What’s The Best Temperature For Sleep?

Mary Sweeney - Updated on March 22nd, 2023

Temperature is Important

There are a lot of different components to a good night’s sleep. Some of these components are tied closely to how your bedroom is set up. Have you ever had a terrible night’s sleep? Do you suffer from insomnia? Did you know that the temperature of your room may have something to do with it? Science says that your thermostat plays an incredibly important role in the quality of the sleep that you get. So, let’s talk about sleep and room temperature!

What Happens When We Fall Asleep?

To understand the effect of temperature on sleep quality, it’s important to also understand the human sleep-wake cycle. A normal sleep cycle lasts about 90 minutes and can be broken down into two different types: Rapid eye movement (REM) sleep and non-REM (NREM) sleep. Within those two different types, there are 4 stages of sleep – here’s a breakdown:

Stage 1: This first stage of NREM sleep is a light sleep, lasting only a few minutes or so. Here, your body is preparing to fall into a deeper sleep, your eye movements slow down, and your brain begins producing alpha and theta waves. During this stage, you can be easily awakened since you’re only lightly sleeping.

Stage 2: During this NREM stage, you’re still lightly sleeping but your heart rate slows down, your muscles relax significantly and your body temperature decreases slightly. Eye movements will slow down during this stage, and your brain waves slow down with occasional increases in activity.

Stage 3: This NREM stage is restorative sleep, the kind that makes you feel refreshed. If someone were to wake you up during this stage, you would likely feel disoriented for a few minutes before recognizing your surroundings. Our eye movements slow down or stop, and it’s very difficult to wake us up. This stage is an important one – it’s where your body starts repairing muscle, strengthening your immune system, and other vital processes.

Stage 4: Rapid eye movement (REM) sleep. During REM sleep, our eye movements increase dramatically, as the name suggests. REM sleep is the stage where you dream the most, and it’s thought that the eye movements are related to the dreaming that you’re doing. During this stage, most of your muscles are in a paralyzed state, to keep you from acting out your dreams. Don’t worry though, the important muscles like your heart and diaphragm aren’t paralyzed and are working like they’re supposed to!

While the average sleep cycle lasts 90 minutes, you will go through several cycles of varying lengths during one night. During your first few sleep cycles, you’ll go through longer cycles of NREM sleep, followed by a few cycles of REM sleep. Research also shows that the time of day can affect what type of sleep you get. For example, it is thought that most NREM sleep happens between the hours of 11 pm and 3 am, and REM sleep more often happens between 3 am and 7 am.

How Are Circadian Rhythms Part of the Sleep Cycle?

Our bodies have internal clocks that every organ system uses to function on a daily basis. In terms of sleep, these clocks tell us when it’s time to be awake and when it’s time to go to sleep. They regulate our sleep cycles by giving us our circadian rhythms, which are the schedules our bodies follow for the daily physical and mental changes. Circadian rhythms regulate the body’s sleep cycles regulating the production of melatonin, the hormone that makes you feel tired. Melatonin is naturally produced by the brain when there is little to no natural light, usually at night. Its production decreases during daylight hours, which is why we feel awake during the day and sleepy at night.

How Much Sleep Do We Need?

Although you may be able to function on four hours of sleep, that doesn’t mean it’s healthy. An average adult needs 7-9 hours of sleep to get the most complete sleep cycles for optimal daytime functioning. However, it’s not just the number of hours you spend asleep that matters – it’s also the quality of the sleep you’re getting. That’s where room temperature becomes a factor.

Why is Room Temperature Important?

During the initial stages of sleep, your brain lowers your body temperature in preparation for the restorative stages of sleep. By keeping your room at a cooler temperature, you are helping your body achieve that optimal temperature faster, meaning you can spend longer in the restorative stage of sleep. If your sleeping environment is uncomfortably hot or cold, you are much more likely to awaken several times during the night, and you are less likely to spend enough time in REM sleep.

There are many suggestions as to what temperature is ideal for sleep, and the consensus is this – keeping the thermostat between 60-68 degrees Fahrenheit is thought to be optimal, with 65 degrees being a happy medium. If you have babies or toddlers in your home, the temperature range is slightly higher – between 65-68 degrees.

But what if you sleep just fine in a room that’s 70 degrees? Even if that is true, you may not be getting the optimal sleep quality that you would if you had a cooler sleeping environment. If you don’t like sleeping in a chilly room or if you need more tips to keep your room cool, here are some other things you can consider doing to help your body lower its temperature faster:

  • Keep a fan on. A fan in your bedroom can help circulate stagnant air, cooling you off indirectly. Added bonus: your room won’t feel as stuffy and your sleep quality may improve! 
  • Keep a glass of water by your bed. In addition to waking up thirsty in the middle of the night, you may need a refreshing sip of cool water if you wake up feeling hot. Keep a glass of iced water next to the bed – that way when the ice melts during the night, you’ll still have cool water to sip if you need it.
  • Sleep in lightweight fabrics. Skip the flannel pajamas and opt for lightweight, breathable pajamas like jersey fabrics. Sleep in shorts rather than pajama pants, and if you’re feeling really comfortable, sleep naked!
  • Get a cooling pillow. Cooling pillows usually come with a gel filling that keeps cool throughout the night. 
  • Take a warm bath, but not less than an hour before bed. Studies have shown that taking a warm bath can signal to your body that it’s time to relax. However, make sure that you’re taking that warm bath one to three hours before you crawl under the covers so that your body has time to cool off. If you take one too close to bedtime, your body will take longer to achieve its optimal temperature and you may have a harder time falling asleep.
  • Invest in breathable sheets or a cooling comforter. Believe it or not, there is such a thing as a “cooling” down comforter. When it comes to sheets, linen and percale fabrics will keep you comfortably cool throughout the night.
  • Get a cooling mattress pad. A cooling mattress pad is another great way to help your body regulate its temperature throughout the night.
  • Don’t exercise at night. Exercising naturally raises your body temperature and it can take a little while for it to come down. For this reason, exercising close to bedtime is not recommended. Instead, try to work out in the morning or afternoon to give your body ample time to recover.

The most important thing to remember is to keep your sleeping environment comfortable for you. Not everyone can sleep in a room that’s 60 degrees, so find a temperature in the recommended range that works best for you and your family. There’s no need for you to be shivering under your covers, so find that happy medium and add a blanket or two to your bed – you can always take them off later.

Room temperature plays a huge role in the quality of your sleep, as do many other factors. See our other articles for more helpful hints on getting a good night’s sleep.

References and Continued Reading