Bioavailability of the dietary antioxidant flavonol quercetin in man

Cancer Lett. 1997 Mar 19;114(1-2):139-40. doi: 10.1016/s0304-3835(97)04644-2.

Abstract

Quercetin, a dietary antioxidant flavonoid, has anticarcinogenic properties. We quantified the absorption of quercetin in ileostomists. Absorption was 52 +/- 5% for quercetin glucosides from onions, 17 +/- 15% for quercetin rutinoside, and 24 +/- 9% for quercetin aglycone. The plasma quercetin concentration in subjects with an intact colon, after ingestion of fried onions, apples and pure quercetin rutinoside, decreased slowly with elimination half-lives of about 25 h. Thus, repeated dietary intake of quercetin will lead to accumulation in plasma. The relative bioavailability of quercetin from apples and rutinoside was one-third of that from onions. Absorption kinetics and bioavailibility might be determined by the type of glycoside. Dietary quercetin could increase the antioxidant capacity of blood plasma.

Publication types

  • Clinical Trial

MeSH terms

  • Allium / metabolism
  • Anticarcinogenic Agents / blood*
  • Antioxidants / metabolism*
  • Biological Availability
  • Fruit / metabolism
  • Humans
  • Quercetin / blood*
  • Time Factors

Substances

  • Anticarcinogenic Agents
  • Antioxidants
  • Quercetin