Flavonoids not beneficial as antioxidant

CORVALLIS, Ore., March 6 (UPI) -- Flavonoids found in fruits and vegetables have little nutritional importance, but they do protect against heart disease and cancer, says a U.S. study.

An analysis by scientists from the Linus Pauling Institute at Oregon State University in Corvallis say flavonoids had been thought to be nutritionally important for their antioxidant activity, but they actually have little or no value in that role.

The study, published in Free Radical Biology and Medicine, found flavonoids are highly metabolized, which alters their chemical structure and diminishes their ability to function as an antioxidant. Although the compounds appear to have three to five times more antioxidant capacity than vitamins C or E, the body sees them as foreign compounds and modifies them for rapid excretion in the urine and bile. However, this process may also eliminate carcinogens, according to Balz Frei, director of the institute.

Flavonoids are also found in coffee, tea, wine, beer and chocolate.