Temperature is the first thing we check in the morning before we leave the house. Temperature affects our choice of clothes, our shoes, what we decide to bring etc. It is most likely to be a factor to make or break our day. So why aren’t we checking the temperature of our bedroom before going to sleep? Studies have shown that the indoor temperature can massively influence our health, sleeping patterns and comfort.
Our body core temperature changes during the night, as it does during the day. However, the average temperature that we have during the night is a couple of degrees lower compared to our day temperature. You might think that waking up in sweat means that you were hot the entire night, but that is not true. Our heat drops around midnight, which is like a signal to our brain, that it is time to sleep. In the circadian system, this means that the production of melatonin begins, which is a hormone that regulates sleep. This indicates a drop in body temperature, up to a few degrees.
If we want to help our natural cooling system to kick in, we need to keep our room temperature at a lower level. If it is too high our body will not have the possibility to drop the heat and will not give our brain the signal to shut down and rest, and we all know that the value of sleep is exponential to healthy living. Of course, this is not the only factor involved in the ‘’good sleep’’ scenario. You should also have a quality mattress or a noise machine that will send you off to dreamland. However, the room temperature is a critical factor that can keep us up all night if we are not aware of its importance.
Best Temperature for Sleep
While our body maintains a steady 35 C to 36 C, the temperature of the room needs to be between 19 C and 15 C. There is a difference between adults and babies, as babies have the best sleep between 21 C and 18C, and it is because babies generally have a higher body temperature than adults.
While we sleep our body temperature gradually declines, and it is the lowest at 5 AM. It might not be a coincidence that the lowest temperature during the day is also at dawn. This drop in temperature might be an evolutionary adaptation system, so messing with that could lead to a number of sleep disorders. There is, of course, a limit to where the lowest temperature needs to be. If it is too cold, the organs and the brain can slow down too much which can lead to a number of health issues.
So, what does this mean? Keep the room temperature above 13 C and below 24 C as it is a sweet spot that is said to provide the best quality of sleep. You can choose from this range and see which temperature works best for you. Is it more 20 C or 15 C?
If you usually sweat during the night, you should set the temperature a bit lower. If you sleep hot, try to get a pillow and a mattress that release body heat instead of retaining it, as they won’t warm you up during the night. Additionally, try to consider what you wear in bed. Warming PJs or a sleeveless nightgown have different effects on the body temperature just because of the materials and level of coverage.
Benefits of Sleeping In a Colder Environment
Some of the main reasons to sleep in a colder environment are that we tend to fall asleep earlier, our metabolism becomes faster which ultimately gives us a chance to avoid gaining weight, having insomnia and sleep problems.
One of the best reasons by far can be linked to a quicker and easier entering to the REM phase. REM is a specific phase of sleep where muscle tone is down, and we enter a dreaming sequence. During this phase all the information from the day is stored in long term memory, so skipping this phase during the night can be harmful to our cognitive functions such as perception, memory, and coming to conclusions. Although this phase does not last the entire night, it comes in shifts starting at ten minutes, and gets longer in every cycle, lasting up to an hour.
There is also a non-REM phase where we are asleep but there is no muscle and cell regeneration. As REM and non-REM phases shift during the night, if our sleep is longer we will enter the REM phase more, which will ultimately lead to a bigger percentage of information stored, our concentration is increased the next day and the overall rest for our body tissue and cells is bigger. This is how a colder room helps, as it increases the overall time we spent sleeping and ultimately, the time we spend in the REM phase. There is a fun fact when it comes to the REM phase and core temperature of the body. We don’t sweat or shiver during the REM phase. This may be because of the muscle tone that is almost non-existent. Following on this, babies also don’t shiver even while awake. Scientists showed that babies warm up by dissolving ‘’brown fat’’ which is a tissue that is made to heat up the body. This may be why we don’t shiver in the REM phase as well.
While it is recommended to keep your room at a colder temperature than during the day, it is not recommended to that the temperature oscillates during the night. This is why you should avoid sleeping with the window open, as the outside influence can change the temperatures in the room by a few degrees. One other way to keep your room at a constant warmth is to close the blinds while sleeping. Sun will warm up a room faster when it is not bouncing back from the curtains. It is a technique often used in summer to cool homes. Lastly, consider wearing something on your feet, like night slippers or socks. Maybe this sounds odd, but it is proven we lose more body heat through our feet, hands, and head than any of our other extremities because we need the extra blood flow to keep these parts of the body functional.
While it is proven that there are a few factors that can help you get a better night’s sleep, the two that have stood out are lack of light and colder air temperature. Maybe this sounds like common knowledge, but since we live in a fast-paced world, we often need to be reminded to take a moment and shut the lights out, get a comfortable place to sleep and get a good pillow. At the end of the day, we all want to treat ourselves for a job well done, so why is good sleep overlooked so often? Being a night owl is not always the answer to getting tasks done.
Co-founder of Counting Sheep and Sleepaholic