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Quest Vitamins LTD,
8 Venture Way,
Aston Science Park,
B7 4AP.

Tel: 0121 359 0056
Fax: 0121 359 0313
Registered in England No. 2530437

Green Tea (Camellia sinensis)


Green and black tea are derived from the same plant. However, the method of production varies. The tea plant is an evergreen shrub or tree which originated in southern Yunnan and the Assam province of India. Camellia sinensis is now widely cultivated primarily in China, Japan, North Africa and the Middle East. The black tea that we are more familiar with as a morning or afternoon beverage has been allowed to oxidise, whereas green tea is produced by lightly steaming, then drying the fresh-cut leaf, this process keeps the polyphenols (a group of active compounds) intact.

The herb green tea contains many useful compounds, several of which have an identified role in the body. Others await further investigation.


According to traditional medicine, green tea possesses stimulant, digestive, diuretic and antitoxic properties.


Part of the herb used: Leaves
Leaf extract 100-300mg daily


Green tea has been found to protect against Atherosclerosis, is antihepatotoxic and a powerful antioxidant.

Green tea polyphenols enhance antioxidant defence systems and the activity of certain antioxidant enzymes. Studies have shown that green tea polyphenols are better scavengers of free radicals than vitamins C and E. (1) Green tea is particularly effective at protecting against free radical damage in the gastrointestinal tract.

Numerous studies have shown that green tea extract offers protection against tumour development, by inhibiting harmful carcinogens and nitrosamines which are mutagens. (2)

Green tea has proven effective in protecting the skin against UV damage. (3)

Heart disease
Green tea has been found to decrease total serum cholesterol levels without altering HDL cholesterol (4) and it may protect against cardiovascular disease. (5)

Green tea has anti-inflammatory properties. (6,7)


Green tea is safe from side effects.

Green tea products containing caffeine may produce a stimulant effect (Anxiety, Insomnia, irritability etc.) Caffeine-free extracts are available.

Pregnant and lactating women should consult with a qualified health professional before taking green tea, due to a lack of safety data at this time.

Green tea is not recommended for use by children.


There are no interactions or contra-indications listed for green tea.


Green Tea for Ovarian Health

The polyphenol epigallocatechin-3-gallate (EGCG), the principal mediator of the green tea, has been known to possess antitumor effect.

In this study, they examined the green tea and EGCG effects on two ovarian carcinoma cell lines. EGCG inhibited ovarian cancer cell growth and induced apoptosis. Treatment with green tea or EGCG reduced the induced cell proliferation and invasion. Tumor growth was significantly inhibited by oral administration of green tea. These results provide a novel insight into the mechanism by which EGCG, may inhibit ovarian carcinoma growth, suggesting that EGCG may be useful in preventing and treating ovarian carcinoma.

Mol Cancer Ther 2006;5(6):1483-92


1. Cell Biophysics, 1989, 14:175-185.
2. Prev Med, 1992, 21;377.
3. Carcinogenesis, 1992, 13;6:947-954.
4. Prev Med, 1992, 21:526.
5. BMJ, 1995, 310:693-696.
6. Cell Biophys. 1989, 14:175.
7. Carcinogenesis, 1992, 13:947.