Restaurant, Packaged Foods Have More Calories Than on the Label
Many people rely on the Nutrition Facts label on packaged products to count calories, fat grams, or carbohydrate. However, a new study published in the Journal of the American Dietetic Association has found that the label could misrepresent the actual caloric content of the food inside.
Researchers from Tufts University evaluated the caloric content of 10 frozen meals purchased from Boston supermarkets and 29 quick-serve and sit-down restaurant foods from chain restaurants. The foods selected were primarily marketed as lower calorie foods for weight control with fewer than 500 calories per serving listed on the label. The foods were weighed, homogenized and ground into a fine powder, and then analyzed for energy content using a Bomb Calorimeter. Bomb calorimetry directly measures the heat of combustion, which gives a value for total energy in the form of kilocalories per gram, or “calories” as we know them on the food label.
The calories of the frozen foods averaged 18% more than what was listed on the Nutrition Facts label. The FDA allows for some discrepancy on food labels. Up to a 20% discrepancy is allowed for calories, but the product must almost exactly match the weight listed on the package. So manufacturers may add more food to meet the stricter weight guidelines. Also, if a product is calculated to consist of 203 calories, for example, it will likely be listed on the package rounded down to 200 calories, which is not likely significant to dieters.
Of the frozen meals tested, the products with the greatest discrepancies were the Lean Cuisine shrimp and angel hair pasta (319 calories vs 250 listed), Weight Watchers Lemon Herb Chicken Piccata (306 vs 252) and the Healthy Choice Chicken Parmigiana (431 vs 407).
The restaurant meals averaged 18% more calories, with seven of those exceeding the listed calorie level by 100%. In the fast food market, Taco Bell’s Express Taco Salad with chicken was listed at 326 calories but measured 607. The authors also measured some restaurant side dishes that were offered with the entrees. Denny's grits with butter, for example, was listed at 86 calroies, but measured at 258 in the calorimeter.
While the calorie discrepancy seems on the low end for most of the foods tested, just a 5% increase in calories per day can yield a 10-pound weight gain for someone consuming 2000 calories.
Source: “The Accuracy of Stated Energy Contents of Reduced-Energy, Commercially Prepared Foods” by Lorien E. Urban, MS; Gerard E. Dallal, PhD; Lisa M. Robinson, RD; Lynne M. Ausman, DSc, RD; Edward Saltzman, MD; and Susan B. Roberts, PhD. , Journal of the American Dietetic Association, Volume 110, Issue 1 (January 2010).