One new epidemiological study indicates consuming green tea may be linked to a dose dependent reduction of ovarian cancer risk.
Results from past laboratory studies indicate that green and black tea may protect against various cancers. However, few epidemiologic studies have explored the relationship between tea consumption and ovarian cancer risk.
In the recent epidemiological study, published in the December 2005 Archives of Internal Medicine, researchers investigated the association between tea consumption and risk of ovarian cancer in 61,057 women aged 40 to 76 years who were participants in the Swedish Mammography Cohort. Participants completed a validated 67-item food frequency questionnaire at enrollment between 1987 and 1990. Researchers followed the subjects through December 2004 to determine cancer incidence.
During an average follow-up of 15.1 years, 301 incident cases of invasive epithelial ovarian cancer developed. After controlling for potential confounders, the study authors determined that the higher the consumption of either green or black tea, the lower the risk of ovarian cancer. Compared with women who never consumed tea or consumed it less than monthly, women who drank less than one cup per day reduced their risk by 18 percent and those drinking one cup per day showed a 24 percent reduced risk. Subjects who drank two or more cups per day had a nearly 50 percent reduction in risk. Each additional cup of tea per day was associated with an 18 percent lower risk of ovarian cancer.
The researchers concluded, “These results suggest that tea consumption is associated with a reduced risk of epithelial ovarian cancer in a dose-response manner.”
Larsson SC, Wolk A. Tea consumption and ovarian cancer risk in a population-based cohort. Arch Intern Med. 2005 Dec 12-26;165(22):2683-6.