Alcohol and Maintaining Your Weight

The guidance is specific and it is worth knowing rather than estimating.

To keep health risks from alcohol to a low level if you drink most weeks, men and women are advised not to drink more than 14 units a week on a regular basis, to spread drinking over 3 or more days if they regularly drink as much as 14 units a week, and to have several drink-free days each week if they want to cut down.¹

Fourteen units is equivalent to 6 pints of average-strength beer or 10 small glasses of lower-strength wine.¹

One unit equals 10 ml or 8 g of pure alcohol, which is around the amount of alcohol the average adult can process in an hour.¹ The number of units in a drink is based on the size of the drink and its alcohol strength, so a pint of strong lager contains 3 units while the same volume of lower-strength lager has just over 2.¹ A 750 ml bottle of red, white or rosé wine at 13.5% ABV contains 10 units.¹

You can work out any drink yourself: strength (ABV) multiplied by volume in millilitres, divided by 1,000, gives units.¹ A pint of strong lager at 5.2% works out as 5.2 times 568 divided by 1,000, which is 2.95 units.¹ The ABV is on the label of cans and bottles, sometimes written as "vol" or "alcohol volume", or you can ask bar staff.¹

Alcohol contributes energy, and the NHS principle applies as it does to anything else: to stay at around the same weight, the calories your body uses should be the same as the amount you eat and drink, and you are likely to put on weight if you eat and drink more than you use.³

But three indirect effects matter more in practice, and they are the ones people do not account for.

What you eat afterwards. The meal or the snack that follows a few drinks is usually larger and different in composition from what would otherwise have happened. That is often the bigger part of the arithmetic.

Sleep. The NHS notes that longer-term sleep problems can affect your mood, appetite, relationships and social life, and that getting enough sleep supports mood, energy, immune system and overall health.⁸ Alcohol disrupts sleep quality even when it shortens the time taken to fall asleep, and a poor night reliably makes the following day harder to manage.

The next day's activity. Whatever activity was planned for the following morning is the first casualty. Given that NICE's maintenance activity figure is 60 to 90 minutes a day for people who have lost weight, losing a day matters more than it once did.⁷

Considering treatment for weight management? You can start an assessment with a Cloud Pharmacy clinician, who will review your medical history and confirm whether treatment is appropriate.

Alcohol appears twice on the NHS dehydration page, and both mentions are relevant.

It is listed among the causes of dehydration, alongside being sick or having diarrhoea, being in the sun or a hot environment too long, sweating a lot after exercising, having a high temperature, and taking medicines that make you pee more.²

And it appears in the treatment advice: if you have symptoms of dehydration you should drink fluids, avoiding caffeinated drinks and alcohol as both will dehydrate you.²

The symptoms are the familiar ones: feeling thirsty, headache and feeling light-headed, dark yellow strong-smelling pee, peeing less often than usual, feeling dizzy or light-headed, feeling tired, and a dry mouth, lips and tongue.²

Two additional points. If you are still on weight management treatment, gastrointestinal effects and fluid losses are already a consideration, and a heavy night layered on top of them is the combination most likely to leave you unwell. And a hangover reliably removes both the activity and the meal structure from the following day, which is where the real cost sits.

The NHS advice contains the practical structure, and it is not abstinence.

Spread your drinking over 3 or more days if you regularly drink as much as 14 units a week, and if you want to cut down, try to have several drink-free days each week.¹

Both of those are more achievable than a target that reduces every occasion. Drink-free days in particular tend to work because they are binary and easy to plan, whereas "drink a bit less each time" requires a decision every round.

A few other things help.

Know your usual number once. Most people have never calculated it. Doing the arithmetic on a typical week, once, is more informative than tracking indefinitely.

Watch the strength, not just the volume. The NHS makes the point directly: the units in a drink depend on strength as well as size, with a pint of strong lager containing 3 units against just over 2 for a lower-strength one.¹

Plan what follows. If the meal after drinking is the larger part of the effect, deciding what it will be in advance is more effective than deciding how much to drink.

Do not use it for stress or low mood. The NHS advises against using alcohol, cigarettes, gambling or drugs to relieve a low mood, since these can all contribute to poor mental health, and lists drinking or smoking more among the behavioural changes stress can cause.⁴⁵

That last point is the one that most often needs addressing rather than the quantity. If drinking has increased alongside a period of stress, reducing the drinking without addressing the stress is unlikely to hold.

Before deciding whether to change anything, it is worth establishing what your normal is, because most people estimate it badly in both directions.

The NHS gives you the tool: strength (ABV) multiplied by volume in millilitres, divided by 1,000, gives the units in any drink, and the ABV is printed on cans and bottles, sometimes as "vol" or "alcohol volume".¹ Working through a typical week once takes about ten minutes.

Three things tend to emerge from that exercise.

Home measures are larger than pub measures. A generous glass of wine poured at home can be close to double a small pub glass, and since a 750 ml bottle at 13.5% contains 10 units, the difference between three and four glasses from a bottle is substantial.¹

Strength varies more than people expect. The NHS's own comparison makes the point: a pint of strong lager contains 3 units, while the same volume of lower-strength lager has just over 2.¹

The weekly total is concentrated rather than spread. Most people's units arrive on two or three days rather than being distributed, which is exactly the pattern the NHS advice addresses when it suggests spreading drinking over 3 or more days for anyone regularly drinking as much as 14 units a week.¹

None of that requires a decision on its own. It simply replaces an estimate with a number, which is the only basis on which a sensible decision can be made.

Two other reasons to keep an eye on this, both from NHS sources and both relevant to people who have been through weight management.

Drinking too much alcohol is listed among the things that increase your chances of having high blood pressure, alongside age, close relatives with high blood pressure, ethnicity, an unhealthy diet especially one high in salt, being overweight, smoking and long-term stress.⁶ High blood pressure usually causes no symptoms, and the only way to find out if you have it is to get it checked.⁶

And NICE's dietary framing applies to alcohol as much as to food: flexible and individualised approaches that achieve nutritional balance while managing energy intake, taking food preferences, personal circumstances and comorbidities into account, with restrictive nutritionally unbalanced approaches advised against.⁷ A plan that eliminates something you value is a plan with a short life.

How much alcohol can I drink and still maintain my weight?

The guidance does not answer that question in weight terms. What it gives is a health-risk limit: no more than 14 units a week on a regular basis, spread over 3 or more days, with several drink-free days if you want to cut down.¹ For weight specifically, the NHS principle is the general one, that maintaining weight means calories used matching calories eaten and drunk.³ Working out your usual weekly units is the practical first step.

Is wine or spirits better for weight than beer?

The unit calculation is the useful comparison rather than the drink type: strength multiplied by volume in millilitres, divided by 1,000.¹ The NHS's own examples show how much strength matters, with a pint of strong lager at around 3 units against just over 2 for the same volume of lower-strength lager.¹ Mixers add sugar on top, and the NHS advises against drinks high in sugar too often and suggests sugar-free versions where available.

Does alcohol affect sleep enough to matter?

There is no direct NHS statement linking alcohol to sleep quality, so no specific effect is claimed here. What the NHS does say is that longer-term sleep problems may affect your mood, appetite, relationships and social life, and that getting enough sleep supports mood, energy, immune system and overall health.⁸ Whatever the mechanism, most people can observe for themselves whether their sleep and their following day are affected, and that observation is a reasonable basis for a decision.

What if I am still on weight management treatment?

The NHS guidance on units applies as it does to anyone. The additional considerations are that alcohol is listed among the causes of dehydration, and that gastrointestinal effects and fluid losses are already a feature of these medicines, particularly around dose increases.² A heavy night in a week when you are already unsettled is the combination most likely to leave you unwell. Ask your prescriber or pharmacist about anything specific to your medicine.

I have been drinking more since I stopped treatment. Is that common?

It is a recognised pattern in a general sense, since the NHS lists drinking or smoking more among the behavioural changes stress can cause, and advises against using alcohol to relieve a low mood because it can contribute to poor mental health.⁴⁵ If drinking has increased alongside a difficult period, the more productive intervention is usually the underlying situation rather than the drinking itself. The NHS suggests talking to a friend, family member or health professional, and gives the Samaritans number, 116 123, for anyone who needs someone to talk to.⁵

Work out your usual weekly units once, using strength multiplied by volume divided by 1,000, and compare it with the 14-unit guide.¹ Most people are surprised in one direction or the other, and either way you now know.

If you want to reduce, start with drink-free days rather than smaller drinks, since that is the NHS's own suggestion and it is easier to plan.¹

And if drinking has crept up alongside stress or low mood, address that first, since the NHS specifically advises against using alcohol to manage either.⁴⁵

This guide is for general information only and does not constitute medical advice, diagnosis or treatment. The information here describes general clinical context based on UK regulatory sources cited above; it is not a recommendation for any specific medicine or treatment, which can only be made by a prescriber following individual assessment.

If you are considering treatment, speak to your GP or pharmacist, or arrange a consultation with a Cloud Pharmacy clinician. Prescription-only medicines are issued only after clinical assessment and where appropriate.

If you experience side effects from any medicine, you can report them through the Yellow Card scheme at yellowcard.mhra.gov.uk.

References used in this guide:

• Source: NHS website (nhs.uk).
• Contains public sector information licensed under the Open Government Licence v3.0.