Compared to women who seldom or never drink tea, women who drink two or more cups of tea per day have a 46% lower risk of developing ovarian cancer. These results were published in the Journal of the American Medical Association (JAMA).
Ovarian cancer has the highest mortality rate of all gynecologic cancers. According to the American Cancer Society, it is the fourth leading cause of cancer death among U.S. women; 22,220 new cases and 16,210 deaths are projected for 2005. Since the causes of ovarian cancer are poorly understood, researchers continue to work to identify factors that increase or decrease the probability of developing this disease.
Laboratory studies have suggested that tea polyphenols (antioxidant substances found in tea leaves) may have cancer preventive properties. Few studies in humans, however, have addressed the question of whether tea consumption reduces the risk of ovarian cancer.
To evaluate the relationship between tea consumption and risk of ovarian cancer, researchers in Sweden evaluated 61,057 women between the ages of 40 and 76. Information about tea consumption was collected from a questionnaire that asked about usual intake of 67 foods and beverages. The questionnaire was completed at the time of study enrollment (between 1987 and 1990). Follow-up continued through December 2004.
During the average of 15 years of follow-up, 301 women developed ovarian cancer. Women with a higher level of tea consumption had a reduced risk of developing ovarian cancer.
Compared to the risk of ovarian cancer among women who seldom or never drank tea, risk of ovarian cancer was reduced by 18% among women who drank less than one cup of tea per day; by 24% among women who drank one cup of tea per day; and by 46% among women who drank two or more cups of tea per day.
The researchers conclude that tea consumption may reduce the risk of ovarian cancer. They recommend additional studies to confirm this finding.
Reference: Larsson SC, Wolk A. Tea Consumption and Ovarian Cancer Risk in a Population-Based Cohort. Archives of Internal Medicine. 2005;165:2683-2686.