What is the USDA Food and Nutrient Database for Dietary Studies (FNDDS)?
The FNDDS is a database for processing and analyzing nationwide food consumption surveys and other dietary studies. The database includes descriptions of foods, their nutrient values, and weights for typical portion sizes.
How is FNDDS different from the Standard Reference (the USDA National Nutrient Database for Standard Reference)?
Purpose – The USDA National Nutrient Database for Standard Reference (SR) and FNDDS are designed for different purposes. SR is designed for the collection and dissemination of food composition data. FNDDS is designed for the coding and analysis of food consumption data.
Mixtures – The FNDDS data are for foods as consumed, and many of the foods in FNDDS are mixtures that are not available in the SR. SR is the source of the nutrient values for foods in FNDDS, including mixed foods whose nutrient values are calculated using SR items as ingredients.
Portion sizes – FNDDS portion weights are for the types of portion sizes that survey respondents report. For that reason, FNNDS includes additional weights for common food portion sizes that are not available in the SR.
Missing values – There are no missing values in the FNDDS. Documentation is included on how nutrient values for each food in the FNDDS were derived from SR.
How is FNDDS used?
To code and analyze nationwide survey data – FNDDS was designed for the purpose of processing dietary intake information collected in What We Eat In America, the dietary intake component of NHANES. Foods reported in What We Eat in America/NHANES are matched to food descriptions in the database and assigned the corresponding food code. Quantities of foods consumed are matched to portion descriptions and assigned the corresponding weights. Nutrient profiles in the database are used to calculate the nutrient contribution of each reported food quantity.
In other applications that rely on the information FNDDS provides on foods consumed by Americans – FNDDS has been used in the development of intake estimates based on Food Guide Pyramid servings. The database has also been used in the development of environmental exposure assessments, food frequency questionnaires, and dietary analysis software programs. For more information, see "Applications of the FNDDS."
Potentially, for numerous and varied analytical purposes – Researchers using What We Eat in America/NHANES data may wish to use FNDDS in their analyses. FNDDS can also be used with other dietary studies to code foods and amounts eaten and to calculate the amounts of nutrients in those foods.
How does FNDDS data differ from the food intake survey data?
The What We Eat in America/NHANES dietary intake data are based on 24-hour recalls collected using the USDA Automated Multiple-Pass Method. The dietary intake data are coded and analyzed using FNDDS data.
What are the differences between versions of the FNDDS??
For each numbered version of the FNDDS, a summary of changes since the previous version is provided in the documentation. Changes include foods, portions, weights, and nutrient values that were updated for processing dietary data from a 2-year release cycle of WWEIA/NHANES. Go to the main FNDDS page and click on "Changes From Previous Version" for the FNDDS version in question.
What nutrients are included in the FNDDS?
The list of nutrients and food components included in the FNDDS has increased over the years. Go to the main FNDDS page and click on "List of Nutrients/Food Components" for a given version of the FNDDS.
Where can I find the USDA Survey Nutrient Database?
The USDA Survey Nutrient Database (last available on the CSFII 1994-96, 1998 CD-ROM) was updated, redesigned, and renamed the USDA Food and Nutrient Database for Dietary Studies (FNDDS).
Why do most files in the database have the fields "Start Date" and "End Date?"
Each version of the FNDDS is a subset of the multi-year database (1994-2006) maintained by USDA's Food Surveys Research Group (FSRG). The multi-year database was designed to track changes in foods and facilitate analysis of intake trends. The date fields indicate the valid time period for a data record. The multi-year database may contain more than one record for the same food item, with different dates to indicate the different time periods when each value is valid. For example, for FNDDS 1.0, the "Start Date" for all records is 1/1/2001 and the "End Date" is 12/31/2002.
Can I identify foods by brand names in the FNDDS?
For some foods, it is possible. Brand names for many ready-to-eat cereals, infant formulas, and candies are assigned unique food codes in the database; these foods have unique nutrient profiles. Many brand names are linked to specific food codes to facilitate food coding for What We Eat in America/NHANES. These brand names have neither unique food codes nor separate nutrient profiles. Many portion descriptions in the database are brand specific, with unique weights.
How often will the FNDDS be updated? How will I know when you update the database?
FSRG plans to update and release FNDDS every two years in conjunction with data release from What We Eat in America/NHANES. Subscribe to the FSRG Listserv to receive announcements concerning updates of the database.