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Alcohol units | Guide to units & measures

Introduction

Our easy-to-understand guide gives you the facts and advice on alcohol units and measures.

All drinks are not created equal
So how strong is your drink?
Large or small?
Strategies for lower alcohol drinking

All drinks are not created equal

Discovering how much you are drinking sounds easy doesn’t it? After all, you can drink a pint or a half pint of beer or cider, a single or a double measure of spirits or a glass of wine. And if you’re counting your units it’s easy – two units for a pint, and one unit for half a pint or a spirit and mixer…well, not quite. Unfortunately, the truth is more complicated than that.

How drunk you get depends on how much pure alcohol your drink contains. One way to calculate this is by counting units. The government advises that people should not regularly drink more than the daily unit guidelines of 3-4 units of alcohol for men (equivalent to a pint and a half of 4% beer) and 2-3 units of alcohol for women (equivalent to a 175 ml glass of wine). ‘Regularly’ means drinking every day or most days of the week.

One unit is 10 ml of pure alcohol - the amount of alcohol the average adult can process within an hour. This means that if the average adult drinks a drink with one unit of alcohol in it, within an hour there should in theory be no alcohol left in their bloodstream, (1),but that length of time could differ depending on a person’s body size. (1)

The alcohol content in drinks is also expressed as a percentage of the whole drink. If you take a look at the label of a bottle of wine or a can of lager you will see either a percentage, followed by the abbreviation “ABV” which stands for alcohol by volume, or sometimes just the word “vol”. So, wine that says “13 ABV” on its label contains 13% pure alcohol.

So how strong is your drink?

But the alcoholic content in the same types of drinks can vary a lot. Our tastes in alcohol have also changed. Warm, flat ale may have been our national drink 30 years ago, but imported lagers have gradually become more and more popular, and their alcohol strength can be quite a bit higher than ale. For example, some ales have an alcohol content of 3.5%. But stronger continental lagers can be 5% ABV, or even 6%.

This means that just one pint of strong lager can equate to more than three units of alcohol – almost the daily unit guideline limit if you are a man. And research shows that we are drinking stronger drinks than ever before.

We also drink more wine than we used to, particularly 'new world' wines from hot countries, including Australia, South America and South Africa which can be over 14% ABV compared to the 13% ABV average of European wines.

Mintel, the market researchers, have found that the amount of pure 100% alcohol consumed by British drinkers has increased by 10% since 2000, despite the actual volume of alcohol consumed (in litres) remaining static throughout this period. (2).

“It may be that the majority of consumers are not aware of ABV and don't even notice. So despite a greater societal concern with being healthy … by stealth we are drinking more pure alcohol than ever,” says Jonny Forsyth, a senior drinks analyst at Mintel.

Large or small?

And don’t forget about size either.

Although spirits used to be commonly served in 25ml measures, which are one unit of alcohol, many pubs and bars now serve them in 35ml or 50ml measures.

And if you ask for a glass of wine in a bar you’ll be asked if you want a large or a small glass. You may opt for a large glass thinking you’re getting a bargain, but a large measure is 250ml - which is one third of a bottle. This can be nearly three units of alcohol or more in just one glass. So if you have just two or three drinks, you could easily consume a whole bottle of wine - and almost three times the daily unit guidelines – without even realising.

The good news is that as part of an addition to the Licensing Act 2003, the government in October 2010 made it compulsory for all pubs, bars, clubs and restaurants with an alcohol license to have small measures of beers, ciders, spirits and wine readily available to customers who wish to order them.

Strategies for lower alcohol drinking

At home

If you’re pouring your own drinks at home, it’s easy to drink more than you would usually. Here are some tips to help you keep track of your intake.
Measure spirits instead of free pouring them. The Drinkaware unit measure cup (pictured above) is an ideal way to measure not only spirits, but wine and beer too.
If you drink wine at home, pour small amounts into your glass. If you fill glasses to the rim, you’ll be drinking more than you realise.
Try and pour your own drinks. If your half-full glass is constantly topped up, it’s hard to keep track of how much you are drinking.

Out and about

Use the smartphone version of our MyDrinkaware drink tracking tool. It's free and simple to use.
Ask for a small glass of wine – as well as serving wine in smaller 175ml glasses, some bars serve 125ml glasses of wine – that can be one and a half units of alcohol.
Drink spritzers if you like wine, or pints of shandy if you are a lager drinker. You will get a large drink, but one that contains less alcohol.
Opt for half pints if you prefer higher strength lager or try lower strength beer you - really won’t notice the difference.
Alternate alcoholic drinks with soft drinks
Ask questions. If you are still uncertain about how much you are drinking, ask the bar staff. Do they pour doubles or singles? How big is their large glass of wine?