Are you a hot sleeper and struggle to fall asleep at night?
Do you sweat a lot at night and need some relief?
You’ve definitely come to the right place.
What’s In This Sleep-Cool Guide
Table of Contents
In this guide, we take you through tips and ideas for sleeping cooler without having to buy an AC, whether a central or portable one. If you already have central AC, these tips can reduce your dependency on it and reduce your power bills.
People sleep hot for a wide range of reasons. Fortunately, there are just as many solutions you can try. Many of them are tricks that don't require you to buy anything. But we also recommend a few cooling products that can make a big difference in your sleep quality.
This guide also explains some possible reasons why you are sleeping hot and when it’s a good idea to talk to your doctor.
Why Do You Need To Sleep Cool?
You already know that feeling hot messes with your sleep. You struggle to fall asleep, resulting in insomnia, delayed sleep onset and daytime fatigue.
But you may not realize why your body needs to stay cool to sleep well.
Many body processes, including your wake-sleep cycle, are governed by the circadian rhythm. The circadian rhythm runs alongside the earth's 24-hour day, and corresponds to changing amounts of light.
When it gets dark, you'll feel your body getting tired and you'll start feeling sleepy.
Temperature also plays a big role in the circadian rhythm, particularly the wake-sleep cycle.
Research has shown that if your sleep environment is too hot (or too cold), it affects the onset of sleep.
If the bed or your bedroom is too warm, it prevents your body from dissipating excess heat and cooling down. Your core body temperature remains high, and this keeps your body from slowing down and falling asleep.
Lowering ambient temperature allows core body temperature to also drop, which in turn triggers sleepiness, partly by increasing melatonin production.
So as you turn off the lights and put away the bright sleep-disrupting gadgets, it's also important to keep yourself cool.
Why Do I Get So Hot During Sleep?
Here are some possible reasons why you sleep hot.
1. You Bedding Is Not Breathable
The most common reason people get uncomfortably hot in bed is stuffy bedding. Your bedroom may be cool, but that doesn't matter if your bedding traps body heat.
This happens if you have a duvet that’s too heavy or sheets that are not breathable. As your body releases heat, it gets trapped under the blankets, causing you to get hot.
Your mattress can also trap heat, creating an oven under the comforter. This usually happens with foam mattresses.
2. You Are a Naturally Hot Sleeper
Usually because of genetics, some people naturally sleep hotter than usual. If you are a naturally hot sleeper, other factors like stuffy bedding or hot weather can make you even hotter at night.
3. It’s Hot Outside
During summer, the nights may get warmer than usual, causing indoor temperature to go up as well. You can turn down the thermostat or use one of the energy-saving cooling techniques we explain further below.
4. Underlying Medical Condition
Some illnesses interfere with your body’s thermoregulation or elevate body temperature. These include flu, cancer, infection, and diabetes.
If you have an ongoing medical condition, find out from your doctor if it could be affecting your sleep temperature and what you can do about it.
In other cases, it’s not the illness causing you to sleep hot but the medication you are taking for it. This is something else you should talk to your doctor about, especially if you notice you’ve been sleeping hotter after you started taking the medication.
5. Humidity
If your bedroom is humid, it can make it feel hotter than it really is. That’s because high humidity prevents your body from sweating, which is one of your body’s primary cooling mechanisms.
6. Sleepwear
Check if your sleepwear is making you too hot. Either reduce how much you dress in bed (sleep naked or half-naked) or switch to lighter and more breathable sleepwear made with cool fabrics like cotton.
Other Causes
- Sleeping with someone. The combined heat output of two bodies in one bed can make you feel hot.
- Hormonal imbalances. These mostly affect women during PMS, pregnancy and menopause. They experience sudden spikes in temperature (hot flashes) and night sweats.
- Working out too close to bedtime. Exercise raises core body temperature. If you work out an hour or less before bedtime, you’ll still be feeling hot.
- Eating certain meals close to bedtime. Eating a large helping of steak or rice will increase body temperature because of digestion. This can affect your sleep if you eat too close to bedtime.
How To Cool Down Your Bedroom
Now, let’s talk about some ways you can sleep cool. We’ll categorize these tips into three categories: cooling down your bedroom, your bed, and your body. We’ll also recommend some products you can use to cool your bedroom or bed.
It’s a good idea to combine multiple techniques for best results.
Let’s start by cooling down the entire room.
Normally, you’d turn down the thermostat or install a portable or window AC. That’s the expensive way to cool down your bedroom.
An easier way is to increase airflow in the room. This will prevent hot air from stagnating around your bed, and can help bring in cool air from the outside. Here’s what you can do to increase airflow in your bedroom.
- Open a window to allow cooler air inside the room. Opening two windows opposite each other works even better because it creates a cross breeze, allowing hot air to flow out and cool air to come in.
- Use a fan to keep air flowing around the room. For faster cooling, crack open a window and face the fan towards it. It’ll drive out the hot air. You can also install a ceiling fan.
- If you have AC, you don't need to buy an extra fan. Turn on fan mode on the AC. It cools the room without using much power.
- Place an ice pack or a bowl of ice water right in front of your fan. As air passes over the ice or cold water, it’ll get cold and cool the room.
During the day when it’s hot outside, close the windows and curtains or blinds to prevent heat from building up inside the bedroom. When it gets cooler in the evening, open the windows.
Another way to cool the room is to switch to LED lights. LED fixtures produce less heat than other types of lights like fluorescent and incandescent.
On the same note, remove any gadgets or appliances that generate heat. These include laptops, mini fridge, and video game consoles.
How To Cool Down Your Bed
Your room may be cool, but your bed can still feel uncomfortably warm. As you cool the entire bedroom, you should also look for ways to keep your bed cool.
The most effective way to do this is switching to breathable and cooling bedding.
- Get cooling bed sheets made from fabrics like percale cotton, linen, or bamboo.
- Get a pillow that sleeps cool. If you are a particularly hot sleeper, avoid memory foam pillows. Get a latex or natural down pillow instead.
- Switch to a lighter summer comforter.
- Replace your mattress. Foam mattresses trap heat, making you sleep hot even if the room is cool. Switch to a cooling mattress made with materials like latex, gel memory foam, or pocket coils.
- If you don't have the budget for a new mattress, use a cooling mattress pad or topper to make your current one cooler.
You can also try sleeping on the floor or switching to a lower platform. Since hot air rises, it’ll be cooler closer to the floor.
How To Cool Down Your Body
As you cool down the room and your bed, directly cooling your body can help.
First, confirm with your doctor if the high sleep temperatures or night sweats are connected with an underlying medical condition or any medication you are taking. If either of these is the cause, your doctor might prescribe medication or change your prescription.
Treatment may also be available for women experiencing hormone-related hot flashes and night sweats. There are also supplements that can reduce the frequency and severity of hot flashes.
If you are just a naturally hot sleeper, there are a few ways to get your body to cool down during bedtime. Here are a few.
- Take a warm shower or bath just before bedtime. As your body cools down, it’ll trigger sleepiness.
- Drink cool water around bedtime. This will bring down your core body temperature. You can also drink ice tea (caffeine-free, obviously).
- If you are feeling really hot, a quick rinse in the shower with cold water will quickly cool your body. A cold swim also works.
- Dip a soft cloth or towel in cold or ice water and wring it so it’s not dripping. Place the towel on your chest, temple, neck or wrists - areas where veins are close to the surface of the skin. This will quickly cool down your body.
- Wear light and breathable sleepwear or sleep naked.
- Avoid eating and exercising too close to bedtime. Give yourself 1-2 hours before sleep to wind down and relax after working out or eating.
The Best Cooling Products For Hot Sleepers and Night Sweats
There are sleep products designed specifically to cool down hot sleepers and reduce night sweats. Because these products only cool down the bed, not the whole room, they are cheaper to operate compared to AC.
There are two types of cooling sleep products: passive coolers and active cooling systems.
1. Passive Bed Coolers
Passive bed coolers work by improving the breathability of your bed and reducing heat retention. They do not directly cool you down – they just keep your bed from getting too hot.
Passive bed coolers include cooling mattress toppers and pads. They are made from airy materials that don't trap heat such as perforated or open cell memory foam, natural latex, and wool.
Some advanced cooling pads contain special components that improve cooling performance such as heat-absorbing gel (often used in gel memory foam), copper, and phase change materials.
Cooling sheets, pillows (and pillow cases) and other cooling bedding also count as passive bed coolers.
Pros & Cons of Passive Cooling Systems
The biggest advantage of passive bed cooling systems is that they are cheaper than active systems and don't require any power to operate. So there are no maintenance costs.
They are also easy to use. Just lay a topper on your mattress, cover it with a sheet, and that’s it.
On the downside, passive bed coolers don't work for everyone. Extra-hot sleepers and those with severe night sweats may find that cooling mattress toppers and pads have limited effect.
Also, if you still have stuffy bedding or a heat-trapping mattress, there’s only so much a 1-3 inch topper can do.
2. Active Cooling Systems
Active bed cooling systems are like mini ACs just for your bed. They run on electricity and use air or water to cool the bed.
One of the most popular bed cooling systems is BedJet. It consists of the main control unit that sits under or next to your bed. The control unit has a fan that draws and cools air.
The cooled air is then carried to your bed by a hose that you place under the blanket or comforter. The cool air blows directly on your body, cooling you down and drying away sweat.
Most bed cooling systems use water instead of air. Water absorbs more heat than air, making it better for cooling.
The most popular bed cooling systems that use water are ChiliSleep's OOLER and Cube systems. They have a control unit with a reservoir to hold water and a fan to cool the water.
A pump pushes the cool water through a coil of thin tubes inside a pad. The pad goes on top of your mattress.
When cool water flows through the pad, it absorbs body heat and cools you down. It also reduces or prevents sweating.
There's a third type of active cooling system – bed fans.
Bed fans are just normal fans that circulate room temperature air. But unlike floor or desk fans, bed fans are designed to blow air directly under the blanket. You typically fix it at the foot of the bed and cover it with a blanket or comforter. It draws cool air from the room and blows it directly onto your body.
Bed fans are the cheapest active cooling system, and they work surprisingly well as long as your bedroom is cool. They prevent hot stuffy air from being trapped under the sheets. They are also great for drying away sweat.
Pros & Cons of Active Bed Cooling Systems
Active bed cooling systems are extremely good at keeping you cool. If you sleep really hot, experience severe hot flashes or have serious night sweats, get an active cooling system.
They work well regardless of how terrible your mattress is at cooling. You don't need to buy new bedding to sleep cool.
Another big advantage is that most active cooling systems can also warm the bed. The only exception is bed fans.
Active cooling systems have digital temperature control so you can set a cool or warm temperature. If you tend to get cold in the middle of the night or during winter, an active cooling and warming system keeps you comfortable all year long.
As for the downsides, active cooling systems are expensive. This is especially so if you want to get a split system for you and your partner. You’ll spend the cost of a new mattress to get a 2-person BedJet or OOLER system.
Secondly, they add a bit of noise to your bedroom because of the fan. But you can turn down the fan until it's almost inaudible.
Third, active cooling systems are limited in performance by ambient temperature and humidity. If it's too hot or humid in the room, they won't cool your bed very well. So you still have to keep your AC on or find some other way to cool down the bedroom.
Frequently Asked Questions
How does temperature affect sleep?
Lower body core temperature is one of the triggers for your body to get ready for sleep. If your body temperature remains at the normal waking level, you’ll struggle to fall asleep.
How do you lower body temperature quickly?
Take a cold shower to rapidly lower body temperature. You can also try going outside for a few minutes if there’s a cool breeze.
Another option is using a bed cooling system like BedJet or OOLER. Set the lowest temperature and highest fan speed to quickly cool the bed.
How do I sleep cool in the summer?
Keep windows and blinds or curtains closed during the day, and open them in the evening when it’s cooler outside. Use a fan to circulate air around the room. You can also place the fan close to an open window to drive out hot air and bring in cool air.
Wear light breathable clothes, or no clothes at all, to help your body stay cool. Also consider switching to breathable sheets and a light summer comforter.
Why do I get so hot at night?
A hot environment is the most common reason for sleeping hot. Turn down the AC to 65 degrees. If you don't want to use AC, open a window or two, or use a fan.
Other reasons for sleeping hot include bedding with poor breathability or a heat-trapping memory foam mattress.
Hormonal imbalances, illness, and medication can also make you hot at night, sometimes accompanied by night sweats.
How can I cool down before going to bed?
A cold shower or swim works wonders for cooling your body. If that’s too hardcore for you, a warm shower also works.
Avoid eating and exercising at least 1-2 hours before bedtime, and drink cold water before and during bedtime.
Final Verdict: What Is The Best Way To Stay Cool At Night Without AC
An active cooling system like BedJet or OOLER is the best way to stay cool at night. But if you are on a budget, there are lots of other things you can try that don't cost any money.
As a degreed engineer, I love new technology as much as you do (perhaps more). I also understand how to sort the best products from the rest. My team and I spend dozens of hours each week reviewing the best & latest products for your bedroom. Many are tested in-house, and others we break down based on our technical understanding. Whether you need a bed-cooling system, an adjustable bed, or a new CPAP machine – we've got you covered.