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Green Tea

Camellia sinsensis, the common tea plant, has been drunk as an infusion throughout Asia since at least 3000 B.C. and remains the most widely consumed hot beverage on the planet. The only difference between green tea and black tea is that, to make green tea, leaves are steamed while to make black tea there is a fermentation process involved. This difference in processing yields a different concentration in the main active ingredient of tea, polyphenols/catechins.

Efficacy

Preclinical data in vitro and in vivo suggest that green tea interferes with carcinogenesis and metastasis along several tumor promotion pathways. The literature describes in-vitro and animal in-vivo data that shows synergistic action of green tea with chemotherapeutic antineoplastic agents such doxorubicin (adriamycin) and tamoxifen.

Clinical data suggest antineoplastic effects of green tea on malignant tissue combined with a protective and reparative effect on cardiac, renal and myeloplastic cells. There is currently no data about optimal concentration and length of administration of green tea extracts in people with active malignancies.

Large epidemiological studies seem to suggest that green tea may play a role in cancer prevention and decreased risk of recurrence.

Safety

Studies have shown green tea is safe for human consumption of up to 800 mg (equivalent to 16 cups of tea a day)

Recommendations

Green tea is a safe beverage to drink during active chemotherapy and radiation but should not be taken in higher doses as a medicine until after completion of primary treatment. Green tea is used as an adjuvant therapy in capsule form to prevent recurrence.

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References - Hide References

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