'This study crystallizes many strands of evidence from different studies on different types of cancer and alcohol consumption,' added Jack Siematycki, professor of Canada Research Chair and Guzzo Chair in Environment and Cancer at Montreal University.

The researchers used data originally collected for a large occupational cancer study conducted in Montreal in the 1980s.

The information was a treasure-trove, said Benedetti.

'Lifetime interviews were conducted with people about their job histories, and detailed information about all the things they could have been exposed to was collected,' she said.

'The data also included information about non-occupational factors such as drinking alcohol, smoking cigarettes, diet and socio-economic status, among others.'

She said light drinkers were less affected or not affected at all.

'It is people who drink every day or multiple times a day who are at risk. This adds to the growing body of evidence that heavy drinking is extremely unhealthy in so many ways. Cancer very much included,' the Canadian said.

The study has been published in the current issue of the journal Cancer Detection and Prevention.