Food composition data: the foundation of dietetic practice and research.

Food composition databases and dietary assessment systems are important tools for food and nutrition professionals. The availability and accessibility of data have improved over time along with the technology to convert the information into useful formats for planning diets, writing educational materials, counseling patients, and conducting research. Primary sources of food composition data include government, academic, and other institutional databases; the food industry; and scientific literature. Changes in the marketplace affect food availability and composition and affect the accuracy and adequacy of food composition databases. Improvements in both food composition data and in dietary assessment methods have worked synergistically to improve estimates of dietary intake. The development of databases for food frequency assessment systems requires special considerations for data aggregation for each food or food grouping in the questionnaires. Considerations for selecting a dietary assessment system include appropriateness of the data for the intended audience or purpose, efficiency of the search strategy for retrieving data, content and format of summary information, and cost. Needs for food composition data vary depending on dietetic practice area; however, most food and nutrition professionals will benefit from becoming more informed about food composition data, exploring new ways to educate themselves about databases and database systems, and advocating for what is most needed in dietetic practice.