A cancer specialist said evidence that just one drink a day can increase the risk of breast cancer by 7% was not promoted widely enough among women.
He said there was now "seriously strong" data showing a link between alcohol - even at low consumption levels - and the disease.
Alcohol problems are worse in Greater Glasgow and Clyde than in the rest of Scotland, the UK or Western Europe.
Around 1800 new cases of breast cancer are diagnosed every year in the west of Scotland.
Professor Peter Boyle, of Strathclyde University's Institute of Global Public Health, said more research was urgently needed into the risks of drinking for women who already have a family risk of the disease.
Asked if those women should be advised not to drink alcohol at all, he said: "It's a question to which no one knows the answer. There is no information available. It is one of the major research gaps."
It is estimated there are 13,650 problem alcohol users in Glasgow city area alone.
More than 57% of women in Scotland exceed the recommended maximum daily amount at some point in the week.
Professor Boyle said: "We have got to be a lot better informed about the link between alcohol consumption and breast cancer. There is now seriously strong data indicating that even moderate alcohol consumption increases the risk of breast cancer."