Tea consumption may reduce ovarian cancer risk
December 13, 2005
by Keith Nunes
CHICAGO — Women who drank at least two cups of tea a day had a lower risk of ovarian cancer than those who did not drink tea, according to a study in the December issue of Archives of Internal Medicine.
Evidence from laboratory studies indicates green and black tea preparations may protect against various cancers. But few epidemiological studies have examined the relationship specifically between tea consumption and the risk of ovarian cancer, according to background information in the article.
Susanna C. Larsson and Alicja Wolk, of the National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden, examined the association between tea consumption and the risk of ovarian cancer in 61,057 women, aged 40 to 76, who were participants in the population-based Swedish Mammography Cohort. Participants completed a validated 67-item food frequency questionnaire at enrollment between 1987 and 1990, and were followed for cancer incidence through December 2004.
At baseline, 68% of the participants reported drinking tea (mainly black tea) at least once per month. During an average follow-up of 15.1 years, 301 women were diagnosed as having invasive epithelial ovarian cancer.
"We observed a 46% lower risk of ovarian cancer in women who drank two or more cups of tea per day compared with non-drinkers," the authors reported. "Each additional cup of tea per day was associated with an 18% lower risk of ovarian cancer."
Women who drank less than one cup of tea per day had an 18% lower risk of ovarian cancer than non-drinkers. The risk was 24% lower for women who drank one cup of tea per day.
"This association does not depend on lower coffee consumption among women with high tea consumption; coffee is not associated with ovarian cancer risk in this cohort," the authors wrote.
"In summary, our results from a large population-based cohort of Swedish women suggest tea consumption may lower the risk of ovarian cancer," the authors concluded. "Because prospective data on this relationship are scarce, our findings need confirmation by future studies."