How accurate are reported energy contents of prepared foods in restaurants and supermarkets in the US?

Abstract

Recent media reports suggest that restaurants may substantially under‐report the energy contents of typical menu items. We examined the accuracy of reported energy contents of 31 items from fast food and chain restaurants and 10 supermarket frozen meals in Massachusetts suitable for weight loss based on their low energy contents posted on websites. Food was analyzed for gross energy (GE) content using a validated bomb calorimetry system accurate to ±1.9% for individual food samples and values were compared to reported information normalized to equivalent GE content. Mean reported energy for restaurant foods and supermarket meals were respectively 16% and 8% higher than reported values, and some individual restaurant items were up to 100% greater than reported energy. When free side dishes were provided and included in the comparison, mean provided energy was 245% of reported values for the purchased items. These findings suggest a tendency for restaurants to under‐report meal energy content, and highlight the major impacts that variability in reporting accuracy and free side dishes have on provided energy. Further studies are needed to determine the extent of underreporting of energy, which has implications for both emerging policy initiatives requiring reporting of food energy at the point of purchase and individual efforts to use provided information for self‐monitoring for weight control.Grant Funding SourceNIH grant HL069772‐06 and the USDA under agreement no. 58‐1950‐4‐401