Several studies have shown that women who drink green tea daily have a reduced risk of developing ovarian cancer.
Australian researchers conducted a green tea ovarian cancer case-control study and a cohort study in China during 1999-2000.
*The case-control study compared 254 women with ovarian cancer with 652 controls. Women who drank green tea daily showed 61% reduced risk of ovarian cancer and women who had been drinking green tea every day for over 30 years showed 77% reduced risk of ovarian cancer (Zhang M, Tea consumption and ovarian cancer risk: a case-control study in China, Cancer Epidemiology, Biomarkers, & Prevention, August 2002).
The cohort study followed the same women for the next three years. Survival was significantly higher for the tea drinkers: 77.9% of the women who drank tea survived three years, while only 47.9% of the non-tea drinkers survived (Zhang M, Green tea consumption enhances survival of epithelial ovarian cancer, International Journal of Cancer, November 2004).
A recent study in the United States examined the risk of ovarian cancer and caffeinated beverages.
781 women from Washington state were compared to 1263 controls. Researchers found no associations between ovarian cancer risk and coffee, decaffeinated coffee, colas, herbal tea, or black tea.
However, there was a significant reduction in ovarian cancer risk of 54% among women who drank at least one cup of green tea daily.
This green tea ovarian cancer risk reduction was the same for both invasive and borderline ovarian cancer cases. It was the same even when Asian women were excluded from the analysis (Song YJ, Coffee, tea, colas, and risk of epithelial ovarian cancer, Cancer Epidemiology, Biomarkers & Prevention. March 2008).
Green tea ovarian cancer studies explain green tea protection
A study using two ovarian cancer cell lines found that EGCG from green tea inhibited the endothelin A receptor (ET(A)R)/endothelin-I (ET-1) axis which is overexpressed in ovarian cancer. EGCG also reduced angiogenesis, vascular endothelial growth factor, and tumor proteinase activation. Through these activities, tumor growth was significantly inhibited (Spinella F, Green tea polyphenol epigallocatechin-3-gallate inhibits the endothelin axis and downstream signaling pathways in ovarian carcinoma. Molecular Cancer Therapeutics, June 2006). Another green tea ovarian cancer study by Spinella with the same two ovarian cancer cell lines found that EGCG significantly reduced the COX-1/2-derived prostaglandin E2 (PGE2) production (Spinella F, Antitumor effect of green tea polyphenol epigallocatechin-3-gallate in ovarian carcinoma cells: evidence for the endothelin-1 as a potential target, Experimental Biology and Medicine, June 2006).
One study examined separate green tea polyphenols including EGCG (epigallocatechin gallate), EGC (epigallocatechin), ECG (epicatechin gallate), and EC (epicatechin) using two lines of ovarian cancer cells. EGCG inhibited all cell lines by 50% while EC only inhibited one cell line by 50%. However, ECG from green tea was more effective than EGCG from green tea at lower concentrations (Ravindranath MH, Epicatechins Purified from Green Tea (Camellia sinensis) Differentially Suppress Growth of Gender-Dependent Human Cancer Cell Lines, Evidence-based Complementary and Alternative Medicine, June 2006).
Korean researchers found that EGCG, the primary antioxidant polyphenol from green tea significantly suppressed ovarian cancer growth in three cell lines in a dose-dependent manner. In other words, the more EGCG, the more cancer reduction. This green tea ovarian cancer study showed that EGCG arrested the cancer cell cycle, modified gene and protein expression to reduce cancer growth, and increased apoptosis or cancer cell death (Huh SW, Anticancer effects of (-)-epigallocatechin-3-gallate on ovarian carcinoma cell lines, Gynecologic Oncology, September 2004).
An antioxidant study using one ovarian cancer cell line, found that while EGCG was effective at suppressing ovarian cancer, selenium had a greater antioxidant effect (Wilson-Simpson F, Physiological responses of ES-2 ovarian cell line following administration of epigallocatechin-3-gallate (EGCG), thymoquinone (TQ), and selenium (SE), Biomedical Sciences Instrumentation, 2007).
Learn more to live longer
The rate of ovarian cancer in the United States has held almost steady for over 30 years. In 2008, the American Cancer Society estimates 21,650 new cases of ovarian cancer and 15,520 women dying from ovarian cancer.
While early detection at early stage cancer improves women's survival rate up to 95%, at least 75% of women are not diagnosed with ovarian cancer until later states (CDC). Please check with your doctor for your personal risk level and appropriate diagnostic tests.
Depending on your health condition, you may want to consider developing the healthy habit of daily green tea.
Knowledge is one of our greatest weapons against disease.
