Women do not know about one of the biggest health risks linked to drinking too much - a raised chance of breast cancer, says a survey.
While most knew that excessive alcohol intake could lead to liver disease or liver cancer, fewer than one in five linked it to breast cancer.
The YouGov survey of nearly 2,000 men and women was described as "shocking" by health minister Dawn Primarolo.
An estimated four million UK women drink more than recommended levels.
Although many factors might affect our risk of getting breast cancer, limiting how much we drink is one thing we can do to try to reduce that risk
Dr Sarah Cant
Breakthrough Breast Cancer
While there are many different risk factors for developing breast cancer, including family history and obesity, the association between alcohol and breast cancer is well established.
There are more than 45,000 new cases of breast cancer in the UK every year, and the "lifetime risk" of developing it is approximately one in nine.
Women who drink one large glass of wine a day, which means 21 units of alcohol a week compared with the recommended 15, increase this by a fifth.
Drinking two glasses a night boosts it by a third, while three big glasses mean more than a 50% increase.
The survey found that 82% of women were not aware of the connection, compared with 95% who did link it to liver disease, and 71% who were aware it raised the risk of liver cancer.
Public Health Minister Dawn Primarolo said: "It's shocking, even for me, to see the potential risks of drinking over recommended guidelines in black and whilte.
"One large glass of 12% wine takes a woman to her recommended daily limit in just one drink."
The concern is echoed by charity Breakthrough Breast Cancer, whose own research last year found that women were unaware of the underlying causes of breast cancer, falsely believing that most cases were due to family history rather than lifestyle or other factors.
Dr Sarah Cant, from the charity, said: "Although many factors might affect our risk of getting breast cancer, limiting how much we drink is one thing we can do to try to reduce that risk - it's never too late to change your drinking habits."
Don Shenker, chief executive of Alcohol Concern, said: "We know that women are more likely than men to buy their alcohol in supermarkets.
"With wine being the alcoholic drink of choice for most women who do drink, we are seeing many supermarkets responding to this and selling heavily discounted wine, with Tesco offering some bottles for £3 or three bottles for £10.
"Alcohol generally is some 65% more affordable today than in 1980.
"As levels of consumption are found to be related to affordability of alcohol, action is urgently needed to stop supermarkets selling alcohol at such low prices."