“The body functions best at a certain temperature and when that temperature rises, we start sweating and losing fluids, which is our body’s natural reaction in an attempt to cool down,” explains Dr Ross Perry, GP and medical director of Cosmedics.
“When we sweat excessively, it can lead to dehydration which can become dangerous, therefore it’s important to stay hydrated to keep our bodies working and healthy.”
How do you know if you’re at risk of dehydration?
“Signs of being dehydrated include headaches, dizziness, dry mouth, tiredness, occasionally nausea and low blood pressure,” Dr Perry says.
Drinking enough water is the obvious solution – the NHS recommends six to eight glasses per day for an adult – but what if you’re not in the habit of sipping so much? Or you don’t like the taste of water? And do tea and coffee count?
Here, doctors share seven ways to make sure you stay hydrated during a heatwave…
1. Don’t wait until you’re thirsty
“Stay ahead of your thirst by recognising your own feelings of thirst, such as a dry mouth or feeling lethargic, and aim to drink to avoid them rather than to treat them,” says Dr Perry. “Don’t wait until you’re thirsty to reach for a drink, sip water continuously throughout the day and when you wake up during the night.”
Dr Sanjay Mehta, GP at the London General Practice, says: “Keep a bottle of water or a suitable alternative on you throughout the day.”
During a heatwave, he recommends: “Be even more vigilant and aware of your intake volume, and try to drink at least 20% above your usual intake to compensate for fluid loss through sweat.”
2. Peek at your pee
Another indicator that you need to up your hydration levels is the colour of your urine.
Dr Perry explains: “The darker it looks, the more water you need to be consuming. Keep an eye on the colour and smell. If it’s yellow looking with a strong smell, the chances are you’re dehydrated and need to be drinking more.”
3. Eat hydrating snacks
As well as glugging liquids, you can increase your intake by munching snacks with a high water content.
Dr Perry says: “Think berries, watermelon, nectarines, and peaches, which are all packed full of water, rather than carb-laden foods which can be packed full of salt and make you feel more thirsty.”
4. Add some flavour
Fizzy drinks and squash can be high in sugar, so choose flavoured drinks carefully.
“Try flavouring your water to make it more enjoyable, add slices of lemon, cucumber, or strawberries,” Dr Perry suggests. “If you’re not a fan of plain drinking water, milk is a good choice, as it’s more hydrating than water or sports drinks, due to its source of protein, carbohydrates, calcium, and electrolytes.”
Or try freezing your own ice lollies from fresh fruit juice or smoothies, so you have a snack that’s cooling and hydrating.
5. Avoid alcohol
“Avoid drinks that dehydrate you further, including alcoholic drinks,” says Dr Mehta. If you are drinking, try to match each alcoholic beverage with a glass of water.
Dr Perry recommends: “Cut down on alcohol, especially during a heatwave, as it will only make you more dehydrated, and exacerbate headaches and tiredness.”
6. Limit caffeine
Caffeinated drinks aren’t as dehydrating as you might think – as long as they’re consumed alongside water.
Dr Perry says: “Coffee and tea are fine to drink to stay hydrated, just make sure you’re not having too much caffeine throughout the day.”
7. Use your phone
“To remind yourself to drink more water, try downloading a hydration-tracking app, which will keep you on track with the number of fluids your body needs,” says Dr Perry.
Apps available on both Apple and Android devices include Water Reminder (search the Apple or Google Play stores) and WaterMinder.
Alternatively, on heatwave days, set an alarm on your phone calendar every hour, to remind you to keep sipping.