Archaeological evidence suggests that tea leaves steeped in boiling
water were consumed as many as 500,000 years ago. Botanical evidence
indicates that India and China were among the first countries to
cultivate tea
Green tea contains polyphenols which protect against certain cancers,
and are also potent antioxidants. These antioxidants have been shown to
be highly beneficial to the heart by helping prevent the oxidation of
LDL cholesterol.
There are four primary polyphenols in green tea, often collectively
referred to as catechins. They are powerful antioxidants, and have been
shown in recent studies to fight viruses, slow aging, and have a
beneficial effect on health.
Much of the initial evidence that green tea is anti-carcinogenic is
based on epidemiological studies which show lower rates of many types
of cancer among populations such as Japan and China that drink green
tea as part of a daily cultural habit.
Clinical tests have demonstrated that the catechins in green tea
destroy free radicals which are highly reactive molecules and fragments
of molecules that can damage the body at the cellular level leaving it
susceptible to cancer, heart disease, and many other degenerative
diseases More recently, controlled studies on green tea extract have
yielded impressive results, identifying the polyphenol
(-)-epigallocatechin gallate (EGCG) as the responsible component. EGCG
is able to force certain cancer cells into a situation in which they
must die or be killed in a process called ''apoptosis''. Further
evidence shows that EGCG has an inhibitory effect on the enzyme,
urokinase, which is required for tumor formation, thus preventing the
formation of tumors.
It has been shown that (EGCG), an antioxidant found in green tea, is at
least 100 more times more effective than vitamin C and 25 times more
effective than vitamin E at protecting cells and DNA from damage
believed to be linked to cancer, heart disease and other serious
illnesses. This antioxidant has twice the benefits of resveratrol,
found in red wine.
The only possible negative side effect from green tea is possible
insomnia because it contains some caffeine. Its caffeine content is,
however, much lower than coffee.
About the Author
Ian Finlayson is webmaster of The Herb Spiral, a site committed to presenting no-hype information on medicinal herbs. More information on green tea can be found here
