If your bedroom is too hot or too cold, you’ll probably have trouble getting to sleep. The optimum room temperature for sleep is around 19 to 21°C. Even if your bedroom is the perfect temperature for you, it’s still possible to get too hot at night. Your bedding, your pre-sleep routine, certain medications, and certain medical conditions can all make you feel too hot.
Here are seven reasons why you may feel hot while sleeping.
1. Chamber temperature and humidity
If you are too hot at night, it may be because the temperature in your room is too high. Exposure to heat at night increases wakefulness and decreases slow wave sleep and rapid eye movement sleep. Humidity can also amplify the effect of heat by reducing your sweat’s ability to evaporate.
2. Bedding and sleepwear
Your bedding acts as an insulator, just like the insulation in your home. Thick bedding tends to retain more heat than thinner bedding, and wearing heavy sleepwear can also lead to overheating. Different fabrics have different heat retention properties and can influence the quality of your sleep. A small 2016 study compared the effects of cotton and wool sleepwear and polyester and wool bedding on sleep quality at temperatures of 17°C and 22°C. Researchers found that wool sleepwear promoted sleep onset more than cotton at 17°C, but cotton promoted deeper sleep at 22°C. The researchers found no difference between polyester and wool bedding in the onset or quality of sleep, regardless of temperature.
3. Activities before bedtime
Activities you do before bed can potentially raise your body temperature and make it harder to fall asleep.
– Exercise. Evening exercise had no negative impact on sleep and actually had the opposite effect. But the onset of sleep may be impaired if vigorous exercise ends within an hour of bedtime.
– Caffeine. It’s well documented that consuming caffeine close to bedtime can make it difficult to fall asleep. In addition to increasing mental alertness, caffeine is associated with higher core body temperature.
– Stressful activities. When you feel stressed, your blood vessels constrict. This action lowers your skin temperature and raises your core body temperature.
– Sex. Sex can improve sleep quality by releasing hormones that promote relaxation. However, vigorous sex that increases your heart rate can have the same effect as exercise.
4. Who sleeps with you
If you sleep with other people or pets, the combined temperature of your bodies can increase the temperature under your bedding and in your bedroom. Bodies constantly give off heat as a byproduct of metabolism. The more bodies and the smaller the space, the faster the area heats up. The average temperature of a human body is around 37°C. If the room temperature is above this value, your body will absorb the heat and have a cooling effect on the room.
5. Drug medications
A long list of medications can potentially raise your body temperature or disrupt your body’s ability to regulate its temperature.
Commonly used drugs that affect thermoregulation include
– anticholinergics
– beta-lactam antibiotics, including penicillin and cephalosporins
– carbamazepine
– medicines for diabetes
– diuretics, especially combined with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers
– hormone therapy drugs
– methyldopa
– analgesics
– phenytoin
– procainamide
– psychotropics
– quinidine
– SSRI or tricyclic antidepressants
– steroids such as cortisone or prednisone
– drugs such as MDMA, ecstasy, cocaine
6. Hormones
Hormonal imbalances can lead to night sweats or hot flashes. Many women experience night sweats as part of PMS, due to fluctuations in estrogen and progesterone levels. Night sweats and hot flashes are two of the most common symptoms of menopause. Reduced estrogen levels and other hormonal changes that are not fully understood are thought to cause these symptoms. Pregnancy also causes hormonal changes that increase blood flow and core body temperature. Hyperthyroidism and obstructive sleep apnea (which can affect various hormones) are two other potential causes of feeling hot and sweaty at night.
7. Illness and infection
Many potential illnesses can lead to an increase in body temperature or cause night sweats. Infectious diseases that can cause a rise in body temperature are:
– influenza
– angina
– pneumonia
– tuberculosis
– other bacterial infections
– a cold
Other conditions can cause you to feel hot at night:
– the cancer
– coronary heart disease
– hyperhidrosis
– hyperthyroidism
– chronic stress
How Body Temperature Affects Sleep
Your body temperature follows a natural cycle over a 24-hour period. Normally, your body temperature
– drops in the evening
– increases in the morning
– peaks later in the day.
If your body temperature does not drop at night, it can negatively impact your sleep.
Solutions to feeling overheated at night
Here are some solutions to stop feeling overheated at night.
– Ambient temperature too high
– Turn down your heating.
-Open a window.
-Use a dehumidifier.
-Use a fan
-Move your mattress towards the floor.
-Take a cold shower before going to bed.
Bedding
-Use fewer blankets.
-Choose light and breathable fabrics.
Pre-sleep activities
-Finish exercising at least an hour before bedtime.
-Avoid consuming caffeine in the late afternoon or evening.
-Minimize stressful activities as bedtime approaches.
-Avoid vigorous intercourse before bedtime (non-vigorous intercourse can improve sleep quality).
Sleeping with other people or pets
-If you sleep with other people, consider using a separate blanket.
– Consider opening a window or leaving the door open.
Medications
-Contact your doctor and see if you can adjust your medications.
Hormonal conditions
-Ask your doctor about the best treatment options for your particular case.
Illness or infection
Try to treat the underlying condition.
