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"Strongest" Antioxidant Found
in Tea
Friday September 12
By E.J. Mundell
NEW YORK (Reuters) -- Anyone for a steaming hot cup of antioxidants?
One expert says tea leaves contain the strongest known form of the
disease-fighting compounds.
"Our research shows that green tea contains a powerful
antioxidant, known as epigallocatechin gallate, or EGCG," said Dr.
Lester Mitscher, distinguished professor of medicinal chemistry at the
University of Kansas in Lawrence, Kansas. EGCG is the "strongest of
all" the antioxidants he's aware of -- more than 100 times as
effective at soaking up free radicals than vitamin C, and 25 times more
powerful than vitamin E.
Antioxidants are thought to help prevent the development of certain
diseases, especially cancers. They may do this by 'mopping-up' free
radicals -- byproducts of the body's metabolic processes. Left alone, free
radicals can cause damage to cellular DNA, which may in turn trigger
disease.
Mitscher put various teas -- green, black, and oolong -- through tests
designed to spot the presence of antioxidants. Green teas have, by far,
the highest concentrations of active EGCG, Mitscher said. "Green tea
is plucked at the appropriate time and then is immediately steamed,"
he explained. "That heat process prevents the internal oxidation of
these compounds."
He said oolong and black tea leaves are allowed to oxidize during
processing. This oxidization greatly reduces the amount of active EGCG in
those teas. Black tea, for example contains just 40% of the EGCG of green
tea.
The daily tea consumption needed for optimum antioxidant effects has
"not really been firmly established," Mitscher said. But he
points out that in countries like China and Japan, "people
customarily drink 4 or more cups (of green tea) per day." Studies in
those populations reveal "a lower incidence of ...degenerative
diseases," he said. "That's probably a healthy dose. We don't
know that one cup (per day) wouldn't work, but that's really not been
established."
Mitscher presented his findings this week at the American Chemical
Society national meeting in Las Vegas. His study was funded by a grant
from Pharmanex, a company which produces plant-based health care products.

 Copyright © 1998 Tealand.
All rights reserved.
Revised:
May 11, 2008.
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