Swedish researchers have found tantalizing but far from conclusive evidence that drinking a couple of cups of tea every day might help reduce the risk of developing ovarian cancer.
The study involved 61,057 Swedish women who answered a questionnaire about their diets and then were tracked for an average of 15 years through 2004. During that time, 301 women developed ovarian cancer. Those who reported drinking two or more cups of tea a day were 46 percent less likely to develop the disease than women who drank no tea. Drinking fewer than two cups also appeared to help, but not as much.
The researchers did not break out the results by tea types, but most of the tea drinkers consumed black tea. Both black tea and green tea contain polyphenolssubstances thought to block cell damage that can lead to cancer.
Previous studies on whether tea might help prevent various kinds of cancer have yielded conflicting results. Researchers Susanna Larsson and Alicja Wolk of the Karolinska Institute in Stockholm said more research is needed to sort out the inconsistencies. Their study was published in Monday's Archives of Internal Medicine. "If these findings are real, they'd be important because ovarian cancer is the fourth leading cause of cancer death in women," said Marji McCullough, a nutritional epidemiologist at the American Cancer Society.
Julie Buring of Harvard's Brigham and Women's Hospital, who studies chronic diseases and cancer, said that factors other than tea drinking might explain the results and that the tea drinkers may have been healthier than the other women.
"Certainly the idea of exploring agents or lifestyles that could make a difference on ovarian cancer would be very timely and important," Buring said. "My concern is with these kinds of studies, that people who drink two cups of tea daily are different from people who don't in ways that go through their whole lifestyle."
Ovarian cancer is diagnosed in more than 20,000 U.S. women yearly. On average, U.S. women face about a 1-in-58 chance of developing the disease. It is hard to detect early because its symptoms, including abdominal bloating, indigestion, and urinary urgency, can be vague and mimic less serious conditions.