Alcohol dehydrates you – so it’s important to stay safe if you are planning to drink during hot weather.

Heatwaves can be dangerous in their own right – and adding alcohol to the mix increases your risk of dehydration, heat exhaustion or heat stroke.¹

But, if you do decide to drink alcohol during especially hot weather, there are things you can do to keep yourself safe. Read our quick guide.

Keep it low risk

Come rain or shine, it’s important to stick to the UK Chief Medical Officers’ (CMOs’) low risk drinking guidelines. That means - for both men and women - no more than 14 units a week, spread over three or more days with several drink-free days, and no bingeing.

Summer evenings are longer, so if you are drinking, it’s a good idea to keep track of how much alcohol you’re having, to make sure you’re sticking to the guidelines.

Binge drinking – having a lot of alcohol in a short space of time – can be extremely dangerous.¹ Our bodies can only process roughly one unit of alcohol an hour - and less for some people. 

Heatwaves can affect anyone, but some people are more vulnerable than others, including people who are dependent on alcohol, people with diabetes, kidney disease, Parkinson’s, some mental health conditions and older people (especially those over 75).²
Advice on alcohol dependence

Drinking alcohol can affect your judgment too. So you may not recognise early warning signs of heat exhaustion or sunburn.

The free MyDrinkaware app can help you track your alcohol consumption, calculate units and calories, plan drink-free days and set goals to help you moderate your drinking – download it now for free.

Download MyDrinkaware app

Drink plenty of water

Alcohol is a diuretic, which means it encourages the kidneys to get rid of fluid.⁴ That’s why you tend to urinate (pee) much more when you drink alcohol.

Alcohol also makes you sweat more, because it interferes with your body’s ability to control its own temperature.⁵ Combined with the fact that alcohol makes you pee more,⁶ you can lose more fluid than you take in and become dehydrated unless you replace that lost fluid by drinking extra water.

Dehydration can cause headaches, dizziness, sickness and tiredness. Serious dehydration requires urgent medical attention – it can cause confusion and seizures.⁷

Limit the amount of alcohol you drink and drink plenty of water or soft drinks in between alcoholic drinks to prevent dehydration.

During a heatwave, this advice is even more important. So, as well as sticking to the Chief Medical Officers' low risk drinking guidelines, make sure you drink plenty of water to reduce the risk of dehydration, heat exhaustion or heat stroke.

Go alcohol-free, or low alcohol

Swapping a standard strength beer, wine or spirit for a low alcohol or alcohol-free version could help you cut your drinking – and you will be joining a growing number of people. Figures from 2021 show one in five UK adults used alcohol-free drinks as a way of moderating their alcohol consumption.⁸

If you’re looking for a way to cut down on alcohol without cutting it out completely, alcohol-free or low alcohol drinks could be right for you, and you’ll be less likely to get dehydrated during hot weather.

‘Low alcohol’ drinks contain 1.2% alcohol by volume (ABV) or less, while ‘alcohol-free’ drinks are mostly 0.5% ABV or less – so they aren’t suitable if you want to avoid alcohol completely.⁹

Cutting your drinking with alcohol-free or low alcohol

Swap a cocktail for a mocktail

If you’re thinking of having a cocktail, it’s important to know how many units of alcohol are in your drink - otherwise you could end up drinking more than you intended. You can check how many units are in your drinks with our Unit and Alcohol Calculator.

A good alternative, if you fancy a mixed drink, is to go for a non-alcoholic mocktail instead. We have some summery mocktail recipes that can get you started. Many bars and restaurants now sell a range of ‘virgin’ or alcohol-free drinks – including a growing number of alcohol-free bars.

For anyone watching their waistline, it’s worth knowing cocktails and mocktails can be high in sugar, making it easy to consume a lot of calories without realising it. Try alternating with low calorie soft drinks or still or sparkling water to help you cut down the calories.

If you do decide to mix alcoholic drinks at home for friends, you can use a unit measuring cup to avoid over-pouring – you can buy one from the Drinkaware shop. And if you are out, the bartender can advise on what measure of drink you’ve ordered.

Don’t drink and swim

While going for a swim may seem like a good idea to cool off on a hot day, don’t try to swim if you’ve been drinking any alcohol.

Alcohol consumption is known to increase drowning risk.¹⁰

Drinking alcohol impairs your judgement, balance and coordination¹¹ - seriously affecting your ability to get yourself out of trouble and making swimming very difficult.

A quarter of all adult drowning victims have alcohol in their bloodstream, according to the Royal Life Saving Society (RLSS).¹² Their research indicates that almost half (45%) of young people aged 16-25 who lost their lives to accidental drowning have alcohol and/ or drugs in their bloodstream.

The RLSS have a dedicated Don’t Drink and Drown campaign that aims to reduce the high number of university students who drown after drinking.