Benefits
Today, scientific research provides hard evidence for the health benefits
long associated with green tea. For example, in 1994 the Journal of the National
Cancer Institute published the results of an epidemiological study indicating
that drinking green tea reduced the risk of esophageal cancer in Chinese men
and women by nearly sixty percent. University of Purdue researchers recently
concluded that a compound in green tea inhibits the growth of cancer cells.
There is also research indicating that green tea lowers total cholesterol levels,
as well as improving the ratio of good (HDL) cholesterol to bad (LDL) cholesterol.
Links are being made between the effects of green tea and the "French Paradox." For
years, researchers were puzzled by the fact that, despite consuming a diet
rich in fat, the French have a lower incidence of heart disease than Americans.
The answer was found to lie in red wine, which contains resveratrol, a polyphenol
that limits the negative effects of smoking and a fatty diet. In a 1997 study,
researchers from the University of Kansas determined that EGCG is twice as
powerful as resveratrol, which may explain why the rate of heart disease among
Japanese men is quite low, even though approximately seventy-five percent are
smokers.
Why don't other Chinese teas have similar health-giving properties? Green,
oolong, and black teas all come from the leaves of the Camellia sinensis plant.
What sets green tea apart is the way it is processed. Green tea leaves are
steamed, which prevents the EGCG compound from being oxidized. By contrast,
black and oolong tea leaves are made from fermented leaves, which results in
the EGCG being converted into other compounds that are not nearly as effective
in preventing and fighting various diseases.
New evidence is emerging that green tea can even help dieters. In November
1999, the American Journal of Clinical Nutrition published the results of a
study at the University of Geneva in Switzerland. Researchers found that men
who were given a combination of caffeine and green tea extract burned more
calories than those given only caffeine or a placebo.
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