Green Tea

Green Tea Reduces Risk of Breast Cancer

Recent studies have also identified two mechanisms through which green tea works against breast cancer. Not only does EGCG inhibit the activity of telomerase, an enzyme that plays a key role in cell division, in breast cancer cells, but it also offers help to women with estrogen-negative breast cancer, a form of breast cancer that is very hard to treat successfully.

Estrogen-negative breast cancer cells express high amounts of the epidermal growth factor Her-2/neu, while in the more treatable estrogen-positive form of breast cancer, estrogen-receptor alpha (ERalpha) is expressed. According to a study published in the October 2004 issue of Molecular and Cellular Biology, EGCG induces the expression of ERalpha rather than Her-2/neu in breast cancer cells.

A large studies, including a meta-analysis of 13 studies published July 2006 in Carcinogenesis (Sun CL et al), suggest that green tea reduces risk of breast cancer. In this study, compared to women who did not drink green tea, those consuming the most green tea were 22% less likely to develop breast cancer.

References :

Sun CL, Yuan JM, Koh WP, Yu MC. Green tea, black tea and breast cancer risk: a meta-analysis of epidemiological studies. Carcinogenesis. 2006 Jul;27(7):1310-5. PMID:16855537.

Kaegi E, on behalf of the Task Force on Alternative Therapies of the Canadian Breast Cancer Research Initiative. Unconventional therapies for cancer: 2. Green tea. Canadian Medical Association 1998;158:1033-1035.