What is the Best Temperature for Sleep? | Casper

December 13, 2019 | Casper Editorial Team

This article is for general information purposes only and is not intended as medical or other professional advice.
Visit the link following each suggestion for its source. Casper has not independently verified the sources. 

The optimal temperature for sleeping is between 15 and 19 degrees Celsius for adults. If you find yourself struggling to sleep at night – either with beads of sweat or the shivers running through your body – you may be sleeping in the wrong sleep temperature range.

Body temperature and room environment play an instrumental role in the quality of our sleep. In fact, a recent Gallup/Casper Sleep Study found that more than half of Americans (57%) experience occasionally sleeping “too hot,” and being “too hot” is one of the top three causes of having a bad night’s sleep.Our sleep cycles are strongly linked to our internal heat distribution system, more commonly known as thermoregulation. If we sleep in an environment that is either too hot or too cold, it interferes with our bodies’ process of circulating heat and creates uncomfortable conditions for sleep.

Below is an overview of the recommended ideal sleep temperature range for each age group.

The ideal sleeping temperature range varies slightly with age. The optimal sleeping temperature range for seniors and children is a little warmer at 19 to 21 degrees and 18 to 21 degrees , respectively. A lot of this will depend on personal preferences, as some people naturally sleep hot while others prefer it cold in their sleep environment. This is particularly important to note, as the Casper/Gallup study indicated that hot sleepers  are more likely to fall short on the recommended eight hours of sleep than are those who sleep with a comfortable temperature throughout the night.

It’s perfectly normal to set your room temperatures above or below these recommended temperatures until you feel comfortable. However, the best temperature for sleep is usually cooler.

Why Cool Temperatures Are Better

Sleeping in a cooler temperature helps improve sleep quality. Throughout the day, our bodies fluctuate between 2 and 3 degrees. When we lie down in bed, our core body temperatures drop, signaling to our brains that it’s bedtime. Maintaining a cool bedroom temperature helps facilitate our body’s natural cooling process.
A chart showing body temperature fluctuations by day
According to a study in the International Journal of Environmental Research and Public Health, participants who slept within a scorching range of 35.5 and 37.8 degrees Celsius had a shorter sleep duration and shallower sleep. Conversely, studies found that a drop in core body temperature before bedtime is more likely to trigger sleep onset, the transition between wakefulness and sleep, and increase deep sleep. Interestingly, the Gallup/Casper Sleep Study also found that adults under 30 are more likely than those older to say being “too hot” led to a bad night’s sleep.
In addition, cooler temperatures can facilitate REM (rapid eye movement), the stage of sleep where our muscles relax and we begin to dream. When we change our sleep environment to a comfortable range, we can ensure more restful sleep.

Keep Your Bedroom Cool in the Summer

When the warmer months roll around, our bodies can break into a sweat and we often cannot sleep since our bodies struggle to lower our temperatures. While it’s tempting to turn up the air conditioning, here are some tips to lower your bedroom temperature and cool your body.
A chart showing tips to keep your room cool in Summer. Chart items below.

  • Close the blinds – Up to 30 percent of unwanted heat comes from your windows. Close the curtains and windows when it is warmer outside to prevent heat buildup indoors.
  • Let in a breeze – Ambient temperatures tend to drop at night during summer months. After the sun sets, let in a refreshing breeze to cool your rooms.
  • Sleep on the lowest level of your home – Heat has a tendency to rise due to its density. Sleep in lower level rooms to avoid the updraft of warm air.
  • Use a fan – Fans can aid in sleep by lowering one’s body temperature and providing sleep-inducing white noise. If you have a ceiling fan, set it to run counter-clockwise – the airflow will create a wind-chill breeze effect to cool the room.
  • Wear light clothing – It’s important to focus on the temperature inside your body, not just your room. This means wearing light, breathable clothing, so your body heat isn’t trapped. If you’re up for it, you could consider sleeping naked, which has its own benefits.
  • Sleep on breathable sheets – Switching up your sheets can be a great way to improve your sleep. Airy linen sheets, for example, have moisture-wicking qualities designed to allow them to remain cool in the summer months.
  • Sleep on a mattress with cooling properties – It’s helpful to choose gel foam over memory foam mattresses like the Casper Wave, which contains airflow perforations and wool-infused covers designed to aid in temperature regulation.

What Should You Set Your Thermostat in the Winter?

Set your thermostat to 22 degrees Celsius during the day or when you are home. When you are about to head to bed, program the thermostat setting to between 19 and 17 degrees. It’s recommended to keep your room slightly warmer to counteract the drops in temperature at night.

As you’re preparing to sleep, here are a few tips to help you stay warm and comfy.
A chart showing tips for staying warm in Winter. Tips below.

  • Sleep in layers – Outfitting yourself in multiple layers is an effective way to keep your body comfortable even when it’s chilly.
  • Grab a warm comforter – A comforter or duvet adds additional layers and insulation material, making them a warmer choice than standard blankets.
  • Wear socks – Feet-warming socks have been shown to increase sleep efficiency and sleep duration and lower the number of awakenings during the night.
  • Cuddle up with your pet – Give your pup or kitten some love – studies found that sleeping with your dog can relieve insomnia and help you sleep more efficiently .
  • Sip warm tea before bed – Non-caffeinated teas like chamomile and passionflower can improve sleep quality and make it easier to wake up in the morning.

Create the Right Environment for Sleep

A comfortable environment is one of the most important elements to have at bedtime. Lying in your bed at the ideal temperature for sleep can help you drift off faster, enjoy better sleep quality, yawn a little less, and improve your overall health. It’s crucial to facilitate and maintain these optimal sleep temperature ranges in your room even during the day, no matter the season.

Looking for better sleep? Casper’s collection of mattresses, bed frames, and bedding are designed to help you create that sleep-ready environment in your bedroom.

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