Tracking nutrient changes for trends analysis in the United States

Knowledge of food and nutrient consumption patterns over time is important to various types of research related to the health and well-being of the population. To ensure that food consumption trend analyses are meaningful, food databases must be updated frequently to incorporate the latest information. Systems should also be in place to categorize and track the types of changes that occur as food databases are updated. The Food Surveys Research Group at USDA has implemented a Survey Nutrient Database for Trends Analysis for use with food consumption surveys in the United States. Within this system, items may be added, or existing items may be revised. Data Improvements, such as new nutrient values representing improved analytical methods. replace existing values and may be applied retroactively to previous nutrient analyses. Revisions classified as actual Food Changes are inserted into the database, with older values remaining to represent the food items as they previously existed. Dates accompany each database value to indicate the time period for which it is valid. Since 1985, over 30 000 revisions have been made to the database nutrient values, Package sizes, portion weights, food names, and recipes used for nutrient calculations are also tracked within the system. (C) 2001 Academic Press.