5 most (and 5 least) hydrating drinks to drink during the heatwave

Not all beverages were created equal, so here's what to chug for maximum hydration efficiency during a heatwave

Photos of water and a smoothie
(Image credit: engin akyurt / Douglas Bagg on Unsplash)

It's hot, hot, hot which means you might need to pay more attention to how much you're drinking to ensure your body stays properly hydrated – especially if you're trying to do any kind of exercise in the heat. But water can get boring after a while, and while it might seem like almost any beverage should help, the truth is some drinks are much more hydrating than others.

Here, qualified nutritionist Abi Roberts shared the most hydrating drinks to drink in the hot weather, and the dehydrating ones that'll do you more harm than good (information via Forbes Advisor). 

5 most hydrating drinks

1. Water

Sorry to be predictable, but your best option is (of course) just water. "It's essential to our survival and is the absolute best choice to maintain hydration," says Abi. For hydration on the go, fill up one of the best water bottles and take it with you, and the best water filters are great at sitting in your fridge and making your tap water taste better.

2. Caffeine-free tea

Caffeine is incredibly dehydrating, as we'll get onto in the next section, but caffeine-free teas are a different beast. They can be almost as hydrating as plain water, and many contain powerful antioxidants too, plus you can drink them hot or cold.

3. Low-fat milk

Low-fat milk is another excellent choice for hydration. "Milk is full of electrolytes which help to rehydrate the body after a bout of dehydration," says Abi.

4. Water infused with fruits or vegetables 

It's still water, but sticking some fruit or vegetables in there can jazz it up a bit on the flavour front, as well as adding extra vitamins and minerals. Abi's top suggestion is to add cucumber, which is one of the most hydrating foods you can eat (it's 96% water!). "Adding cucumber slices to your water boosts hydration even more whilst giving you the antioxidant properties and vitamins that cucumber contains," she explains.

5. Fruit juice

While they can be high in sugar, fruit juice still contains an average of 85% water, alongside health-boosting vitamins and minerals. Make sure you choose one labelled at '100% fruit juice' for the most hydrating effect, and beware smoothies, as we'll get on to next...

5 most dehydrating drinks

1. Alcohol 

Alcohol is super dehydrating so it's best to be avoided during a heatwace. "Alcohol removes water from the tissues in your body, which is why it’s common to feel like a shrivelled-up prune after a night of drinking," says Abi. The higher the alcohol content in the booze beverage, the more dehydrating the effect – so straight spirits (i.e. without a mixer) are the worst offenders, while something like a low-proof beer will be less so. Choose wisely for your next pub garden visit!

2. Caffeine 

Put down that iced latte: caffeine is naturally dehydrating, too. "High caffeine drinks (even when mixed with water) can end up dehydrating you or neutralising the hydration from the water content," explains Abi. Remember too that caffeine isn't just in tea and coffee; Fizzy drinks often contain caffeine too. These also often have a high sugar content, so overall they're just generally a horrible choice for staying hydrated.

3. Smoothies

While we've established that many fruits and vegetables have high water content, smoothies actually aren’t great for hydration. "When you combine lots of fruit and veg and blend it, the sugars are released, which makes it far less hydrating," says Abi. "When the sugar is contained within the fruit or veg, it can digest through your body more slowly."

4. Energy drinks

If you're flagging in the heat, you might reach for an energy drink to give you a boost. Unfortunately, energy drinks are often packed with caffeine, combined with a lot of sugar. Long story short, they're not a good choice on the hydration front.

5. Hot chocolate 

Probably not the beverage you'd naturally reach for during a heatwave, but hot chocolate is also pretty dehydrating. That's a result of the typically high sugar content, and it's even worse if high-fat milk has been added for flavour. "Opting for a low sugar and water-based hot chocolate makes it easier to stay hydrated," says Abi.

Ruth Hamilton

Ruth is a lifestyle journalist specialising in sleep and wellbeing. She has tested more mattresses than her small flat can handle and will talk at length about them to anyone who shows even a passing interest, and has had to implement a one-in-one-out pillow policy for fear of getting smothered in the night. As well as following all the industry trends and advancements in the mattress and bedding world, she regularly speaks to certified experts to delve into the science behind a great night's sleep, and offer you advice to help you get there. She's currently Sleep Editor on Tom's Guide and TechRadar, and prior to that ran the Outdoors and Wellness channels on T3 (now covered by Matt Kollat and Beth Girdler-Maslen respectively).

With contributions from