Thermoregulation Guide: How Body Temperature Regulation Works During Sleep

Thermoregulation Guide: How Body Temperature Regulation Works During Sleep

Thermoregulation Guide: How Body Temperature Regulation Works During Sleep

Sleeping hot is a reality you’ve undoubtedly accepted when you use those remote-controlled fans hooked to the edge of most beds. 

And this is if cooling features were the primary factor in deciding your previous mattress choice or if you regularly sleep with your window open during the middle of winter. 

Yet, do you ever wonder why you get too hot at night? 

The effectiveness of the body’s temperature regulation during the night can significantly impact how well you sleep. 

Lack of sleep can affect your body’s capacity to regulate its temperature cycle, or a failure to regulate body temperature will result in increased insomnia. 

If you toss and turn all night trying to locate the one excellent position on your bed, your body may learn to ignore signals from your brain that tell it to cool down. 

This article might be a starting point for those interested in learning more about their bodies and breaking the pattern.

What Causes Our Sweat and Chills?

Our systems are very good at maintaining a comfortable temperature. If they sense that the usual ways of thermoregulation aren’t working, they’ll flip an “override switch” and either chill us down or warm our bodies more rapidly. 

Studies reveal that our ability to regulate our body temperature, or thermoregulation, is crucial to our survival in extreme environmental conditions.

A Harvard University study found that psychological and behavioural mechanisms play a role in maintaining a comfortable internal temperature. Shivering is a common response to cold that involves fast muscular contractions to increase body temperature. 

The study found that shivering generates as much as five times as much heat as standing. So, it’s not only a signal that it’s time to head indoors or wear a jacket.

The same also relates to how we lose water through sweat when it’s too hot, and heat causes us to sweat like cold makes us shiver. Evaporation of this water has a cooling impact that is relatively effective at reducing core body temperature.

A Biological Explanation

If you start sweating, you should eventually feel more relaxed, but when was the last time this was the case? Maybe not in the recent past. 

The Harvard School of Medicine explains that maintaining a stable body temperature is more important than maintaining a comfortable environment. 

Remember how terrible it feels when you’re dealing with a fever? Even though it’s only a couple of degrees, the disparity makes for an uneasy situation. 

What Would Occur if Your Body Temperature Constantly Followed Changes in the External Environment?

The optimal temperature for the human body is around 98.6 degrees Fahrenheit. 

Vasomotor control, essentially a fancy name for temperature regulation systems using our body’s circulatory system, plays a significant role in maintaining homeostasis, or a steady body temperature, in humans.

Our blood vessels dilate to cool down, radiating heat to the skin and other exterior tissues. The process causes us to sweat and feel warmer than usual. 

Despite heavy perspiration, your core body temperature will remain steady thanks to vasodilation, which increases blood flow by as much as ten times during exercise. 

By narrowing blood vessels, vasoconstriction helps the body keep its internal temperature stable by preventing heat loss. Even yet, you could feel the chill in your toes and fingers as the blood leaves your skin and muscles. 

Therefore, even while shivering and sweating may not improve your temperature regulation in the short term, they are essential in regulating your body’s internal temperature and preserving your state of homeostasis.

Monitoring Your Body Temperature Throughout Your Body’s 24-Hour Cycle

So, how does this relate to rest? When properly timed, thermoregulation ensures survival and signals to the brain that it is time to nap by maintaining an ideal resting temperature. 

German research found that whether you sleep in the day or night, your body temperature drops when you drift off to sleep. The brain cools down during slower-paced eye movement sleep phases. 

When our core body temperature drops dramatically, we may go for a blanket, lie down, and slow our breathing in preparation for sleep. An Australian research study found that people had more trouble falling asleep when they broke this pattern.

Due to the intimate relationship between the initial episode of none rapid eye movement each night and our circadian rhythm, research has shown that sleep deprivation can induce a disruption in the body’s natural temperature rhythm. 

As a result, our internal clocks lose sync and fail to tell our bodies to cool down and prepare for sleep at the appropriate times. Several illnesses can develop from this, but insomnia is the most prevalent. 

Evidence supports the idea that those experiencing vasospastic conditions, which alter the body’s capacity to contract and dilate blood vessels to regulate body temperature, have greater trouble sleeping than those lacking the disorder.

The body’s ability to fall asleep quickly and remain asleep after it has begun is related to several of these problems. 

For instance, your body might have been working hard to bring your internal body temperature down for sleep if, even after resting at a decent hour, you were still uncomfortable because you were somewhat too warm.

According to research done at Imperial College London, nesting behaviours relate to the human circadian rhythm alongside our non-rapid eye movement (NREM) sleep phase. As our core temperature drops, the study results show that we search for warm and cozy environments and nests before bed. 

The results trigger deeper NREM sleep stages by causing us to cool down as a reaction to the heat and warmth of our sleeping partners and blankets. Insomnia can occur if your body temperature doesn’t drop per your usual nesting routine or bedtime.

However, our systems are constantly working to keep us at a comfortable temperature. What is considered “normal”, 98.6 degrees Fahrenheit can vary by a couple of degrees throughout a typical day. 

Thermoregulation, which wakes you up as temperatures increase and makes you sleepy when the temperatures drop, can help control drowsy and alert states, based on information by Swiss experts. The temperature rises slightly in the afternoon and steadily drops a couple of degrees until right before we wake up.

Stages of Sleep and Thermoregulation

Sleep is not the only part of thermoregulation that’s important. Imperial College researchers discovered that the neurotransmitters in our brains that help trigger non-rapid eye movement periods also help the body cool down. 

The triggers help to clarify why NREM sleep is associated with more strict control of brain temperature during wakeful and rapid eye movement (REM) phases than the opposite is true during NREM sleep and why both functions are likely to coincide. 

The human circadian rhythm is crucial in regulating body temperature, improving sleep efficiency and the body’s ability to store and utilise energy.

Some research suggests that for depressed people whose body temperature cycles are not in sync, warming their bodies before sleep may enhance the quality of their restful sleep and aid in maintaining it.

Is There Anything That Might Impact Thermoregulation While Sleeping?

Healthline explains that different variables can affect your body’s capacity to maintain a steady internal temperature while one is sleeping. The following, for instance, are all possible causes of a drop in core body temperature:

1. Age

Age is among the most essential factors in a healthy core temperature. Children and older people are the clearest examples of how age affects core body temperature. 

When weighed against adults, children often have substantially greater metabolic rates, meaning their bodies transform food into energy much faster. As a result, children generally have a greater core body temperature than that of adults.

The converse is true for the opposite end of the age range. The average body temperature of a person over 65 is lower than that of a younger one. 

The peak temperatures of the participants in the study were more significant in the sixty-five to seventy-five age group than in the seventy-five to eighty-five age groups and above eighty-five age groups, indicating a progressive deterioration with age. 

Because of their lower baseline and weakened immune responses, older persons can be challenging to identify and detect infections.

This fact highlights the potential importance of constant fever monitoring in the care of older people. Standard methods of fever detection will fail because of their naturally lower body temperatures. 

That’s why it’s crucial to build a personal, one-of-a-kind baseline against which outliers may be more easily identified and addressed.

2. Sex

Carl Wunderlich, a German physician, first proposed the concept of a gender-based difference in core body temperature in 1868. 

According to Wunderlich, females often have higher core temperatures than males. Several hypotheses have been advanced regarding this phenomenon, including that women naturally have a larger body fat percentage than males and that this is due to the hormones involved in female reproduction.

Researchers in 1993 discovered no statistically significant gender differences in core body temperature. This 2019 review concluded that women, on average, record a slightly reduced core temperature compared to men. However, it glosses over this distinction as though it were irrelevant.

It’s important to remember that a female’s core temperature rises during pregnancy and ovulation and falls at the beginning of her menstrual cycle.

3. Time of Day

The average human body temperature varies widely during the day. The term for this is “diurnal variation.” The sun’s intensity is often lowest in the early hours and gradually increases throughout the day after one awakens, reaching its highest point in the late afternoon.

This fluctuation is in line with the rise and fall of metabolic rate, which is at its lowest while one is asleep and highest while awake and alert.

4. Physical Activity/Exercise 

For your muscles to move, they require energy. Muscle activity raises your core body temperature; the body will always try to cool it down by expelling the extra heat. 

When this occurs, the body’s core temperature rises because it cannot dissipate sufficient heat to keep it at a constant temperature.

Muscles generate more heat in response to increased workloads and activity. The rate at which your core temperature increases during physical activity is proportional to the strenuousness of the workout or activity and your metabolic rate. 

It is more difficult for one’s body to maintain a stable internal temperature when training in humid and hot settings. Exercising in cooler places creates the perfect environment for the onset of potentially fatal dehydration and heat disease. 

Experts advise against strenuous physical activity during hot weather because of this. Your body’s ability to release excess heat improves in proportion to the intensity of the physical activity you’ve trained it to perform. 

In light of this, it’s important to remember to take some time while exercising your body and drink enough water before hitting the gym hard.

You can learn how the body responds to your workout’s intensity with the help of Continuous temperature tracker equipment. It monitors your core body temperature continuously to see how it fluctuates to a set point. 

Keeping a close eye on your core temperature as you work out might assist you in effectively modifying your routine to match your fitness level.

5. Stress

The human body raises its temperature in response to stress. Adrenaline and cortisol, two stress hormones, mediate this rise in core body temperature. The body’s adaptive response to stressors causes a temperature rise. 

The hormone adrenaline, which controls the human body’s “flight or fight” reaction, triggers several adaptive responses, including increased heat generation by the liver. The liver significantly affects core body temperature because it is huge and metabolically active.

6. Meals

The average person’s core temperature rises just a bit after eating. Twenty to thirty minutes following eating, you may feel a slight rise in body temperature, detectable with a continuous temperature tracking device. Your rate of metabolism has increased to help you digest your food.

7. Smoking and Other Drugs

Methyldopa, phenytoin, and various antibiotics (penicillins, cephalosporins, etc.) are some of the pharmacological medications that raise core body temperature. Body temperature also rises when people consume recreational drugs like cocaine and MDMA.

8. Location of the Temperature Tests

Where you take someone’s temperature can affect the accuracy of their reading. Below are some ground rules for determining why temperature readings can differ amongst the most popular places to take them. 

An internal temperature reading is often higher than most oral readings by 0.3°Celcius to 0.6 °Celcius [0.5 to 1°Farenheit], whereas an underarm temperature reading is typically lower by 0.3°Celcius to 0.6 °Celcius [0.5° to 1°Farenheit].

An invasive procedure is the only reliable way to determine an individual’s core temperature. Despite their precision and reliability, intrusive techniques are often inappropriate. 

There has long been a consensus that rectal readings are reliable and convenient. However, rectal temperature measurement has fallen out of favour recently due to patient resilience, reluctance, and fears that it promotes the spread of illnesses.

How The Body’s Temperature Affects One’s Sleep

Your capacity to regulate your body temperature significantly impacts how well you sleep. 

Winding down for the night is a form of thermoregulatory behaviour. Your core body temperature drops as your circadian cycle prepares you for sleep. 

Mammals engage in behavioural thermoregulation in response to temperature drops, which include activities like seeking warmth, nest-building, and curling up. 

When you enter NREM, your brain and body temperature drop, but when you enter REM sleep, they rise again.

Simply put your body’s ability to regulate its temperature before bed directly relates to the quality of your sleep throughout the night. Some medical problems, however, can interfere with your body’s natural temperature control mechanisms.


Symptoms of menopause can manifest in different ways for different women, but most of the more common ones are known to disrupt a woman’s ability to get a good night’s rest. Night sweats and hot flashes are two of the more well-known symptoms of menopause.

A woman’s chest, neck and head may suddenly feel hot during a flash. Hot flashes during sleep are known as night sweats. 

It is normal for women going through menopause to experience nighttime awakenings due to feelings of heat and sweat. Hormonal imbalances are to blame for these symptoms, which can persist for up to seven years.

So, why is it important to regulate body temperature? When a woman’s hormone levels fluctuate, she may experience hot flashes, which are severe attempts to cool down after experiencing even a slight increase in the woman’s core temperature. 

Hormone replacement therapy is the gold standard for managing menopausal hot flashes, but there are other, less invasive ways to alleviate the problem and get a good night’s rest. (I’ll elaborate)

You may also be interested in our latest article, Menopause and Sleep Disorders through a Gender-Specific Look. 

Sleep Loss

Some of the impacts of lack of sleep on the body may be a complete surprise. Hormonal disruption is one of the possible outcomes. Lack of sleep can cause hormonal abnormalities, which, like menopause, can elevate your body’s core temperature and make sleeping unpleasant.

The hypothalamus, which also controls body temperature, interacts with the pituitary gland to regulate hormone levels. 

The efficiency with which your hormones work determines how the body reacts to its surroundings, and hormone efficiency is, in turn, influenced by the quality of your sleep. 

Because your body needs sleep for proper functioning, and functioning on little sleep can lead to a wide range of negative consequences, you should undergo testing if you suspect a sleep issue.

Obstructive Sleep Apneas (OSA)

The connection between thermoregulation and OSA is fascinating. Symptoms such as choking, gasping in sleep and loud snoring while sleeping are hallmarks of sleep apnea, which happens if the airway becomes partially or fully blocked during sleep.

Sleep apnea issues result in insomnia and sleep deprivation, which negatively affect the body’s ability to regulate temperature, such as the hormonal imbalances discussed above.

Among the many mechanisms your body uses to maintain a steady internal temperature, sleep apnea shares an interesting similarity with thermoregulation. Reflex bronchoconstriction causes the airways to narrow when exposed to chill or cold air, delaying the delivery of uncomfortably cool air to the lungs. 

Due to the nighttime drop in temperature, sleep apnea may serve as the body’s natural mechanism for maintaining an adequate core body temperature.

Still, sleep apnea can be a life-threatening disorder leading to various other health issues. Seek prompt medical attention if a loved one or yourself suspects you or they suffer from sleep apnea.

Why Do Certain Individuals Get So Hot When Sleeping?

Many people assert that they sleep hot, yet the term has varying and sometimes conflicting meanings depending on who you ask. 

Some folks are out here attempting to sleep in accommodation on a sixth floor with no ventilation, air conditioning, or cooling in the summertime, while others are worrying about more inexplicable things. It’s not that neither of those things could happen; it’s just that some issues have more straightforward solutions.

Others can’t stand the sight of covers and spend several hundred dollars in power due to the immense number of fans aimed towards their beds all night because they can’t stand waking up sweaty. 

We aren’t going to urge you to buck up whether you are experiencing symptoms of a hot flash or you tend to become overheated when sleeping. 

We now know that a higher body temperature increases sleep inclination or the ease of falling asleep. On occasion, though, this coping technique is a little greater than a happy accident.

For instance, a new study published in the journal Current Biology found that the brain’s temperature drops with the commencement of NREM sleep. The external or surrounding environment mainly governs the brain’s temperature throughout the REM sleep cycle.

This fact implies that if you are in the REM phase of your sleep and your bedroom gets too hot, your body will wake you to regulate your temperature. 

Going to sleep late or consuming alcohol can cause a more extended period in REM phases, leading to more frequent awakenings and a decline in the body’s ability to regulate temperature while you sleep.

Another study from the University College of Leeds found that jet lag, sleep deprivation, and residing in permanently gloomy environments can all throw off your body’s natural 24-hour clock. 

Over time, these disturbances might reduce your body’s ability to self-regulate its temperature, making it harder to sleep. 

This means that a lack of sleep one night may make it more difficult to fall asleep the next and that once you do fall asleep, you may wake up feeling warmer and less refreshed than usual.

People who are more physically active or accustomed to warm locations may start sweating at cooler temperatures compared to others, even if their circadian rhythm is working normally, according to research from Harvard. 

If you are trying to keep cool while working out, this is wonderful news, but if you have a habit of waking up sweaty and dumped, it could be your worst nightmare.

People who are not as physically active may not feel as cool as they should. Even though their circadian rhythms are on point, they’re actively attempting to cool down when they should be more relaxed.

Wearing socks to bed may prevent the body’s natural cooling process from releasing excess heat via the skin, according to research from Pennsylvania State University. 

Unless a barrier prevents the heat released through the skin from escaping, heat transmission should not disrupt sleep, even if it makes us feel warmer on the skin’s surface. 

Even if your body temperature is average when you sleep, you may still feel hot due to poor ventilation, tight clothes, socks or humidity. 

Furthermore, the Manual of the Biological Impacts of Electromagnetic Forces suggests that your body’s capacity to cool directly relates to your general body mass, food, and hormone levels rather than the climate in which you reside. 

You can investigate other behavioural or internal variables leading to hotter sleep rather than blaming the Arizona heat or the country’s winter.

Why Do Certain Individuals Get So Cold When Sleeping?

The decrease in thermoregulation during rapid eye movement periods can cause a person to feel cold if their environment is cooler than their body temperature, just as it does for warm sleepers. 

During the rapid eye movement (REM) cycle, you might wake up excessively cold if you sleep with your window open and no blankets, mainly if you spend a more extended period in rapid eye movement than non-rapid eye movement because of alcohol or other circumstances. 

Due to age-related reduced heart functions and declines in vascular volume, older people may be more prone to nighttime chills.

Cooler temperatures are preferable for sleep, mainly if you are covered warmly enough, so sleeping chilly won’t wake you as often as in hot conditions. 

Monitor your core temperatures to ensure you don’t experience fevers, or visit a doctor to find out what else could be hurting your capacity for regulating your body’s internal temperatures if you’re constantly cold, even when wrapped in blankets.

Some circulatory problems can interfere with the body’s natural ability to control temperature using vasoconstriction and vasodilation. On the other hand, if you ate a lot that day, you might feel chilly at night. 

Given the metabolic demands of digestion, this could cause the circulation to the skin to decrease. If your hands and feet are always chilly when you sleep, try dining earlier or consult a physician about safe ways to increase your circulation.

The Effects of Lack of Sleep on Energy Efficiency

Rapid temperature changes, sweating, and a warm body can all devastate how well you sleep. Therefore, thermoregulation is not only about comfort; you may suffer from sleep deprivation if it isn’t working properly. Sleep deprivation, unfortunately, has more severe repercussions than merely tiredness and dark circles under your eyes. 

Based n reports from the American Psychological Society, getting enough sleep can make it easier to sweat during moderate exercise the following day. 

Because of this, you may feel exhausted during exercise the next day and have trouble regulating your body temperature, which can decrease athletic performance, stamina and energy. 

The body restores its immune system, heals itself and stores energy throughout the non-rapid eye movement (NREM) and rapid eye movement (REM) stages of sleep. 

Inadequate access to these processes can negatively affect a person’s mental health, energy levels, emotional regulation, and physical development.

Utilising Thermoregulation to Help You to Get a Good Night’s Rest

The good thing is that there are several tried-and-true methods for getting your thermoregulation in sync and using it to enhance your sleep and, by extension, bodily function during the day. 

According to research published in a journal, “Behaviour and Psychology”, warming one’s skin to a temperature it typically reaches just before sleep may boost your sleep tendency (or capacity to shift from wakefulness to sleep). 

As the study shows, the reason is that it tricks the body into cooling itself by constricting blood vessels to counteract the simulated vasodilation’s warming effects. It’s counterintuitive, but if you have been overheating, you can cool down by doing the opposite of what you may normally do.

Time Your Workouts

If you time your workout such that it ends just before bed, your body will have time to adapt by increasing vasodilation, releasing heat, and cooling you down before bed. 

Experts in Neurology released a study that found that going for a quick jog or walk approximately one hour before bed can help sync your thermal regulation temperature and bring you to sleep in no time. However, we wouldn’t advocate doing so shortly before you go to bed because it might keep you awake longer.

However, some research has shown that blood pressure might start rising a couple of hours before waking up, so there might be better options for some with cardiovascular or cardiac problems. Talk to a physician about your limitations if you’re worried.

Change Your Pre-Bedtime Snack Routine

All of the blood in the body will rush to the stomach to help with digestion, so don’t be shocked when you start warming up or even wake to chilled feet and hands and if you eat a large, carbohydrate-heavy, fatty meal right before bed.

Eating something light, high in protein, and easily digestible is best when hunger strikes in the wee hours. Those of you who are lactose intolerant but have a severe cheese addiction, we see you.

You May Need to Tweak Your Bedroom’s Temperature

Body temperature during rapid eye movement (REM) sleep depends mainly on environmental conditions. 

Keeping your bedroom chilly (between 60 and 72 degrees Fahrenheit for people) might aid in falling asleep more quickly and boost the duration and quality of your rapid eye movement (REM) sleep, all beneficial to your health.

Use Breathable Sheets and Pajamas

Cotton pyjamas that allow air to circulate will keep your body dry and comfortable when the temperature rises and won’t prevent your skin from cooling down. You might consider sleeping naked if you dare to do so. Nude sleep may be the best option if you can’t control the heat.

Hot Baths or Pre-sleep Soak in a Steamy Tub

One study from Loughborough University found that bathing in warm or hot water before bed (but not right before) aided in both falling asleep and maintaining a restful slumber. 

Many researchers have found this trustworthy and have coined the term “Warm or Hot Bath Effect” to describe it. 

However, lest you become too excited, you should know that a hot or warm shower won’t be as good at elevating your core body temperatures because only a small body surface area is exposed. 

If you soak in a hot or warm bubble bath (the bubbles provide insulation) for approximately ten minutes, your body temperature should rise to around 100 degrees Fahrenheit and then gradually decrease as your body cools down.

Change Your Bed, Bedding or Mattress

Most contemporary mattresses include a conditioning bed system. However, not all of these features are of similar quality. 

Copper-infused gels and convoluted foams are two additional features that improve airflow on sprung hybrid mattresses. Bedding is another item to think about after a quality mattress.

Cotton and other breathable fabrics help keep the air moving, soak in moisture, and keep you from being too hot in places you do not want to be. 

However, before you throw out your warm blankets, remember that you will likely want a warmer and more pleasant bed while you figure out how to regulate your body’s temperature.


Uncomfortable heat is among the most common sleep disturbances, but it does not have become the most difficult to remedy. 

You may have noticed that sleeping and maintaining your slumber is more challenging because of your bedroom’s high temperature. 

Your body may not be able to control its internal temperatures by itself. Still, with some new habits and tools, you may experience less heat-related insomnia and enjoy better sleep overall.

We recognise that your experience may be more complicated than average, but we hope this data will help you take the next step toward a more positive one.

Share this Post

You may also like

sleep number alternative bed

The 5 Best Alternatives To A Sleep Number Bed in 2024

A $2,899+ price tag for a Sleep Number Bed can be a little too expensive

Read More>>

Koala Soul Mate Mattress Review (2024)

Looking to enhance your sleep quality? Look no further. Koala’s Soul Mate mattress may be

Read More>>

Koala Calm As Mattress Review (2024)

In a world where the hustle never stops, the ability to embrace a good night’s

Read More>>
exclusive deals

Huge savings on Australia's best mattresses!