The UK has experienced some of the highest temperatures in July on record this week.
But while the sun is a good excuse to get out and about, the heat can play havoc on a person’s health.
Dehydration is a high risk, so to avoid this it’s important to drink plenty of water.
On a normal day people need aound 1.5 to 2 litres day, which is about eight 10 glasses.
But how much should you be drinking during a heatwave?
If you’re in the heat during the day you can become dehydrated quicker, so drink more often and aim for at least two litres, Dr Kim Glass, lead GP at Bupa Health Clinics, advised the Evening Standard.
She said: “It’s very unlikely that you’ll drink too much water, but if you’re going to the toilet a lot and your urine looks really pale, you’re probably drinking more than you need.
“If you’re sweating a lot due to het and begin to feel signs of dehydration then, as well as replacing your fluids you may find you need a recovery drink such as an electrolyte or low-sugar every drink.”
The guidelines set out in the UK refer to the amount of fluids a person should have, not just water.
Bupa explains: “You can get this from her and other drinks, such as milk and fruit juice.
“Water in food also counts – fruit and vegetables contain lots of water.
“Cucumber and lettuce have the highest water content of any food – a massive 96 per cent. Tomatoes are also packed with water – they’re about 95 per cent water.
“Just adding some salad to a sandwich can top your hydration levels up.”
The exact amount of fluid you need can depend on a number of things.
Your age affects how well your body can balance water and salts, and as you get older, you store less water.
Men need more water than women because women have a higher proportion of body fat.
If you exercise more you need to drink more.
You also need to drink more if it’s hot and you’re sweating water out of your body, if you’re pregnant as you’re more likely to develop constipation, and if you’re following a special diet or low-calorie diet – but ask a dietician for advice.
Dehydration occurs when your body loses more fluids than you take in, and a common cause is when you’ve been in the son too long.
If dehydration isn’t treated it can get worse and become a serious problem. It can cause fits, brain damage and even death.
So what are the symptoms of dehydration, and when should you call 999 or go to A&E?
The NHS lists six symptoms of dehydration in both adults and children to recognise.