We Americans are terrible at estimating how many calories we’re taking in when we’re eating out, particularly if we think a restaurant serves healthy food, a new study has found. In fact, in one of the study’s experiments, people eating at restaurants deemed “healthy” thought they were eating only 56 percent as many calories as they actually did.
These results may help explain the “American obesity paradox” — the observation that as the popularity of healthier foods (fewer calories, less fat) expands, so does the size of America’s waistlines.
“[O]ur findings show that the public health benefits of healthier foods are at least partially negated by the halo effects of health claims that lead people to order calorie-rich side dishes and beverages,” wrote the study’s authors, Pierre Chandon of INSEAD busines school and Brian Wansink of Cornell University.
But all is not lost. The study also found that if we stop and think about whether a meal is actually low in calories, despite what it’s called or where it’s served, we’re much better at making more healthful choices.
Here are the details of the study, which appears in the October issue of the Journal of Consumer Research. It included four experiments:
The first experiment began with researchers asking 49 regular customers of McDonald’s and Subway to rate (on a 9-point scale) how healthy they thought the food being served there was. Subway meals were rated significantly healthier (undoubtedly due to the hugely successful television ad campaigns starring “Subway dieter” Jared Fogle).
Next, the researchers asked 265 diners at McDonald’s and 253 at Subway to estimate the number of calories contained in a meal they had just purchased. Subway’s “health halo effect” (consumers’ belief that it serves healthier foods) led its customers to mistakenly estimate that a 1,000-calorie Subway meal contained 21 percent fewer calories than the same-calorie meal at McDonald’s.
In a second experiment, the researchers asked 316 regular Subway and McDonald’s patrons to estimate the number of calories contained in two Subway sandwiches and two McDonald’s burgers. (One meal from each restaurant contained 330 calories; the other, 600 calories.) Participants were also asked to rate how much attention they pay to nutrition in their food choices and whether calorie amounts affect those choices.
The experiment found that no matter how nutritionally aware people rated themselves, they still significantly underestimated the number of calories in the Subway meals. The “health halo effect” remained a factor.
In a third experiment, 46 undergraduate students were given a coupon good for either a 600-calorie McDonald’s Big Mac sandwich or a 900-calorie Subway 12-inch Italian BMT sandwich. Participants were then asked if they’d like to order a regular fountain drink (containing 155, 205, or 310 calories, depending on size), a diet fountain drink (zero calories) or one or two chocolate chip cookies (220 calories each).
Even though the “healthy” Subway sandwich contained 50 percent more calories than the Big Mac, participants who chose it also chose higher-calorie drinks and cookies containing up to 131 percent more calories.
But here comes the good news: In the final experiment, the researchers were able to eliminate the “health halo” and get participants to give more accurate calorie estimates by asking them to “consider the opposite” — specifically, to think about how a 660-calorie meal (a 6-inch Italian bologna sandwich and a 20-ounce glass of Coca-Cola) from “Good Karma Healthy Foods” may not be a typical healthy item from that restaurant.
“Our findings suggest that [a] worthy public policy effort may be to help people to better estimate the number of calories they consume,” the study’s authors concluded. “There is nothing wrong with occasionally enjoying a high-calorie meal as long as people recognize that they have had a lot of calories and that they need to adjust their future calorie intake or expenditure accordingly.”
Meanwhile, said Wansink in a prepared statement, you can take a simple action to make sure you’re not hoodwinked by the health halo effect the next time you eat out: “If you’re eating at what you think is a healthy restaurant, take your best estimate of the calories in the meal — and double it. You’ll be a lot more accurate.”