Accuracy of Reported Energy Contents of Restaurant Foods?

Probably more calories than you imagine....

Do you ever wonder about the accuracy of calorie counts on restaurant food? Researchers recently examined and reported the accuracy of stated energy contents of foods purchased in restaurants.


The goal was to measure the difference between restaurant-stated and laboratory-measured energy contents.


A validated calorimetry technique was used to measure dietary energy (calories) in food from 42 restaurants. A total of 269 food items and 242 unique foods were assessed. The restaurants and foods were randomly selected from restaurants in Massachusetts, Arkansas, and Indiana.


Of the 269 food items, 50 (19%) contained measured energy contents of at least 100 kcal/portion more than the stated energy contents. Of the 10% of foods with the highest excess energy in the initial sampling, 13 of 17 were reanalyzed. In the first analysis, these foods contained average measured energy contents of 289 kcal/portion (95% CI, 186 to 392 kcal/portion) more than the stated energy contents; in the second analysis, these foods contained average measured energy contents of 258 kcal/portion (95% CI, 154 to 361 kcal/portion) more than the stated energy contents (P <.001 for each vs 0 kcal/portion difference). 


Foods with lower stated energy contents contained higher measured energy contents than stated, while foods with higher stated energy contents contained lower measured energy contents (P <.001).


Good news: stated energy contents of restaurant foods were (mostly) accurate overall.


Bad news:  there was inaccuracy for some individual foods. Low calorie food items may not be as low calorie as stated.


Vexing.