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Green Tea

Signs and Symptoms for Nutrient Applications

- Antioxidant - Cancer prevention - Adjunct to radiation treatment (may reduce tissue damage) - Cardiovascular support - Stroke prevention - Blood sugar support and obesity

Clinical Applications/Research

Green Tea

Green tea was originally cultivated in ancient China from 2700 BC. The plant was used historically by Buddhists to stay awake during long meditations. It was used by Daoists to promote health and longevity. Traditional Chinese medicine has used green tea for body aches and pains, immune enhancement, headaches, digestion, flatulence, depression, poor eyesight and detoxification. Green tea is said to neutralize poisons, reduce excess fats and clear phlegm. The tannins in green tea have antidiarrhea activity.

Cancer Adjunctive Therapy

The active constituents in green tea are polyphenols, particularly the catechin called epigallocatechin gallate (EGCG). The polyphenols are believed to be responsible for the health-giving properties of green tea. The polyphenols are known to possess strong antioxidant, anticarcinogenic and antibiotic properties (Snow J. Herbal monograph: Camellia sinensi 9L.) Kuntze (Theaceae) protocol. J Botanical Medicine Autumn: 47-51, 1995). The polyphenols found in green tea are said to surpass both vitamin C and E in their antioxidant properties. Studies suggest that 3 cups of green tea daily may provide protection against cancer. Green tea supplements are manufactured for people who do not want to consume large amounts of tea daily. Green tea has been shown to inhibit the mutagenicity and/or chromosomal damage caused by carcinogens in bacterial and mammalian cells. This plant may be useful to prevent some cancers and oxidation-related diseases (Cheng S, et al, Progress in studies on the antimutagenicity and anti-carcinogenicity of green tea epicatechins. Chin Med Sci J 1991 Dec;6(4):233-8; Wang ZY, et al, Antimutagenic activity of green tea polyphenols. Mutat Res 1989 Jul;223(3):273-85). Researchers suggest that the anti-mutagenic, anti-proliferative and anti-neoplastic effects of green tea are anticancer mechanisms that may explain the cancer preventive efficacy in human studies (Steele VE, et al, Comparative chemopreventive mechanisms of green tea, black tea and selected polyphenol extracts measured by in vitro bioassays. Carcinogenesis 2000 Jan;21(1):63-7). Green tea has been shown to induce cell suicide (apoptosis) selectively among cancer cells, but not in normal cells (Isemura M, et al, Tea catechins and related polyphenols as anti-cancer agents. Biofactors 2000;13(1-4):81-5). Green tea out-performed a conventional chemotherapy agent in preventing and / or inhibiting tumor growth in mice transplanted with human non-Hodgkin’s lymphoma cell lines ( Bertolini F, et al, Inhibition of angiogenesis and induction of endothelial and tumor cell apoptosis by green tea in animal models of human high-grade non-Hodgkin's lymphoma. Leukemia 2000 Aug;14(8):1477-82). Prospective cohort studies indicate decreased relative risk of cancer incidence in both sexes for those consuming more than 10 cups a day. Significant delay in cancer onset is linked to increased consumption of green tea (Nakachi K, et al, Preventive effects of drinking green tea on cancer and cardiovascular disease: epidemiological evidence for multiple targeting prevention. Biofactors 2000;13(1-4):49-54).

Cardiovascular Effects

Green tea has also demonstrated positive cardiovascular effects. Epidemiological studies have shown that tea catechin intake is associated with lower risk of cardiovascular disease. Green tea constituents help prevent oxidation of plasma low-density lipoprotein (LDL), a contributing factor in the formation of atherosclerotic plaques and consequent cardiovascular disease. Based on studies with healthy human volunteers, researchers conclude that green tea contributes to the prevention of cardiovascular disease by increasing plasma antioxidant capacity (Nakagawa K, et al, Tea catechin supplementation increases antioxidant capacity and prevents phospholipid hydroperoxidation in plasma of humans. J Agric Food Chem 1999 Oct;47(10):3967-73). Based on human arteriographic evidence, green tea consumption tends to be inversely associated with coronary atherosclerosis in men, but not in women. The protective effect seems to require the consumption of 4 or more cups of green tea daily (Sasazuki S, et al, Relation between green tea consumption and the severity of coronary atherosclerosis among Japanese men and women. Ann Epidemiol 2000 Aug;10(6):401-8).

Suggested Dosage

250-300 mg once or twice daily or as directed by your healthcare professional.

Contraindications/Toxicology

Non-caffeine green tea supplements are suggested to avoid the caffeine side effects which can include restlessness, tremor, and heightened excitability.

Disclaimer: The statements above have not been evaluated by the FDA. The nutritional suggestions and research provided are for informational purposes only and are not intended to diagnose, treat, cure or prevent disease and should not be used as a substitute for sound medical advice. Please see your health care professional in all matters pertaining to your physical health.

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