With heatwaves making the headlines and many of us jetting off on holiday to countries facing seriously scorching temperatures, keeping hydrated is key. But how much should we be drinking? And what about during heatwaves?
To help keep you cool, calm and hydrated wherever you’re spending the summer holidays, here’s what you need to know – and drink! Plus, how to spot the difference between mild dehydration and something more severe.
Why is it important to stay hydrated?
Water makes up two thirds of our body. It is vital we drink enough fluid to maintain a healthy balance.
Water keeps us alive – it’s that simple, explains ZoomDoc GP, Dr Leah Austin.
‘Water makes up about two thirds of our body and to stay healthy, hydrated and be able to function we need to replenish lost fluids caused by moving, sweating, going to the toilet etc. If we don’t, we become dehydrated, which can be serious, even fatal,’ she says.
Luckily, dehydration is pretty easy to avoid, by drinking water. But in the heat and when we’re busy or neglect ourselves, it can be something many of us either forget to do, or don’t do often enough.
How much should we drink each day?
Water is a healthy and cheap choice to keep you hydrated, but other drinks can also count towards your fluid intake.
NHS guidance recommends drinking between 6–8 glasses of water every day to stay hydrated. However, some may find that’s not enough.
‘The best way to know how much you personally need to drink to stay hydrated is by checking the colour of your pee,’ says Dr Leah.
‘If it’s a clear pale yellow colour then you’re getting enough fluids, but if it’s darker than this and strong-smelling then you’re dehydrated and need to drink more,’ she says.
As for what to drink, watch out for fruit juice, fizzy drinks and cordials, which have sugars in them. The easiest and healthiest way to hydrate is with water, but NHS guidance does say that ‘water, lower-fat milk and sugar-free drinks, including tea and coffee, all count.’
Caffeinated drinks have diuretic effects meaning they actually cause the body to get rid of fluid. There is some evidence that they still count towards hydration, but it’s best not to rely on tea and coffee to hydrate you and don’t exceed 200ml (roughly 2 cups of instant coffee) if you’re pregnant.
You’ll get some hydration from food, such as soups, stews, fruits and vegetables but again, ‘don’t rely on this to get your daily quota,’ says Dr Leah.
Should we drink more during a heatwave?
Your body loses liquids through sweat and perspiration and water can replace these vital liquids.
Absolutely. NHS hot weather guidance says, ‘if you’re active, or if the weather is particularly hot, there’s a greater risk that you will become dehydrated. To stay hydrated, you should increase your fluid intake.’
There’s no set amount to increase it by but keep a bottle of water near you and take regular sips to prevent dehydration.
‘If you’re worried, keep an eye on the colour of your pee (as above). Doing this really is the best gauge for your own personal hydration levels,’ says Dr Leah.
What are the signs and symptoms of dehydration?
Thirst, headache, and dry mouth are all signs it’s time to reach for water or a sports drink that’s low in sugar and high in electrolytes.
Dehydration is a sign your body doesn’t have enough water and although it can be easily remedied (by drinking water or even rehydration salts), it can also become severe pretty quickly so knowing what to look out for is important.
Signs of mild dehydration often include:
- feeling thirsty
- headaches
- tiredness
- dizziness
- dry mouth and eyes
- lack of concentration
- pain during urination or urinary tract infections (UTIs).
Signs of more severe dehydration can include:
- exhaustion
- confusion
- loss of consciousness
- not needing to pee for hours
- a weak or rapid pulse
- fits or seizures.
What else can cause dehydration?
As well as hot weather and not drinking enough, if you have a sickness bug with vomiting or diarrhoea, you can easily get dehydrated, which can make you even more unwell.
‘If you’re unwell and struggling to keep fluids down, just take sips of water when you can and build up to bigger amounts once things settle a bit,’ says Dr Leah.
Once you’re over the worst you can take rehydration sachets such as Dioralyte to replace lost salts and help you rehydrate faster.
Dehydration can also be caused by
- diabetes
- drinking alcohol
- spending time in the sun
- exercising
- fevers
- some medications.
When to see the doctor
Severe dehydration is a medical emergency. It needs to be treated right away with IV fluids in a hospital.
Mild dehydration will usually go once you top up your fluids, ie drink more water. However, if you’re regularly getting dehydrated but don’t know why, or feel particularly thirsty all the time, this can sometimes be a sign of other health conditions, such as diabetes or Sjogren’s syndrome, which your GP may want to rule out.
‘Severe dehydration is a medical emergency and requires immediate medical attention’, says NHS guidance.
If you or someone you know is severely dehydrated, call 111 or 999 immediately.
For any hot weather health concerns you can always speak to ZoomDoc. Our GPs are on the end of a phone at a time that suits you. Simply download our app to talk to a doctor today.