London, April 22 (IANS): Drinking just two cups of coffee a day can help inhibit the growth of tumours and reduce the risk of recurrence in women who have been diagnosed with breast cancer, a new research suggests.

The researchers combined information about the patients' lifestyle and clinical data from 1,090 breast cancer patients with studies on breast cancer cells.

"The study shows that among the over 500 women treated with (the drug) tamoxifen, those who had drunk at least two cups of coffee a day had only half the risk of recurrence of those who drank less coffee or none at all," explained Ann Rosendahl, one of the researchers from Lund University in Sweden.

"The study also shows that those who drank at least two cups of coffee a day had smaller tumours and a lower proportion of hormone-dependent tumours. We saw that this was already the case at the time of diagnosis," Rosendahl noted.

In the cell study, the researchers looked more closely at two substances found in coffee -- caffeine and caffeic acid.

"The breast cancer cells reacted to these substances, especially caffeine, with reduced cell division and increased cell death, especially in combination with tamoxifen," Rosendahl noted.

"This shows that these substances have an effect on the breast cancer cells and turn off signalling pathways that the cancer cells require to grow," Rosendahl said.

The study appeared in the journal Clinical Cancer Research.