Dietary intake methodology. II. USDA's Nutrient Data Base for Nationwide Dietary Intake Surveys.

The U.S. Department of Agriculture's (USDA) Nutrient Data Base for Nationwide Dietary Intake Surveys is specifically organized and maintained to analyze data from nationwide dietary surveys within the federal government's National Nutrition Monitoring System. These surveys include the Nationwide Food Consumption Survey and the Continuing Survey of Food Intakes by Individuals conducted by USDA, and the National Health and Nutrition Examination Survey conducted by the Department of Health and Human Services (DHHS). Each public release of the data base covers one or more specific surveys. The data base contains data for energy and 28 components for over 5000 food items. Data are based on the latest information from USDAs National Nutrient Data Bank, the computer-based system used to update USDAs standard reference on food composition, Agriculture Handbook No. 8. An automated system is also used to update the survey nutrient data base with new information released from the Nutrient Data Bank. This system includes three supplementary data sets (primary nutrient data set, recipe file, and table of nutrient retention factors) and a computer program for calculating nutrient content of mixed food items based on nutrient content of their ingredients. Updates are performed at the beginning of new surveys to incorporate the most up-to-date nutrient values.