Home / Blog February 17, 2023

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9 Possible Reasons That Explain Why You Sweat In Your Sleep

Sweating in your sleep can have many root causes depending on your age and condition. Physical issues like hormone imbalances or illness often play a role, as do mental health and environment factors. Determining the cause may involve going over a list of possibilities with a healthcare worker.

Why do I sweat in my sleep


If you’re sweating during sleep, the first thing to rule out is a hot bedroom and bedding.

Some medical conditions like menopause, infections, and cancer treatment can also cause night sweats.

Side effects from medications and even stresses on the body from mental health issues are also known to trigger nighttime sweating. 

Did you know?
A harmless condition called hyperhidrosis can lead to excessive sweating, especially in areas like the armpits, palms, and feet.

The causes of night sweats are varied and individual. One study found that they affected 34% of primary care patients, with age being a minimal factor. It’s different for everyone, so with that in mind, here are 9 possible reasons that explain why you sweat in your sleep.

1. Sleep Environment

The term night sweats is often tossed around casually, leading some to think that it simply means “sweating at night.” However, a more clinical definition suggests that night sweats involve sweating despite an otherwise temperature-appropriate sleeping environment.

What exactly does that mean? Well, as we get ready to wind down toward a snooze, our core temperatures drop. And our sensitivity to heat changes throughout the phases of sleep, too.

During the deeper stages of sleep (non-REM), we grow more susceptible to overheating. In other words, if conditions are a little on the warm side as you’re drifting off, they may feel too hot later on.

To combat this, try to set up for success when you hit the sack. Here are just a few factors to consider:

  • Room temperature. 60-67 degree Fahrenheit is the average optimal temperature range for human sleep, though this depends on the person.
  • Sharing a bed. If your bed partner runs hot, it could be cranking up your temperature, too. This may even apply to sleeping with dogs.
  • Nightwear. Do you sleep in tight-fitting flannel? If you’re waking up sweaty, it might be time to stop.
  • Bedding. Just like heavy PJs can make you hot, so can the material of your bedding. You may want to consider making the change to cooling materials like TENCEL, which our cooling weighted blanket uses. 

If you’ve ruled out the above, it’s time to look at other sources of trouble.

menopause - Why do I sweat in my sleep

2. Menopause

While a hot room might be a little easier to work around, a body that overheats no matter what throws up a different type of road block. That’s the challenge many in mid-life are facing as they go through menopause-related hormone changes.

These changes come at different times and intensities depending on the person, but for the most part women start to experience it in their 40s. There are also three distinct phases of menopause leading to different levels of hot flashes:

  • Perimenopause: The beginning phase where estrogen levels start to decrease. Can last 10 years, with 85% of women seeing hot flashes at this time.
  • Menopause: Doctors will diagnose menopause after 12 consecutive months of no menstruation. During the transition from perimenopause, the number of women experiencing hot flashes decreases to an average of 55%.
  • Post-menopause: The phase after menopause has been declared. At this point, only 25% of women continue to experience hot flashes. 

A previous article outlined ideas for menopause remedies that may help. Some of the methods include diet and lifestyle changes while others involve simple adjustments to nightly routines.

3. Hormone Disorders

While menopause is one of the most common conditions that affects hormone levels, it’s not the only one. There are several others out there that can lead to similar hot flashes and sweating in bed.

These hormone disorders are a product of problems with the endocrine system, a delicate balance of glands that produce hormones which are then released into the bloodstream. When that balance is thrown off, it can lead to several problems, some of which may explain why you’re sweating in your sleep. Here are a few examples:

  • Hyperthyroidism
  • Diabetes
  • Endocrine tumors 

Each condition has its list of potential treatments which should be discussed with a healthcare professional.

Autoimmune Disorders - why do i sweat in my sleep

4. Autoimmune Disorders

Sometimes, night sweats are the body’s way of compensating for changes to hormone levels. And sometimes they can be related to deeper issues within the immune system, known as autoimmune disorders

There are many different types of these disorders that affect the immune system, but they all share the trait of mistakenly attacking healthy areas of the body. Here are a few examples:

  • Celiac disease
  • Rheumatoid arthritis
  • Type 1 diabetes 

If you have such an autoimune disorder, your immune system may get confused and throw up its defenses when there’s nothing attacking the body. Often, this means fever-conditions and sweating in bed.

Some of the other symptoms of autoimmune disorders include fatigue, skin problems, and joint pain.

5. Infections

In most cases, running a fever is actually a good thing, showing that the body is doing its job. A common example of this is when it’s fighting off infection.

Those infections can come from many places, but one of the more common routes of entry is through the respiratory tract. Breathe in a bacteria, give it a home in your lungs, and eventually a healthy immune system will work to burn it away. Unfortunately this often means coming down with a fever.

Most of these infections pass after one or two weeks, but sometimes the more serious ones like tuberculosis can last longer. This one area where weighted blankets can be of service as they help to boost the immune system.

However, if you notice your fever episodes lasting for longer than a week or two, it may be time to see a doctor for treatment.

6. Cancer Treatment

One last possible medical issue that could be triggering night sweats is cancer treatment.

In the battle with cancer, patients often undergo aggressive procedures like surgery. One of the more common ones for men involves removal of the testes which can cause a testosterone imbalance, leading to hot flashes.

In women, doctors may remove the ovaries depending on the type and stage of cancer. This, along with radiation therapy can sometimes put women into early menopause, leading to similar hot flash symptoms.

To treat these, doctors may offer hormone replacement therapy or other remedies to bring hormone levels up. Though many of these treatment options come with other risks.

7. Alcohol and Other Substances

While doctors may prescribe certain medicines to keep hot flashes under control, other types may be the source of those episodes.

Here are a few types of medicine that may lead to excess sweating:

  • Antidepressants
  • Opioids
  • Diabetes medications
  • Corticosteroids like prednisone 

Medications aren’t the only substances you can put in your body that leads to sweating, though. Caffeine, for example, has been known to lead to excess sweating in some.

Another is alcohol. It acts as a vasodilator, meaning that if too much is ingested (enough to get tipsy), the skin can start to flush, leading to sweating in some people.

Because of that, taking inventory of the substances you put in your body may be an important step in cooling down at night.

8. Sleep Apnea

If you’ve ruled out everything else on this list, it may be time to take a look at other sleep issues. In particular, obstructive sleep apnea (OSA).

Having this condition means that the soft tissues in the palate and throat area block the airway during sleep. This temporarily stops breathing, causing stress on the body. As if losing the ability to breathe wasn’t bad enough, that stress can also lead to night sweats.

One Icelandic study from 2013 following 800 patients of different backgrounds found that 33% of OSA patients had frequent night sweats (three times a week or more). The good news is that the same study also found that use of a CPAP machine brought that number down to 11.5%.

Add this to the list of benefits a CPAP machine for sleep apnea can provide.

9. Stress And Mental Health Problems

While sleep apnea causes a lot of stress on the body, sometimes that stress comes from within. Specifically, mental health disorders.

A 2004 study published in the Annals of Family Medicine monitored a large group of elderly male and female patients, searching for possible links to night sweats, day sweats, and hot flashes. It found that those who had issues with all three were more than twice as likely to show signs of depression or anxiety.

The reason for this connection may have to do with the body’s stress-response system, which releases hormones like cortisol during heightened states.

Because of this relationship, finding ways to lower stress and anxiety levels can lead to improved symptoms. And one tool that can help with that is weighted blankets like our knitted weighted blanket.

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The extra weight provides a grounding effect that can generate a calming sensation from the heightened serotonin and lowered cortisol levels. As an added bonus, it may also help get you snoozing.


There may be many possible reasons why you sweat in your sleep, ranging from medical problems like hormone disorders to simpler explanations like hot bedding. Assessing the reasons and possibly consulting a health professional for treatments could help get those night sweats under control.