Food and dietary supplement databases for What We Eat in America-NHANES.

Relative strengths and potential approaches for improvement of food and dietary supplement databases used for tabulating intakes from the dietary component of the What We Eat in America-National Health and Nutrition Examination Survey (NHANES) are discussed. The U.S. Department of Agriculture's Nutrient Data Laboratory develops and maintains the Nutrient Databank System (NDBS) and many nutrient-specific and population-specific databases. NDBS contains data for approximately 8,000 foods and approximately 115 components; tables for compounds of special interest are also available. Nutrient databases need constant revision because of a constantly changing food supply. The completeness of analytical data varies from nutrient to nutrient. The National Center for Health Statistics developed and maintains a database of dietary supplements based on label information. To date, no verification of ingredients has been undertaken. The development of a dietary supplement database containing analytical values would require extensive resources but would be valuable. Databases for vitamin and mineral supplements are compatible with food databases. Databases for botanicals and other supplements include nonnutrient constituents that may not be documented in food composition databases. Gaps in food and dietary supplement composition data exist because of limited resources, changing availability of foods and products and the advent of new compounds of health interest. More data are needed on nutrients and other bioactive constituents in foods and dietary supplements. Analytical methods do not exist for all ingredients or active constituents in foods and dietary supplements. Research needs for further development of meaningful food and dietary supplement databases are similar.