Drinking a couple of cups of tea a day may help reduce the risk of developing ovarian cancer, say Swedish researchers who caution more research is needed to confirm the findings.

The study followed the health of 61,057 women between the ages of 40 and 76. Participants completed questionnaires about their diet from 1987 until 2004.

During the study, 301 women were diagnosed with invasive epithelial ovarian cancer.

Tea contains substances thought to block cell damage that can lead to cancer.

"We observed a 46 per cent lower risk of ovarian cancer in women who drank two or more cups of tea per day compared with non-drinkers," said the study's authors, Susanna Larsson and Alicja Wolk of the Karolinska Institute in Stockholm.

"Each additional cup of tea per day was associated with an 18 per cent lower risk of ovarian cancer,'" they wrote in the Dec. 12 issue of Archives of Internal Medicine.

When the study began, two-thirds of the participants reported drinking tea, mainly black tea, at least once per month.

Healthier diet for tea drinkers

Research in test tubes and animals suggests antioxidants in the drink can help stop the mutations that lead to cancer.

Another study that followed fewer women to look for a relationship between tea consumption and ovarian cancer risk found no clear evidence of a link.

Case-control studies, a less rigorous study design that looks at diets at the time of diagnosis, have also showed inconsistent results.

In the latest study, Larsson and Wolk note women who drank more tea seemed to be more health conscious, eating more fruits and vegetables, and they were generally leaner, which is an alternative explanation for the findings.

The association did not seem to depend on lower coffee consumption, and coffee was not associated with ovarian cancer in this group, the researchers reported.

"Because prospective data on this relationship are scarce, our findings need confirmation by future studies," they wrote.

In 2005, there were an estimated 2,400 new cases of ovarian cancer in Canada, and an estimated 1,550 deaths, according to Canadian Cancer Statistics 2005 report.