Read between the lines: If the calorie count seems too good to be true, the number's probably wrong.

RODALE NEWS, EMMAUS, PA—With obesity rates skyrocketing, it’s time to get real about the amount of calories we ingest, whether at home or on the go. And since Americans get approximately 35 percent of their daily caloric intake from food eaten in restaurants, knowing just how many calories are in restaurant food is vital—which is why posting calorie counts on restaurant menus is a good idea. But can we trust those calorie listings? In a recent study, Tufts University researchers found that overall, the stated calories of items on restaurant menus are accurate. But they also found that there are a lot of understated calorie figures for the so-called low-cal dishes on menus.

THE DETAILS: The study of calories in restaurant food, published in the Journal of the American Medical Association, examined the calorie content of food from about 40 fast-food and sit-down restaurants in three states. Of the 269 food items analyzed, 40 percent had at least 10 calories per portion higher than the stated calories, and 52 percent had at least 10 calories/portion lower than the stated calories. And 19 percent of foods contained greater than 100 calories/portion more than the stated calories. The researchers found significantly greater discrepancies between the stated and measured calories in foods from sit-down restaurants, compared with foods from fast-food restaurants. And in an analysis of the 10 foods with the greatest discrepancy between measured and stated calories, these foods on average measured 273 calories/portion higher than the stated calories, a 48 percent discrepancy.

Study author Susan B. Roberts, PhD, says that the important takeaway here is that the lower-calorie foods ordered in sit-down restaurants—the foods that are mainstays of dieters and people watching their weight—had significantly more calories than what was listed. Says Roberts, “The difference was quite large. For example, an entrée listed at 300 calories would typically have about 400 calories, based on the results of this study. That is an amount that, if consumed extra every day, adds up to 10 to 15 pounds of weight gain a year!” Roberts and her colleagues were surprised to find that salads and soups—both foods favored by weight-conscious diners—were the most likely to be listed inaccurately. “Pizza was actually the most accurate (for individual pizzas), turning conventional wisdom about salads being the safe choice on its head,” added Roberts.