How to sleep in the heat when it's too hot outside

As the weather hots up, we’re all looking for how to sleep in the heat. Fans are coming out of the attic and quickly being added to shopping carts around the country, but is there a better way to cool down before going to sleep?  

Summer is finally here and as much as we're all excited by the possibility of lighter mornings and evenings, there’s no denying that the increase in temperature plays havoc with our sleep. Lying awake in bed, throwing the comforter off, and then pulling it back on again, legs off the mattress, then back on. It’s not exactly a comfortable experience. 

It is possible to get a good night’s sleep this summer, fall asleep fast, and even beat the temperatures if you're wondering why heat makes you tired to begin with. Here, several sleep experts, nutritionists, and sleep scientists reveal how to sleep in the heat and sleep hacks to be aware of.  

Why is it hard to sleep in the heat?

It’s all part of our body’s response to danger, explains Dr Greg Potter (opens in new tab), sleep specialist, and chief science officer at Resilient Nutrition (opens in new tab). “It makes evolutionary sense that temperature affects our ability to sleep, for if it gets very hot or cold then you’d better not be asleep”, he says. “But this means you can use temperature changes to improve your sleep if you understand body temperature regulation.”

How to sleep in the heat

1. Have a hot shower

This seems like the last thing you should be doing if you're looking for how to cool down in a heatwave, but Dr Potter swears by it if you want to know how to sleep in the heat. “Unless it’s very hot outside, have a 10-minute hot shower one to two hours before bed,” he suggests. It works to cool you down because near the end of the day, there’s a fall in the temperature of your core, including your brain, which helps you fall and stay asleep. 

“Counterintuitively, this fall is related to a rise in your skin temperature in the evening, which results from increased blood flow to your extremities,” he says. “This speeds heat loss to the environment. So it makes sense to warm your skin in the hours before bed but then to sleep in a cool, well-ventilated room.”

2. Keep the windows open

While there’s an argument for closing the windows and sticking to other cooling techniques, especially if you’re suffering in allergies season, it’s one of the best ways to make sure that you’re at least getting a bit of breeze into the bedroom. 

“Before and during sleep, keep the windows open. If it’s noisy outside, you might benefit from earplugs,” Dr Potter suggests. 

3. Drink plenty of water

We all know that water is an essential nutrient for the body but when it comes to the hot weather, it’s more important than ever to stay hydrated - even during the night. 

But as Alison Jones, certified sleep consultant and expert at Sealy (opens in new tab), says, “Not only does staying properly hydrated help to lubricate the joints and cushion sensitive tissues throughout the night, it can also help you attain the drop in core body temperature that helps induce sleepiness, according to a study by the University of North Carolina (opens in new tab).” 

To make sure this happens, Alison suggests keeping a small glass of water on your bedside table or one of the best water bottles with a lid filled up. 

4. Keep your hands and feet out of the covers

The secret behind regulating your body temperature is keeping your body warm, but hitting core pulse points such as your head, neck, and wrists, Alison explains. Not only will this make you feel cooler in that moment, but keeping these extremities out of the covers will help you with how to get back to sleep if you wake up in the middle of the night as you won’t be too warm. 

“By keeping those key areas cooler, and away from the heat of the covers, it will help lower your core temperature,” she says. 

5. Apply a wet flannel to pressure points

If your AC isn’t working and your fan hasn’t arrived yet, why not go old school? Another great way to cool down so you learn how to sleep in the heat is running cold water over a flannel and resting it on these key areas, Alison says. 

“Applying a cold flannel to your head, neck and wrists will rapidly reduce body heat by effectively cooling the blood circulating around your body - helping you to feel cooler, faster.”

6. Choose a different duvet

If you want to have a comforter, otherwise known as a duvet, in the summer then opting for a hot weather-appropriate one is a good idea. Many of the best duvets are suitable for both the colder and warmer months, bridging the gap between seasons. 

“If you use a duvet in the summer, choose a cool one,” Dr Potter says. “Get one with a tog rating of less than five, for instance. If that’s still too warm or you don’t want to buy another duvet, try using just the cover and keep the inner handy in case you get too cool.”

7. Take a look at your mattress

While not everyone will be able to afford a new mattress as soon as the temperature changes, it’s worth looking into a heat-appropriate one if you’re due for an upgrade anyway. 

“Use a mattress and pillow that wicks away heat and sweat. In general, spring and hybrid mattresses are better at this than foam ones, and pillows should be made from breathable materials. If you’re going to upgrade your mattress or pillows, get ones with a free trial period,” says Dr Potter. 

And whatever you do, avoid traditional memory foam mattresses. “These are known to come with real heat problems,” says sleep technology expert for Dormeo (opens in new tab), Phil Lawlor. 

“There’s nowhere for your body heat to escape to and no ventilation. Mattresses with open structured memory foam springs have been proven to make the mattress eight times more breathable than other mattresses,” he says. “So if you are a hot sleeper, or just find it hard to get to sleep during summer months, this is really something you should consider.” 

8. Swap in sweat-wicking sheets

When it comes to your bed sheets and knowing how to sleep in the heat, eucalyptus wood, bamboo or silk are the best ones, explains James Higgins, sleep specialist, founder, and CEO of Ethical Bedding (opens in new tab). “When you become too hot, it can disturb your sleeping patterns and make you feel drowsy, so it’s important to pick a fabric which is body regulating,” he says. “Avoid cotton, as this tends to retain moisture and heat.”

Egyptian cotton is another material the best sheets are made of, as it’s especially lightweight and breathable, says Alison. But Egyptian cotton in light colors is a step above. “The colors of your bedding can also have an impact on temperatures, with pale colors like light blues and pinks coming out of top due to them being lighter in weight than dark colors.”

9. Sleep on the floor

If the heat is really getting to you, moving to the floor could help. "Heat rises," says Dr Tim Bond, a natural health expert from Puressential (opens in new tab). "Hot air is less dense and therefore it's lighter than cooler air, so it rises."

He suggests that sleeping downstairs if your bedroom is on the upper floor is a good idea, or just moving your mattress onto the floor. "It's likely to be cooler and potentially more comfortable."

10. Use a fan - with a bowl of ice in front of it

This is a pretty obvious one, and while there are some reasons why sleeping with a fan on might actually be bad for you, it’s still a useful tool to help you cool down in the summer - especially if you put a bowl of ice in front of your fan. Doing so will enable the fan to blow cold air around the room and onto your bed, instead of blowing warm air around. Just make sure the ice piles above the rim of the bowl, otherwise it won't work. 

Where you put it in your bedroom could also make all the difference, suggests Dr Potter. “A small bedside one aimed at the torso tends to work well,” he says, stressing the importance of keeping the fan close to you to feel its benefits.

11. Keep your bedroom dark

It’s tempting to throw open the curtains if it’s sunny outside, but letting light into your bedroom in the mornings could make it harder for you to sleep at night. 

It's best to keep your curtains closed, James says. “Use heavy curtains to block any light from windows during the day. Heat transfers through the windows and can build up during the day, so it’s a good idea to keep the curtains or blinds closed.” 

Doing so will keep the temperature of your room to optimum levels, he adds. “The temperature of your room should be between 60 to 67°F (15.6 to 19.4 °C). It varies depending on the individual of course, but most doctors recommend this as the best temperature for sleeping.” 

12. Sleep on your side

When it comes to sleeping in hot weather, try to sleep on your side if possible. "Try sleeping on your side if it's too hot to sleep at night," suggests Dr Bond. "Sleeping in this position means your body heat can escape easily as a larger portion is exposed to the air. This should help to regulate your body temperature and you should be much more comfortable like this."

13. Put your socks in the fridge

Yes, really. If the idea of sleeping without socks on isn’t for you, even in the summer, then put your socks in the fridge to cool down before heading to bed. 

“Your feet contain many nerve endings for your body,” James says. “Cooling your feet can lower the overall temperature of your body. Try putting your socks in the fridge and then wearing them before you go to bed to keep you cool.”

14. Sleep naked

Being too hot in bed is a huge barrier when it comes to getting a good night's sleep, so try sleeping without pajamas. You'll naturally feel cooler in bed at night without clothes than you would feel snoozing with clothes on, offering a better night's sleep overall. 

As the Sleep Council (opens in new tab) explains, if you're too warm when you're trying to go to sleep, your core temperature will struggle to drop. This means you won't trigger the so-called 'sleep mechanism', which is when your body temperature falls naturally after three or four hours, leading to a disrupted night's sleep. 

But ultimately, as there isn't a lot of research on the matter, it's about whatever you're more comfortable in. While some experts point to sleeping naked, others argue for keeping pajamas in constant use throughout the summer. 

“When the heat feels unbearable, it’s understandable our first port of call is to remove layers that we feel could be making us hotter,” Alison says. “However, sweat can stick to your skin when you sleep naked, making you feel uncomfortable and clammy.”

Instead, she suggests, opt for lightweight, wide-leg pajamas or a night dress that will help to combat sweats, ultimately leaving you cooler and drier throughout the night. 

15. Get your workouts in early

Whether it’s the 12-3-30 workout at the gym or Pilates for weight loss in the back garden, getting enough exercise every day is really important for our overall physical and mental health - but it can interrupt our sleep in hot weather. 

“Staying active is a proven way to improve sleep quality, no matter what time of year,” sleep expert Alison says. “However, avoid evening workouts and raising your core temperature in the run-up to bedtime. Instead, opt for an early morning workout when temperatures are cooler compared to mid-day or the early evening.”

16. Avoid eating late at night

When it comes to how to sleep in the heat,  what you eat - and when you eat - plays an important role. 

“Avoid eating anything too late at night,” says Anna Mapson, registered nutritional therapist and owner of Goodness Me Nutrition (opens in new tab). “When we’re digesting food, our body temperature can increase, so particularly when temperatures are high, leave around a three-hour gap between eating and bedtime if possible.”

This goes for some drinks as well. While staying hydrated is important, beverages that act as diuretics are not a good idea in hot weather. “That includes any tea, coffee, or dark chocolate from lunchtime onwards,” says Anna. “Caffeine has a long half-life, which means it stays in the system for a long time and it can affect the quality of your sleep long after you’ve drunk it.” Instead, opt for one of the healthy alternatives to coffee like decaf coffee, or mushroom coffee without caffeine - both work great over ice too.  

Is sleeping in the heat good for you?

Sleeping in hot weather, providing that your body maintains a healthy temperature, isn't bad for you at all. Our experts largely agreed that 65°F (18.3°C) is the optimum temperature for sleep, as it allows the body's natural processes to continue. 

Research from North China Electric Power University (opens in new tab) studied participants sleeping in much higher heat than this and their findings suggested we can handle a lot more heat than this. Their study participants slept at 82.4°F (28 °C),  89.6°F (32 °C), 96.8°F (36 °C), and 100.4°F (38 °C) heat and researchers found that the optimum temperature for sleeping was 89.6°F - the second coolest temperature - followed by 82.4°F. This is significantly warmer than many people in the UK and US will experience over the hotter months. 

Those who slept in the higher temperatures did experience interrupted sleep, however, with sleep quality lowest at 96.8°F and 100.4°F. At these temperatures, there was significantly more shallow sleep and they slept for less time, suggesting there was an impact on the sleepers' circadian rhythms in hotter temperatures. 

There were also issues with sleep calmness, difficulty falling asleep, sleep satisfaction rates were lower and they reported a less-than-adequate sleeping pattern.