USDA database for the flavonoid content of selected foods, Release 3.1

Authors: Bhagwat, Seema; Haytowitz, David; HOLDEN, JOANNE - Retired ARS Employee

Submitted to: Home Page
Publication Type: Research Technical Update
Publication Acceptance Date: 6/5/2013
Publication Date: 6/5/2013
Citation: Bhagwat, S.A., Haytowitz, D.B., Holden, J.M. 2013. USDA database for the flavonoid content of selected foods, Release 3.1. Home Page. http://www.ars.usda.gov/Services/docs.htm?docid=6231.

Interpretive Summary: The scientific community, the media and the general public are interested in the flavonoid content of foods because of their purported beneficial health effects. The Nutrient Data Laboratory (NDL) of ARS/USDA released the 2nd update of the “USDA Database for the Flavonoid Content of Selected Foods, Release 3” in September 2011 to enhance the representation of the U.S. foods in the database by adding the data from 100 scientific articles published since the last release. It contained data for 500 foods. The foods were organized by “Food Groups” instead of in alphabetical order. Data are presented for five subclasses of flavonoids: flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins. The mean, standard error, minimum and maximum values per 100g edible portions (mg/100g) with confidence codes (data quality) and sources (references) are provided. The database is available on NDL’s web site: http://www.ars.usda.gov/nutrientdata. The foremost reason to publish the Release 3.1 is the addition of a separate table of individual data records (more than 24,000 data points) used to create the mean values from the aggregated data. This table would be useful to the researchers studying absorption of the flavonoids. Six new foods (table olives, olive oil) were also added to the Release 3 bringing the total number of foods in the Release 3.1 to 506 foods, more than doubling the number of foods in the database since the first release. Some calculations were also revised. Varieties of fruits (apples, berries, citrus fruits etc.), vegetables (onions, lettuce, peppers etc.), beverages (teas, wines) and chocolates are included in the database. The database includes source documents citing research conducted in the U.S. and also in 50 other countries. Other flavonoids such as isoflavones (daidzein, genistein and glycitein) and proanthocyanidins (dimmers, trimers, 4-6mers, 7-10mers and >10 polymers) are not included in this database, but were released earlier as separate databases and are available on NDL’s web site. Combined, these three databases will provide reliable values for epidemiological studies to assess the relationship between flavonoid intakes and health benefits. The databases have been used in more than 50 epidemiological studies to estimate flavonoid intakes (~13) and to assess relationship between flavonoid intakes and different cancers (~20), cardiovascular diseases (~9) and other studies in Europe (European Prospective Investigation into Cancer and Nutrition and other studies) and the U.S.

Technical Abstract: Interest of the scientific community in the types and levels of flavonoids in foods continues because of consistent evidence regarding beneficial effects of dietary flavonoids. Flavonoids, particularly flavan-3-ols and proanthocyanidins, have been associated with the reduction in the risk of cardiovascular diseases by modulating various mechanisms of primary and secondary prevention such as modulating blood pressure, vascular inflammation, and endothelial-dependent vasomotor function. The association of reduced risk of cardiovascular diseases and flavonoids appears to be stronger than that for the inhibition of cancer, although some evidence for the reduction of some organ-specific cancers, such as lung and stomach, has been reported. The Nutrient Data Laboratory (NDL) of ARS/USDA released the 2nd update of the flavonoids database, “USDA Database for the Flavonoid Content of Selected Foods, Release 3” in September 2011 to enhance the representation of the U.S. foods in the database by adding the data from 100 scientific articles published since the last release (Release 2.1). It contained data for 500 foods. Foods were organized in “Food Groups” instead of in alphabetical order. The database contains values for 26 monomeric compounds in five subclasses of dietary flavonoids: 1) flavonols (isorhamnetin, kaempferol, myricetin, quercetin), 2) flavones (apigenin, luteolin), 3) flavanones (eriodictyol, hesperetin, naringenin), 4) flavan-3-ols ( (+)-catechin, (-)-epicatechin, (-)-epicatechin 3-gallate, (-)-epigallocatechin, (-) epigallocatechin 3-gallate, (+)-gallocatechin, theaflavin, theaflavin 3-gallate, theaflavin 3’-gallate, theaflavin 3,3’-digallate, thearubigins), and 5) anthocyanidins (cyanidin, delphinidin, malvidin, pelargonidin, peonidin, petunidin). All the values are reported as aglycones of compounds except for catechins and theaflavins which exist as gallate esters, predominantly in tea. The mean, standard error, minimum, and maximum values per 100g edible portion (mg/100g), number of samples, confidence codes for data quality and references from where the values were obtained are reported for each compound in every food. The database is available on NDL’s website: http://www.ars.usda.gov/nutrientdata. The database includes source documents citing research conducted in the U.S. and 50 other countries. The foremost reason to publish the Release 3.1 is the addition of a separate table of the individual data records used to create the mean values from the aggregated data. This table contains more than 24000 data points. It includes source of the data point (reference number), Nutrient Data Bank numbers (NDB), food descriptions, analytical method, values of flavonoid compounds and units as reported in the original article, conversion factors used to convert glycosides into aglycones, and other factors such as moisture or specific gravity to report all the values as mg/100g as aglycones. This table would be useful to the researchers interested in different glycosidic forms of the flavonoids since these forms are considered to influence the bioavailability. The Release 3.1 also contains data for six new foods (different kinds of olives, olive oil and additional data on rabbiteye blueberries) from eight new articles bringing the total number of foods to 506 and the total number of resources (references) to 308. A number of revisions were made to the inadvertently used wrong conversion factors (glycoside to aglycone and unit conversions to mg/100g). Other flavonoids such as isoflavones (daidzein, genistein and glycitein) and proanthocyanidins (dimmers, trimers, 4-6mers, 7-10mers and >10 polymers) are not included in this database, but were released earlier as separate databases and are available on the NDL web site. Combined, these three databases will provide reliable values for epidemiological studies to ass