The researchers analyzed the calorie content of 18 side dishes and entrees from national sit-down chain restaurants, 11 side dishes and entrees from national fast-food restaurants and 10 frozen meals from supermarkets, and found the calorie content information provided by the restaurants was 18% less than the researchers’ calorie content analysis. The calorie content information reported by packaged food companies was 8% less than the researchers’ analysis.
“If people use published calorie contents for weight control, discrepancies of this magnitude could result in weight gain of many pounds a year,” said Susan B. Roberts, a professor at the Friedman School of Nutrition Science and Policy at Tufts University.
The study attributes the smaller discrepancy between the test results and the calorie content information from the frozen food companies to the Food and Drug Administration oversight of the Nutrition Facts information labels.
“We tested frozen foods straight out of their packages,” Ms. Roberts said. “For the restaurant foods we first calculated calorie content based on the portion we were served. When we went one step further and calculated calorie content based on portion size listed on the restaurant’s nutrition literature, the discrepancies between our results and the restaurant’s results decreased, which suggests oversized portions were part of the problem.”
The study also found five restaurants offered free side dishes that were not factored into calorie information provided for the entrees and that on average these side dishes contained more calories than the entrees they accompanied.