Sleep and Body Temperature — Are You Cool Enough?

The connection between sleep and body temperature, along with how hot or cold it is in your environment, is an important consideration for all chronic insomniacs.

Let’s start with room temperature. If your bedroom is either too hot or too cold, or if the temperature fluctuates between the two, your sleep might suffer.

Cold to hot to cold again?

The sleep and body temperature relationship can play out in several ways. Sometimes it’s obviously too hot or too cold (or too humid or too dry) to rest comfortably.

sleep friendly bedroomAnd sometimes, the temperature keeps seesawing from one to another. And while either extreme might interfere with sleep, you might find fluctuating temperatures even more troublesome. If you do manage to fall sleep, the change in bedroom climate could easily wake you up.

So you might go to bed feeling cold and pile on the blankets to feel comfortable. Then the heat comes on and the next thing you know, you are sweating and frantically throwing off the blankets.

Of course, then the heat goes off and you’re left shivering in the dark once again.

Fluctuating temperature is often due to a faulty thermostat, or the wrong location for it.

sleep and body temperatureFor example, if your bedroom is in a warm protected part of the house or apartment, away from drafts and cold air… but your thermostat is in a cold, drafty hallway near a window that can’t quite shut all the way… it’s no surprise why you’re too hot at night while family members or roommates in another part of the dwelling are too cold.

Replacing the thermostat or moving it is certainly easier than getting a whole new system.

You can also try closing or opening heater or a/c vents if possible.

If necessary, you can use a portable heater or cooler in your bedroom that operates on its own thermostat.

All of these could be solutions to the sleep and temperature problem. It all comes down to analyzing the air flow and temperature variations of your home and then adjusting or repairing your heating and cooling systems accordingly.

So What Is the Best Temperature for Sleep? Choose to Be Cool

If you had to choose between being too warm or too cold at night, apparently cold is the wiser choice. Studies have shown that cooler temperatures enhance sleep, while hotter temperatures interfere with it.

This is presuming, of course, that you have access to enough blankets to keep you nice and warm in a cool room. Comforters and polar fleece blankets are good, as they offer the most warmth with the least weight. Sleeping under a heavy pile of heavy blankets can get uncomfortable and even cause circulation problems.

So if you’re trying to decide the best sleeping temperature, set the thermostat lower than you would normally. You might sleep better and also save on energy costs.

Sleep and Body Temperature Variations

Of course, sometimes it’s your internal thermostat that’s causing the problem.

Are you a chilly person in general? If so, you might have trouble getting to sleep if you feel cold, especially if your feet are icy. This is why some chilly types like to take warm baths before bed in the wintertime. A water bottle or heating pad also helps.

If you’re a hot-blooded type, you may find a warm bath before bed completely unacceptable. Perhaps you have tried hot baths and find that they make your insomnia worse.

This is why it’s important to discover what works for you. You can only do that through experimentation, trial and error.

Insomnia and Menopause or Perimenopause

Of course a discussion of internal body temperature naturally leads to us lucky females. While hot flashes (and the chills that often follow) are primarily a menopausal symptom, many women experience a much milder version in the premenstrual hot flash, at any age.

In both cases, you go to bed feeling quite normal and wake up not only hot and sweating but even with a sense of near suffocation and needless to say, quite uncomfortable. You may change your clothes and open the window only to find a couple hours later that you are freezing.

Sleep and body temperature – The circadian connection

A sleep study done some years ago at Cornell Medical Center revealed that a significant drop in body temperature is associated with falling asleep.

The study was done in special environments with no day or night cues, so the participants did not know the time of day. They were not allowed to do strenuous exercise so that the relationship between sleep and body temperature could be more accurately recorded.

They all had rectal thermometers to give continuous readings of body temperature. And of course all their sleep episodes were monitored and timed as well.

(Sleep studies sound like so much fun, don’t they?)

As it turned out, the biggest drops in temperature occurred within a two-hour period before each of the longest sleep episodes.

Based on the results of tracking the sleep and body temperature connection, many sleep doctors now advise insomniacs to do certain things at night that might help lower the body temperature in the 90 minute period before bedtime.

These might include…

  • Taking a hot bath 90 minutes to 2 hours before bedtime, because body temperature drops quickly once you’re out of the bath.
  • However, avoid the hot bath immediately before bedtime because it might delay falling asleep by another hour or two.
  • Avoid strenuous exercise too soon before bed. While exercise is good for insomnia if done earlier in the day, it takes more time – sometimes several hours — for body temperature to drop down afterward.
  • When setting your sleep schedule, heed the signs of your own body. While you might not notice the actual drop in temperature, you might notice the feeling of sleepiness that results from it.

    But it’s easy to ignore this feeling when you think it’s “too early” to go to bed. So you stay up longer and miss that window of opportunity.

Conduct your own mini-sleep study now, by tracking the times when you feel the most sleepy. You can even take your own temperature in the evening to see if there’s a relationship between your sleep and body temperature.

Humidity and Dryness

While it’s not strictly a sleep and body temperature issue, humid conditions certainly don’t help insomnia. If you do manage to fall asleep, it is no pleasant experience to wake up in a pool of sweat.

On the opposite side, a very dry climate may cause allergies and breathing difficulties. Humidifiers and dehumidifiers can help regulate the moisture content of the air.

Note: if you live in a dry climate and need some moisture in the air, try a desktop water fountain. They will add humidity and offer a soothing water sound—two nice features combined in one!

Solving the Sleep and Body Temperature Problem

It seems like pretty simple stuff to tell you to add warm blankets, heaters, humidifiers, or dehumidifiers to make your sleeping space more comfortable.

But perhaps you have been avoiding confronting these temperature/ humidity issues because of money concerns (you can’t afford the appliances or remodeling that would make life more pleasant) or because you sleep with someone who has a different body temperature.

All I can say in such cases is, “compromise” and “prioritize.” If you need a better heating or cooling system, look upon this as a health requirement, rather than a luxury.

Return here to learn about more causes of insomnia lurking in your own bedroom.