Drinking at least two cups of coffee a day can help inhibit the growth of tumours and reduce the risk of recurrence in breast cancer, a new study has claimed.

The study was carried out at Lund University and Skane University Hospital, in collaboration with researchers in the UK.

The study 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 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," researchers said.

The study also found that those who drank at least two cups of coffee a day had smaller tumours and a lower proportion of hormone-dependent tumours.

In the cell study, the researchers looked more closely at two substances that usually occur in the coffee drunk in Sweden - 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, researchers found.

"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," they said.