herb research - green tea

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Name: Green Tea Biological Name: Camellia sinensis Other Names: Green Tea

Parts Used: ActiveCompounds: Green tea contains volatile oils, vitamins,

minerals, and caffeine, but the active constituents are polyphenols,

particularly the catechin called epigallocatechin gallate (EGCG). The

polyphenols are believed to be responsible for most of green tea's roles in

promoting good health.

Research demonstrates that green tea guards against cardiovascular disease

in many ways. Green tea lowers total cholesterol levels and improves the

cholesterol profile (the ratio of LDL cholesterol to HDL cholesterol),

reduces platelet aggregation, and lowers blood pressure. The polyphenols in

green tea have also been shown to lessen the risk of several types of

cancers, stimulate the production of several immune system cells, and have

antibacterial properties-even against the bacteria that cause dental

plaque. History: According to Chinese legend, tea was discovered

accidentally by an emperor 4,000 years ago. Since then, traditional Chinese

medicine has recommended green tea for headaches, body aches and pains,

digestion, depression, immune enhancement, detoxification, as an energizer,

and to prolong life. Modern research has confirmed many of these health

benefits. Remedies For: Green tea is useful for:

Cancer risk reduction

Gingivitis (periodontal disease)

High cholesterol

Hypertension (high blood pressure)

Hypertriglyceridemia (high triglycerides)

Immune function

Infection

 

Most of the studies of the effect of the green tea have been focussed on

its cancer-causing and cancer-protecting aspects. Green tea polyphenols are

potent antioxidant compounds. They are more potent antioxidants than

vitamin E and vitamin C.

Green tea may also increase the activity of the antioxidant enzyme. A

number of animal studies have shown that green tea polyphenols may offer

significant protection from cancer. It is believed that they do so by

blocking the formation of cancer-causing compounds such as nitrosamines,

suppressing the activation of carcinogens, and detoxifying or trapping

cancer causing agents. Green tea is believed to have the greatest effect on

cancers of the gastrointestinal tract such as stomach, small intestine,

pancreas, and colon; lung cancer; and estrogen related cancers including

most breast cancers.

It is interesting to note that green tea prevents cancer, whereas black tea

increases the risk of certain cancers such as cancer of the rectum,

gallbladder, and endometrium. Description: All teas (green.black,and

oolong) are derived from the same tea plant, Camellia sinensis. The

difference is in how the plucked leaves are prepared.

The tea plant has long been cultivated in China. It is an evergreen shrub

or tree that can grow to a height of 30 feet, but is usually maintained at

a height of 2 to 3 feet by regular pruning. The hairy leaves of the tea

plant are used both as a social and medicinal beverage. The parts used ate

the leaf bud and the two adjacent young leaves together with the stem,

broken between the second and the third leaf. Older leaves are considered

inferior in quality.

Green tea, unlike black and oolong tea, is not fermented, so the active

constituents remain unaltered in the herb. It is produced by lightly

steaming the fresh cut leaf. Green tea is very high in polyphenols with

potent antioxidant and anticancer properties. Dosage: Much of the research

documenting the health benefits of green tea is based on the amount of

green tea typically drunk in Asian countries-about three cups per day

(providing 240-320 mg of polyphenols). To brew green tea, 1 teaspoon of

green tea leaves are combined with 250 ml (1 cup) of boiling water and

steeped for three minutes. Tablets and capsules containing standardized

extracts of polyphenols, particularly EGCG, are available; some are

decaffeinated and provide up to 97% polyphenol content-which is equivalent

to drinking four cups of tea. Safety: Green tea is extremely safe. The most

common adverse effect reported from consuming large amounts of green tea is

insomnia, anxiety, and other symptoms caused by the caffeine content in the

herb.