Flavonoid Content of Selected Dietary Supplements and Foods
Food Composition and Methods Development Lab
Project Number: 1235-52000-060-21
Interagency Reimbursable Agreement
Start Date: Sep 01, 2013
End Date: Aug 31, 2015
The two-year study is designed to improve the estimates of flavonoid contents in dietary supplements and to develop retention factors for processed and prepared foods. This information is critical for accurately predicting total flavonoid dietary exposures by humans in the NHANES and other population-based surveys. The expansion of knowledge about flavonoids in dietary supplements will enhance abilities to more accurately evaluate total intakes of this class of bioactive food constituents. In addition, this study will serve to verify or correct numerous assumptions about the effects of processing and preparation on flavonoid content that were made while expanding the “USDA database for the flavonoid content of selected foods, Release 3.1” for the Food and Nutrient Database for Dietary Studies (FNDDS) 4.1 that will be used to estimate flavonoid intakes by the U.S. population.
Flavonoid-containing dietary supplements will be identified for purchase using data from recent NHANES dietary supplement files and information from the 2011 Nutrition Business Journal report. Multiple lots of 40 top selling products from 3 market channels will be obtained. A list of top selling flavonoids containing dietary supplements is currently being developed based on market share information from NHANES and sales volume information from the Nutrition Business Journal. Products with and without specific labeled levels of flavonoid ingredients will be analyzed. Concentrated single ingredient products, as well as supplements containing relatively un-processed dried plant materials, will be analyzed. Additional factors, including prioritized flavonoid classes based on check sample results and flavonoid ingredient rankings on product ingredient lists will be researched to determine the specific criteria for products in this study.