Why Does My Body Heat Up When I Sleep?

The information in this article is for educational purposes only and should not be considered medical advice. [Read our full health disclaimer]

Updated on February 16, 2023

A good night’s sleep is vital for our physical and mental health. After a good night’s sleep, we can complete our daily tasks properly. On the other hand, if you don’t sleep well, you’ll be feeling tired and sluggish the next day. This will make it difficult to concentrate and work or do chores. Therefore, it’s important to get 7-9 hours of high-quality sleep every night.

However, from time to time, every one of us experiences sleeping difficulties. One minute you’re snuggled up in your cozy bed, comfortably falling asleep, and the very next moment you start kicking off your blanket, sweating as if you’ve just run a marathon. So, the real question is: why do I heat up when I sleep?

woman in black and white floral bikini lying on bed

There are many different causes of night sweats such as sleeping with a partner, sleeping on a memory foam mattress, room temperature, sleep environment may have too many disturbances, hormones, and medical conditions.

Read on to find out what may be causing your sleeping difficulties. After tracking down the reason, you might just find a solution, too!

Why Does Your Body Heat Up When You Sleep?

As you may know, every night, the human body produces a hormone known as melatonin. This hormone regulates night and day cycles or sleep-wake cycles. However, what you might not know is that the human body temperature begins to decrease as sleep time gets closer.

Woman in Gray Tank Top Lying on Bed

Every day body temperature varies between 96.8 and 100.4 degrees Fahrenheit (36 and 38 degrees Celsius), and a normal circadian rhythm would have the body temperature begin to decrease from 8 p.m. until 5 a.m.

Some research has shown that the optimal sleeping body temperature is around 60 and 68 degrees Fahrenheit (15.5 and 20 degrees Celsius), however, the rate of temperature shifts is also very important.

The sleeping process occurs when the core body temperature is decreasing at the fastest rate, meaning, when the body loses heat at a maximum velocity. These shifts in body temperature send signals to the human brain that it’s sleeping time. However, in some cases, the body temperature doesn’t decrease at all. And if it doesn’t fall into the optimal range, it will be much harder for the individual to fall asleep.

Reasons You’re Heating Up While Sleeping

If you’re wondering how to control your body temperature, it’s best to understand what might prevent it from decreasing in the first place (in order to eliminate some of the reasons naturally). Here, we’ll give you some of the common reasons for extremely high body temperature during sleeping.

You Sleep With Another Person

Man and Woman Lying on Bed

If you’re sleeping with another person, the combined body temperature can increase the temperature under the covers, and even the temperature in the room. This applies to sleeping with pets, as well.

The human body is constantly emitting heat because our metabolism keeps working. This means that more bodies in a smaller space lead to a faster increase of the temperature in that area. The average body temperature is around 98.6 degrees Fahrenheit (37 degrees Celsius), therefore, if the room temperature is higher than this temperature, the body is going to absorb the heat from the room.

So, in order to get better sleep, and at the same time to continue sleeping with someone else, try to lower the temperature in your sleep environment.

You Sleep on a Memory Foam Mattress

Certain types of mattresses can make the body’s thermoregulation less efficient than others because they might trap heat between the mattress and the body. Mattresses that are made from memory foam, for instance, may cause you to feel higher body temperature during your sleep.

white textile on black textile

If you sleep on a memory foam mattress, your body’S excess heat is transferred to the memory foam so that it can warm up and mold to your body’s shape. Although this may make the mattress more comfortable, the heat that gets transferred back into your body may cause overheating.

However, there is a solution for this, because some mattress companies have added a topper over foam mattresses that are made of wool. This top layer acts like a thermoregulator for the body, decreasing the chances that you’ll suffer from night sweats and hot flashes.

Ambient Temperature

Some studies suggest that the optimal temperature of the room where you sleep should be somewhere between 60 and 67 degrees Fahrenheit (15.5 and 19.4 degrees Celsius). This is because the body regulates its own internal temperature as we sleep, by keeping a low body temperature during sleep and then slowly increasing it as a signal that it’s time to wake up.

white and gray thermostat at 19 5

By setting your thermostat at a lower temperature, you’re helping your body’s temperature regulation. On the other hand, if your room temperature is too high, it can obstruct the process and result in overheating (and low sleep quality). So, the solution is to keep the thermostat at a lower temperature or crack a window open for better sleep.

Sleep Environment

Melatonin secretion is also affected by the environment of our bedrooms. Melatonin helps regulate our natural cycle, so if the environment isn’t conducive for sleeping, it can be harder to get a good night’s rest.

To ensure that you get enough quality sleep each night, it is important to create an optimal bedroom environment with comfortable temperatures and low levels of noise and light. Investing in blackout curtains or an eye mask may also help reduce any external light sources that could disrupt your melatonin production.

Woman wearing an eye mask over eyes while sleeping

Medications and Medical conditions

Certain medications have side effects that may provoke an increase in body temperature, especially at night. Here are some of them:

  • prescribed antidepressants or other medications for psychiatric conditions;
  • medications for diabetes and high blood sugar;
  • diuretics;
  • medications that are used in hormone therapy;
  • steroids;
  • and some recreational drugs, like cocaine or ecstasy.

Some medical conditions may disrupt the hormone balance that regulates the metabolism and other processes in the human body. This can result in unwanted symptoms like night sweats or increased temperature sensitivity. Thyroid disease (hyperthyroidism or hypothyroidism), some types of cancer, chronic stress, obstructive sleep apnea, and coronary heart disease are some of the medical conditions that can increase your body temperature at night.

Certain infections, such as the flu, pneumonia, colds, and tuberculosis, can cause night sweats due to the fact that the most common symptom of these infections is a fever.

Hormone Level Fluctuations

The fluctuations of human hormones, especially female hormones, can result in hot flashes and night sweats.

During premenstrual syndrome (PMS), night sweats are very common because of the fluctuations in the levels of progesterone and estrogen in a woman’s body. Additionally, when women are in perimenopause or menopause, they may experience hormone-related hot flashes and night sweats due to the decreased level of estrogen and other hormones. Lastly, pregnancy is another stage where hormone fluctuations cause changes in blood flow and may lead to an increase in body temperature.

woman in white long sleeve shirt

You can decrease overheating problems if you sleep with less covers or use bed sheets that are cooler to the touch and more breathable. For instance, you may purchase bed sheets that are made from bamboo or cotton.

Activities You Do Before Sleeping

Pre-sleep activities can have a significant impact on the quality of sleep we get. Caffeine, exercise, sex, stressful activities and spicy food are all activities that should be avoided close to bedtime. Caffeine can increase our core body temperature, making it difficult for some to fall asleep.

Exercise and sex can also increase heart rate and body temperature, making it harder to relax and fall asleep. Stressful activities can cause blood vessels to constrict, causing skin surface temperature to drop and increasing core temperature. Spicy food before bedtime can affect the severity of sweating which may make it more difficult to drift off into a peaceful slumber.

It is important to be mindful of what we do before going to bed as these activities can have an effect on how well we sleep. To ensure a good night’s rest, try avoiding caffeine after lunchtime and late afternoon, exercising at least 3 hours before bedtime, and engaging in calming activities such as reading or listening to music instead of watching television or using electronic devices.

Eating light meals with no spicy ingredients close to bedtime will also help you achieve a better night’s sleep.

Tips for Cooler Sleeping

Here are some tricks that you can try before you go to sleep in order to sleep better and avoid overheating:

Avoid alcohol before you go to bed

Alcohol consumption before bedtime can be detrimental to your sleep quality and overall health. When drinking alcohol, your blood vessels dilate and your heart rate increases, which can lead to increased perspiration while sleeping.

tea filled white ceramic mug on white ceramic saucer

This can make it difficult to get a good night’s rest and can also cause you to wake up feeling dehydrated. Additionally, alcohol disrupts the natural sleep cycle by interfering with the body’s production of melatonin, a hormone that helps regulate the sleep-wake rhythm.

It is important to note that even if you don’t typically experience sweating when drinking alcohol, it is still possible for it to occur while sleeping. Alcohol consumption before bedtime can also increase the risk of developing other health issues such as high blood pressure or liver disease.

Therefore, it is best to avoid consuming alcohol before bedtime in order to ensure a good night’s rest and optimal health.

Drink a hot beverage, such as milk with honey or a cup of chamomile tea instead.

Practice Some Relaxation Techniques

Anxiety can be a difficult emotion to manage, and it can manifest in physical ways. One of the most common physiological responses to anxiety is sweating and feeling hot in bed. This is because when we experience fear or stress, our body’s natural response is to activate the fight-or-flight response.

This causes an increase in heart rate, body temperature, and other physiological changes that can lead to excessive sweating and feeling hot in bed.

woman in black shirt and gray pants sitting on brown wooden bench

It’s important to remember that this is a normal response to fear or stress, especially if you’ve experienced nightmares or have an overactive mind. It’s important to take steps to reduce your anxiety levels by engaging in activities such as meditation, yoga, or deep breathing exercises.

Additionally, talking with a therapist or counselor can help you better understand your anxiety and learn how to manage it more effectively. Taking these steps can help reduce the intensity of your anxiety-related sweating and feeling hot in bed.

Avoid Strenuous Exercises At Night

Exercising is an important part of a healthy lifestyle, but it’s important to be mindful of when you are doing it. If you are trying to fit in an exercise regimen after work, try not to do anything too strenuous before bedtime. This is because intense exercise can elevate your body temperature and make it harder for you to fall asleep.

Recent studies have shown that exercising regularly can help promote sleep, but an intense workout 60 minutes before bedtime can reduce the total amount of sleep overall and make you more likely to wake up during the night.

It’s best to stick with light or moderate exercise if you plan on working out close to bedtime. Low-impact activities such as yoga or stretching can help relax your body and mind without raising your body temperature too much.

You can also opt for a leisurely walk or jog around the neighborhood instead of more vigorous exercise routines like running or weightlifting. 

Invest In A Mattress With Cooling Properties

If you’re a naturally hot sleeper, investing in a mattress with cooling properties may be the way to go. A hybrid mattress is an excellent option as it combines the comfort of luxury foam with the airflow of springs.

person holding clear drinking glass

Stay Hydrated

Staying hydrated is essential for maintaining a healthy body temperature and overall health. The recommended amount of water to drink per day is 8 to 12 cups, but this should be increased on hot days when the body loses more water through sweating. To ensure adequate hydration, it is important to keep cold water nearby your bed at night. This will provide an easy way to rehydrate and cool down during the night.

Take A Hot Shower An Hour Before You Go To Bed

Taking a warm bath before bedtime can be an effective way to prepare for a good night’s sleep. It helps your body relax and cool down, which is essential for getting quality rest.

When you take a hot bath, your body temperature rises initially. As it cools down afterward, it signals to your body that it’s time to go to sleep. This is why taking a warm shower or bath an hour or so before bedtime can help you fall asleep faster.

Not only does taking a hot bath before bedtime help you relax and get ready for sleep, but it can also provide other benefits as well. For example, soaking in warm water can help reduce stress and tension in the muscles, which can lead to better overall health and wellbeing.

Additionally, the heat from the water helps improve circulation throughout the body, which can help reduce inflammation and pain associated with arthritis or other chronic conditions. Taking a hot bath hours before bed is an easy way to promote better sleep hygiene and overall health.

Wear Breathable Sleep Wear

When it comes to getting a good night’s sleep, the clothes you wear can make all the difference. Wearing comfortable pajamas is essential for regulating your body temperature and promoting comfort during sleep.

A Person Wearing a Stripe Pajama

Lightweight and breathable materials like cotton or silk are ideal for hot weather, as they wick away moisture and allow air to circulate around your skin. Heavier fabrics such as flannel should be avoided in warmer climates, as they can trap heat and make it difficult to cool down.

In addition to keeping you cool, wearing comfortable pajamas is important for helping you relax before bedtime. Look for clothing that fits well and feels soft against your skin so that you can drift off into a peaceful slumber without any distractions.

You may also want to consider investing in some cozy accessories such as a pair of fuzzy socks or a lightweight robe to complete your nighttime look. With the right pajamas, you’ll be sure to have sweet dreams every night!


Concluding Thoughts

There are many potential reasons on why do we heat up when we sleep. Before you try to fix the problem, it’s important to identify the cause. Here, we explained some of the things that could have an impact on your good night’s sleep.

Hopefully, you’ll be able to fix your sleeping difficulties naturally by changing your mattress, sleeping clothes, and bedding, decreasing the temperature in your bedroom or taking a hot bath. However, if your body temperature continues to rise while you sleep, the cause may be a health condition and you should pay a visit to your doctor.

Article Sources

  1. Troynikov, O., Watson, C. G., Nawaz, N. (2018). Sleep environments and sleep physiology: A review. Journal of thermal biology, 78:192-203. https://www.sciencedirect.com/science/article/abs/pii/S0306456518301335
  2. Lan, L., Tsuzuki, K., Liu, Y. F., & Lian, Z. W. (2017, August 15). Thermal environment and sleep quality: A review. Energy and Buildings, 149:101-113. https://www.sciencedirect.com/science/article/abs/pii/S0378778817317681
  3. Harding, E. C., Franks, N. P., & Wisden, W. (2019, April 24). The temperature dependence of sleep. Frontiers in neuroscience, 13:336. https://www.frontiersin.org/articles/10.3389/fnins.2019.00336/full
  4. Halson, S. L. (2008, March 25). Nutrition, sleep and recovery. European Journal of sport science, 8(2):119-126. https://www.tandfonline.com/doi/abs/10.1080/17461390801954794
  5. Avis, N. E., Crawford, S., Stellato, R., & Longcope, C. (2001). Longitudinal study of hormone levels and depression among women transitioning through menopause. Climacteric, 4(3):243-249. https://www.tandfonline.com/doi/abs/10.1080/cmt.
  6. Zhou, Q., Wang, B., Hua, Q., et al., (2021). Investigation of the relationship between hot flashes, sweating and sleep quality in perimenopausal and postmenopausal women: the mediating effect of anxiety and depression. BMC Women’s Health, 21(1):1-8. https://bmcwomenshealth.biomedcentral.com/articles/10.1186/s12905-021-01433-y
Bree Taylor - Lead Editor

Lead Editor

Bree is an interior designer with a passion for helping people improve their sleep quality.

She specializes in creating comfortable and functional bedroom spaces that promote a good night’s rest.

When she’s not testing mattresses or helping people get the best rest possible, Bree loves to travel and explore new cultures.

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