Many people are confused about sensible drinking levels, researchers have said.
The survey found prices influenced buying more than label information
A poll of more than 250 Edinburgh shoppers found most did not use alcohol labels to help monitor their drinking.
The survey, published in the British Medical Journal, revealed that the vast majority of people were also unaware of the recommended daily alcohol intake.
The Queen Margaret University College study said attempts to explain drinking levels may fail because of confusion about the guidelines.
The researchers asked shoppers about their knowledge of sensible drinking messages and awareness of alcohol labelling.
The Department of Health has advised that men should drink no more than three to four units of alcohol per day and that women should drink no more than two to three units.
A 175ml glass of red or white wine contains about two units, while a pint of ordinary strength lager also has two units.
The survey found most of those questioned were able roughly to define a unit of alcohol.
Only 14% of women and 16% of men were unable to give a response.
But there was poor knowledge of the recommended daily guidance and the poll found that price offers influenced buying more than label information.
Only 8% were aware that women were limited to two to three units and 5% knew men were limited to three to four units a day.
A quarter of women and 19% of men said they used the unit system to monitor their own personal drinking.
Researchers Jan Gill and Fiona O'May said: "This pilot study highlights considerable confusion about sensible drinking messages in the UK.
"Few respondents used the unit system to monitor their drinking."
Jack Law, chief executive of Alcohol Focus Scotland, said the research was further evidence that the sensible drinking message was not getting across to the public.
"People need to have much clearer information about how much is too much, and understand how to use this information to keep their own drinking at safe and healthy levels," he said.
"It is now more difficult for people to accurately monitor their consumption because of larger measures and the fact that many beers and wines are much stronger than they used to be.
"The more responsible drinking information which is accessible to people, including from the point of sale in pubs and shops, the better."