A survey carried out in Britain has revealed that most people haven't a clue how much alcohol the average glass of wine contains.
The results of a survey conducted for the Department of Health have revealed that three-quarters of drinkers do not know that a typical glass of wine contains three units of alcohol.
The YouGov survey questioned 1,429 drinkers in England and also found that more than a third did not know the recommended daily limit of 2-3 units for women and 3-4 for men.
The survey comes at a time when the governments of Britain and Australia and other countries are concerned about alcohol consumption and the damage alcohol abuse causes in communities.
Both in the UK and Australia campaigns promoting sensible drinking are being launched - so the survey results come at an opportune moment.
Experts believe as glass sizes have increased and some drinks have become stronger people are unaware that they are in fact drinking far more.
The internet survey revealed that while half those questioned drank alcohol at least two or three times a week and 82% said they knew what a unit of alcohol was, 77% did not know how many units were in a typical class of wine.
Experts say people need to have a better understanding of how much they're drinking by adding up their units.
More than half of those polled thought a large glass of wine would contain two units, when it actually contains three and 58% did not know a double gin and tonic contains two units - only 36% of women and 50% of men knew their recommended daily drinking limits.
The Know Your Limits campaign in Britain aims to tell drinkers how many units are now in their drinks and help them stick to their recommended limits; the campaign includes adverts on television, radio and newspapers showing the number of units in individual drinks.
The adverts use ordinary family situations to get over the message of how many units are in typical alcoholic drinks and also warns how too much regular drinking can damage their health.
The campaign aims to reduce binge drinking among the over-25s by reminding social drinkers to stay within recommended limits.
Experts say alcohol can be a major contributing factor in many health disorders so it is important people think about how much alcohol they drink.
Many haemorrhagic stroke deaths every year are associated with alcohol and statistics show that women who drink over double their recommended limits are more than four times likely to suffer a stroke, and men almost twice as likely.
The Department of Health says even those who think they consume alcohol in moderation could be putting their health at risk.