How Many Alcohol Units a Week are Safe

It can be hard to figure out how many alcohol units you can safely drink per week. It can be hard to figure out how many units of alcohol go into any single serving. Is a beer each evening OK? Is five?

There are lots of different alcoholic drinks. Each brings its own measurements – pints, bottles, glasses, large and small glasses, shots, doubles… It’s a lot. But, how many of these should you be limiting yourself to?

It can be baffling. However, it can be a good idea to get your head around it all, to keep yourself safe and in the best of health.

Alcohol units

We first began counting so called ‘alcohol units’ way back in the late eighties. The idea was introduced as a way to help people keep tabs on how much they were drinking, how often, and so on.

Units themselves are straightforward enough. Each unit is an expression of pure alcohol in any given drink. Simply, one unit is equal to 8 g, or 10 ml, of pure alcohol. This is roughly what an average adult can safely process in one hour. Theoretically, if you drink something with 10 ml of alcohol in it, it should be out of your system about an hour later. This does however depend on the health of your liver and whether it is working under pressure to process a backlog of units.

Different drinks contain different numbers of units. As you may have guessed, stronger drinks will contain more units in them. For example, a pint of strong cider may contain three units, whereas a relatively weak lager may have two.

Figuring out alcohol units in a drink

Alcohol units are simply ways of expressing the standard measurement of alcohol by volume (or ABV for short.) This is a measurement of the amount of pure alcohol within any given total volume of drink, expressed as a percentage.

You will have seen this on cans of beer and bottles of wine and spirits. Wine will generally be between 11-13% ABV. 11-13% is pure alcohol. Beer will typically be more like 4-5%, meaning that it is much weaker than wine. Spirits such as whiskey or vodka will be much stronger, generally at 35% or more.

Unit contents is easy enough for brewers and manufacturers to figure out using ABV. The formula is simple:

• strength (ABV) x volume (ml) ÷ 1,000 = units

Luckily, you don’t have to go through this calculation every time you want a drink! Most bottles and cans will have the number of units contained in them clearly labelled. Using our example above, and rounding up, you will therefore often see weaker lagers’ packaging stating that they are 2.3 units per pint.

How many alcohol units should you limit yourself to?

Please note the title – how many should you limit yourself to? When discussing alcohol units, we aren’t talking about suggested intake. This is all your maximum intake. It is the amount you should not regularly exceed in accordance with the Chief Medical Officers Safe Drinking Guidelines. Realistically, you will want to keep your drinking to a minimum to promote optimal health.

The safe drinking guidelines state that you should consume no more than fourteen units per week, this applies to both men and women.

14 units is about six of our weaker lagers from above. It’s about ten small glasses of wine (though wine is stronger, you obviously don’t drink it in pint glasses, so a small glass itself has relatively few units – about 1.4.)

Furthermore, binge drinking is advised against as it can be dangerous. Binge drinking is where you drink lots of alcohol in one sitting. It is unhealthy to drink 14 units in one day, even if this is the only drinking you do that week. Just because you aren’t exceeding your healthy limit, this case is still bad for you. Your liver becomes less efficient at removing alcohols toxins when it is overloaded.

Ideally, the recommended 14 units should be spread over several days. The safe drinking guidelines suggest aiming for at most three, and never really going over four units daily (two pints of lager or three glasses of wine per day). It is also recommended that you have a few alcohol -free days each week to allow your body to recover.

These numbers are all for regular consumption. Of course, if you have a celebration, you can go over this. Weddings, birthdays, holidays, graduations and so on are licence for us all to occasionally let our hair down a bit. However, if you can stick to these guidelines for most weeks (45 or more per year, say), you should be able to stay healthy.

Why limit alcohol intake?

There are very good reasons for this guidance. Regularly going above fourteen alcohol units a week can have serious ramifications for your health. We are seeing increasing evidence for this.

There is a strong link between regular, excessive alcohol consumption and the development of many illnesses, including liver and renal damage and certain cancers. A decade or two of regular excessive alcohol intake (more than fourteen units of alcohol per week) can significantly increase your likelihood of suffering with:

• Cancer, especially of the throat, mouth, and breast
• Heart disease
• Liver disease
• Stroke
• Brain damage and damage to your nervous system

Alcohol is also highly addictive and damaging to your mental health and wellbeing. It can exacerbate or even cause depression and anxiety. It can lead to low mood and energy levels. Even moderate drinking can greatly impair your cognitive health and function. There is a strong link between excessive drinking and suicide.

It was previously believed that small amounts of alcohol could help to prevent certain illnesses. For example, it was thought that red wine could help to ward off heart disease. However, this link is far weaker than was once assumed, according to the most up-to-date data.

Limiting your alcohol intake can greatly limit these risks, though it can’t negate them entirely. Do note that there is no ‘risk-free’ amount of alcohol intake. Keeping your intake below fourteen units of alcohol per week is low-risk, not necessarily ‘safe’. Going above it is high risk.

How to drink healthily

Drinking alcohol is not physically healthy. However, you can have a healthy relationship with alcohol, providing you do not suffer from an alcohol use disorder. You can enjoy its benefits – the nice taste, the sociability of group drinking, the relaxation and sensation involved – in a healthy setting.

The key is limiting intake and rarely drinking to get drunk.

As above, binge drinking should be a very rare event. If you can, avoid it altogether. Drinking too much at once can leave you very vulnerable. You will be more accident-prone, more likely to misjudge risky situations, and far more likely to lose self-control.

Pace yourself, drinking slowly and alternating alcohol with water or soft drinks. Limit intake. Have food when you are drinking, or at least on a full stomach. Know your limits. If you know that just a couple of drinks will go to your head and expose you to risky behaviour, don’t take that chance.

The Chief Medical Officer’s (CMO’s) drinking guidelines on alcohol units

This is all borne out by the Chief Medical Officer’s official advice. Their offices advise that lower levels of intake are safer. They advise that you keep your drinking below fourteen alcohol units per week.

The CMO also advises that you spread your drinking out, rarely if ever binge drinking. They point to research stating that having one or more heavy drinking episodes per week can increase your risk of long-term sickness and injury.

The CMO advise you keep a few non-drink days per week to allow your body to recover. Furthermore, if you are pregnant or breastfeeding, no amount of alcoholic units are deemed safe.

Your reference guide to alcohol units in common drinks

We’ve run through how to work out the alcohol units in any given drink using a simple equation and the drink’s ABV. You can also find it stated on any alcoholic drink’s packaging. However, as a simple reference, I’ve included below the average units per serving across a range of common alcoholic drinks.

• Single (25 ml) serving or shot of spirits (average ABV 40%) = 1 unit
• Large (35 ml) serving or shot of spirits = 1.4 units
• Alcopop (Smirnoff Ice etc), 275 ml at ABV 5.5% = 1.5 units
• Small glass (125 ml) of wine (average ABV 12%) = 1.5 units
• Standard/regular/medium glass (175 ml) of wine = 2.1 units
• Large glass (250ml) of wine = 3 units
• Bottle (330 ml) of beer (average ABV 5%) = 1.7 units
• Can (440 ml) of beer = 2.4 units

This will hopefully five you an idea of your average alcohol consumption.

If you are regularly exceeding 14 units of alcohol per week and unable to reduce to the safe guidelines, this suggests you may have a problem

Do you need help with alcohol?

Not everyone is able to drink safely and this applies to those with an alcohol use disorder (AUD). Whilst these people are a minority, they process alcohol differently. This leaves them vulnerable to drinking excessively, heavily and frequently.

If you think this may be you, then you are in the right place. Our knowledge hub offers a wealth of information on alcoholism and sources of support. You can also use our platform to connect with meetings and with others who are trying to overcome a problem with alcohol, and those who have solved the problem.

References:

• UK Chief Medical Officers low risk drinking guidelines: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/545937/UK_CMOs__report.pdf
• UK low risk drinking guidelines: https://www.drinkaware.co.uk/facts/alcoholic-drinks-and-units/low-risk-drinking-guidelines
• Alcohol misuse: https://www.nhs.uk/conditions/alcohol-misuse/