title: Flavonol and flavone intakes in US health professionals.
abstract: OBJECTIVE
  To determine flavonoid content of US foods, mean individual intakes, major food sources, and associations with other nutrients.
  
  
  METHODS
  US men (n = 37,886) and women (n = 78,886) who completed a semiquantitative food frequency questionnaire in 1990.
  
  
  METHODS
  Men and women completed a questionnaire that listed 132 items, including onions as a garnish and as a vegetable, rings, or soup. Foods known to be important sources of flavonols (quercetin, myricetin, and kaempferol) and flavones (luteolin and apigenin) were analyzed biochemically. The database contained values from the analyzed foods, previously published values from Dutch foods, and imputed values.
  
  
  METHODS
  Means and standard deviations, contributions of foods to summed intake of each flavonoid, and Pearson correlation coefficients were calculated.
  
  
  RESULTS
  Of the flavonols and flavones studied, quercetin contributed 73% in women and 76% in men. The mean flavonol and flavone intake was approximately 20 to 22 mg per day. Onions, tea, and apples contained the highest amounts of flavonols and flavones. Correlations between the intakes of flavonols and flavones and intakes of beta carotene, vitamin E, vitamin C, folic acid, and dietary fiber did not exceed 0.35.
  
  
  CONCLUSIONS
  Although flavonols and flavones are subgroups of flavonoids hypothesized to be associated with reduced risk of coronary heart disease, data on flavonoid intake has been limited due to the lack of food composition data. Nutrition professionals can use these and other published data to estimate intake of flavonoids in their populations. This work should facilitate the investigation of this class of dietary antioxidants as a contributor to disease prevention.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Sampson
authors.forename: Eric
authors.initials: E
authors.lastname: Rimm
authors.forename: Peter C H
authors.initials: PC
authors.lastname: Hollman
authors.forename: Jeanne H M
authors.initials: JH
authors.lastname: de Vries
authors.forename: Martijn B
authors.initials: MB
authors.lastname: Katan
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D047310:Apigenin; D002908:Chronic Disease; D004034:Diet Surveys; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage*; D044948:Flavonols; D005504:Food Analysis; D005638:Fruit / Q000737:chemistry; D006801:Humans; D044949:Kaempferols; D047311:Luteolin; D008297:Male; D008875:Middle Aged; D019697:Onions / Q000737:chemistry; D011794:Quercetin; D011795:Surveys and Questionnaires; D014481:United States; D014675:Vegetables / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D044948:Flavonols; D044949:Kaempferols; C006552:kaempferol; C040015:myricetin; D047310:Apigenin; D011794:Quercetin; D047311:Luteolin