Calories underestimated in "healthy" restaurants

NEW YORK (Reuters Health) - People who opt for a meal at a "healthy" restaurant often consume more calories than they would dining at fast food joints that make no health claims, a new study shows.

The researchers found that individuals underestimate the calorie content of foods served at restaurants they see as healthier, to a degree that could easily lead to weight gain.

For example, "People think that the same 1,000-calorie meal has 159 fewer calories if it comes from Subway than if it comes from McDonalds," Dr. Pierre Chandon, at INSEAD in Fontainebleau, France, told Reuters Health. "If they choose to consume this fictitious 'calorie credit' on other food, and it they eat at Subway twice a week, they could gain an extra 4.9 pounds a year."

While restaurants presenting themselves as healthy have grown at a much faster rate over the past five years than traditional fast food restaurants, Americans' waistlines have not been shrinking; in fact, the nation's population is fatter than ever, note Chandon and his colleague Dr. Brian Wansink of Cornell University in Ithaca in their report in the Journal of Consumer Research.

The researchers theorized that people might take in more calories when they eat in "healthy" restaurants, and conducted a series of studies to test this notion.

In the first, they asked people who had just finished eating at Subway or McDonalds to estimate how many calories they had just consumed. On average, Subway patrons rated their meals as having 151 fewer calories than did McDonalds patrons. In fact, for a meal at either restaurant containing 1,000 calories, people would estimate it to contain 744 calories if they'd eaten at McDonalds and 585 calories if they'd dined at Subway.

In the second experiment, they asked people to estimate the calorie content of four different sandwiches: a six-inch ham and cheese sandwich (330 calories) and a 12-inch turkey sandwich (600 calories) from Subway; and a McDonalds cheeseburger (330 calories) and a Big Mac (600 calories). Study participants consistently rated the Subway sandwich as having fewer calories than the McDonalds sandwich with the same calorie content.

Next, the researchers offered people a coupon for a Big Mac (600 calories) or a Subway 12-inch Italian BMT sandwich (900 calories), and asked them whether they would like to order a drink or cookies with their sandwich. People eating the Subway sandwich were more likely to choose a large drink, less likely to opt for diet soda, and more likely to get cookies. This meant that, on average, they wound up consuming 1,011 calories, compared to 648 calories for the people given a McDonalds coupon.

People who want to control their weight or trim down need to think objectively about calorie content, and not let their perceptions be clouded by whether a food is supposed to be good or bad for them, Chandon said. "We have to move away from thinking of food in 'good food / bad food' (terms) and think also about 'how much food.' In France, for example, people enjoy relatively fat diets but are less overweight simply because portion sizes in restaurants and at home are smaller."

Chandon suggested one technique to help people judge calorie counts more accurately: "Instead of estimating the number of calories of the whole meal (which leads to undercounting) look at the sandwich, the side, the beverages, and the drink and add that up. Our research showed that this 'piecemeal' method is very effective."

SOURCE: Journal of Consumer Research, October 2007.