everybody uses the sign to find the way out and there is no evidence showing more people left the building after the sign went up, the consumer’s right to know about such information is important.

“My guess on this is that, at least in the foreseeable future, the science will be mixed,” said Brownell. “The question then is, Do we support menu labeling? Does it matter if it has an impact on calorie intake, or is it just a good thing to do? Over on that side of the room is the exit sign, and that provides you with information that could be helpful. My guess is that you don’t demand randomized controlled studies showing that that exit sign may be beneficial to your health and well-being. It’s information you believe you deserve.”

Similarly, Dr Lisa Harnack (University of Minnesota, Minneapolis), who presented data on the consumer use of labeling at fast-food restaurants and how much people eat when using that information [2], said there are conflicting results in the literature.

“I think if you put it all together, you might say that providing calorie information has a pretty weak or limited effect or perhaps no effect, and the question is why,” said Harnack. “One big question is that maybe people can’t relate to this calorie information. Maybe there is a need for more consumer education.”

The New York City experience

During a special session highlighting the impact of listing nutritional information on restaurant menus, experts remained upbeat about the laws mandating food labeling, despite the limited or conflicting data. It is hoped the labels will lead to individuals eating less calorie-rich, nutrient-poor foods, and this will ultimately decrease body weight among the general population.

As previously reported by heartwire, New York City made headlines in 2006 when the Board of Health and Mental Hygiene proposed eliminating partially hydrogenated vegetable oil, also known as trans-fatty acids, from restaurants around the city. The ban on trans fat eventually went through, affecting some 24 000 “food-service establishments.” Less attention, however, was paid to the decision to require these establishments to post the caloric content next to the listing of each food item on menu boards and menus. The new regulation was put into effect in March 2008 and was recently upheld in court.

Speaking during the Obesity symposium, Dr Lynn Silver, assistant commissioner of the board of health, discussed the New York experience, presenting two-year data obtained from more than 10 000 consumers dining at 13 food and coffee chains in 275 locations around New York City [3]. She noted that coffee chains accounted for roughly 40% of customers, followed next by hamburger chains, including McDonald’s and Burger King.

Preliminary findings, obtained from 2007 to 2009, showed that more people are seeing the calorie information, increasing to the point where more than half of individuals know the information posted on the menu board. Of these, 28% of individuals use the calorie information to guide their food decisions. Among fast-food consumers, roughly 16% reported using the information to make choices about what they eat.

Next up, the researchers wanted to determine whether the food labeling made any difference in the amount of calories people purchased. Silver said they did observe an overall “trend” toward lower calorie consumption in most restaurants, with consumers eating significantly fewer calories in four chains, including reductions at Starbucks, KFC, Au Bon Pain, and McDonald’s. The group noted that individuals seeing the calorie information and using it consumed roughly 100 calories less than those who didn’t see the information or chose to ignore it.

Interestingly, individuals who eat at Subway are consuming more calories, up 114 calories from 2007, a finding researchers attribute to “value pricing” the foot-long sandwich for five dollars.

“It actually became a very good economic decision for consumers to buy a 12-inch sandwich instead of the six-inch sandwich,” said Silver. “This suggests to us that when super sizes are actively promoted, it basically overcomes the effect of the additional information.”

Influence by calories vs actually eating less

Despite the fairly positive findings from Silver and colleagues, another recent study suggests that calorie information is not making a difference in people’s eating patterns. Comparing food choices in New York City with individuals who ate at similar restaurants in Newark, New Jersey, where there are no laws requiring calorie information, researchers found that 27.7% of the individuals saw the calorie labels and claimed the information influenced their choices, but there was still no difference in calories purchased between the two cities [4].

Similarly, researchers in Minnesota, led by Harnack, failed to show that posting caloric content on the fast-food menu during an experiment designed to mimic a fast-food experience had any effect on the calories consumed. While more than half the people noticed the information, it did not change what or how much they ate. Brownell, in a separate study, also showed evidence that individuals who eat less because of the calorie labels might simply be eating more later on at home unless the food information is contextualized, such as by teaching them to understand how many calories they should be eating daily.

Regardless, say experts, the decision by New York City, as well as other cities and states, to act against the growing obesity epidemic can be made “amid evolving and incomplete scientific knowledge” [5].

“I think the beauty of what New York City has done, and I consider the health department folks real heroes with this, is that they’ve set the stage for the government taking action in diet, nutrition, and obesity,” said Brownell. “Menu labeling is a great place to start. It makes all the sense in the world, and I suspect that when the story is told it will have a beneficial impact; we’ll just have to see. But it opens the door to other actions the government can take that might have an impact over the long term.”