Submitted to: International Food Data Base Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/14/2005
Publication Date: 7/14/2005
Citation: Bhagwat, S.A., Haytowitz, D.B., Harnly, J.M., Holden, J.M. 2005. Update of usda database for the flavonoid content of selected foods. International Research Conference on Food, Nutrition and Cancer on July 14 & 15, 2005 at Hyatt Regency Washington on Capitol Hill, Washington, D.C. Interpretive Summary:
Technical Abstract: Evidence to suggest an association of dietary flavonoids and reduction in cancer risk is consistent (Neuhouser, 2004). Flavonoids have also been associated with reduction in the risk of cardiovascular diseases (Huxley and Neil 2003). Reliable databases to estimate dietary flavonoid intakes are thus essential to study the health benefits and reduction in risks of chronic diseases. Nutrient Data Laboratory (NDL) of the U.S. Department of Agriculture (USDA) has developed databases for 3 different groups of flavonoids: monomeric flavonoids, polymeric proanthocyanidins and isoflavones. A database for monomeric flavonoids for 26 selected compounds in five subclasses (flavonols, flavones, flavanones, flavans and anthocyanidins) was released in March 2003. The database contained values for 225 selected foods. Most of the data came from the analytical studies conducted in the countries other than the United States. Therefore the NDL procured nationally representative samples of 59 fruits, vegetables and nuts through the National Food and Nutrient Analysis Program (NFNAP). It was also observed that analysts frequently concentrated on quantifying one or two particular subclasses of flavonoids for the lack of a suitable analytical method to separate and quantify all the five subclasses simultaneously. A kinetics method was developed by Merken, et al (2001) Food composition Laboratory (FCL) to separate and quantify 26 compounds representing all five subclasses. Food samples collected by the NDL through NFNAP were analyzed by FCL of the USDA using this method. The most significant finding from national sampling was the high degree of variability; an average RSD of 116% for composited samples or 197% for individual samples. These data will be incorporated into the revised database and released, on NDL’s website (www.nal.usda.gov/fnic/foodcomp). Additional, literature data published since 2002 were also collected and evaluated. Acceptable analytical data from approximately 90 studies have been or will be combined with the previous data. The new database will provide data on flavonols, flavones, flavanones, flavans and anthocyanidins for more than 400 selected foods and will be more representative of flavonoids content of U.S. foods and subsequent dietary intakes.