How to Sleep In Hot Weather (Or When You Feel Overheated)

A hot, humid night can make it difficult to sleep. Hot flashes also create havoc with sleep. And if you have obstructive sleep apnoea, the pauses in breathing that occur every night can further disrupt sleep once you’ve managed to drift off. You can take several steps to cool down in the evening and stay comfortable through the night. 

How Does Temperature Affect Sleep?

In a normal sleep cycle, the body temperature decreases in the early evening -- part of your circadian rhythm, which also regulates sleep, appetite, mood, and other functions. 

During the day, your eyes perceive natural light and send a signal to your brain that you should be awake. This stimulates the production of the hormone cortisol, which makes you feel alert and keeps your body temperature at a normal level -- around 98.6. 

After sunset, your eyes perceive darkness and signal your brain. This triggers the release of melatonin, the hormone that induces feelings of tiredness and relaxation -- which causes your body temperature to dip.

At bedtime, your body temperature will further decrease during the first stage of sleep --  non-rapid eye movement (NREM) stage. Before you wake up, your body temperature will gradually return to its normal level -- to help you feel fresh and alert. 

External temperatures can interfere with this natural regulation. If your bedroom is too warm, this increases your body temperature and disturbs your sleep. Restorative physiological processes will be interrupted, so you won’t feel well-rested in the morning.

How to Stay Cool On Hot Nights

You may need to take extra precautions for keeping cool when it’s too hot to sleep. 

Tips for optimising your bedroom for cool, comfortable sleep:

  • Close the curtains: Your bedroom will stay cooler during the day if you keep sunlight out. Many people find blackout curtains, which are designed to block all outside light, are particularly effective at keeping bedrooms cool in the summer and insulating against the cold when temperatures drop.
  • Don’t exercise at night: While exercise during the day can help promote sleep, helping you feel more tired, exercise close to bedtime causes an increase in body temperature -- which makes falling asleep more difficult. 
  • Take a hot bath: You might be surprised this can actually help you cool down at bedtime. Your body temperature will decrease after you leave the bath as your body adapts to the cooler environment. Baths promote feelings of relaxation to help you fall asleep more quickly.
  • Invest in the right mattress and pillow: Mattresses made with thick foams tend to absorb and trap body heat. Other mattresses are cooler due to ventilated latex and open coil systems that circulate air throughout the interior. Certain pillows can be heat traps, but other types – such as latex, ventilated foam, and wool – provide above-average temperature control.
  • Buy natural bedding: Cotton and linen sheets and pillowcases offer better breathability than those made from polyester and other synthetic fabrics. Bamboo fabrics can also provide adequate cooling.

More cooling measures to take: 

  • Set your thermostat to 65 degrees: Experts agree that 65 degrees Fahrenheit (18.3 degrees Celsius) is best for sleep. This setting helps your body maintain its natural core temperature for sleeping. 
  • Use a bedside fan: A fan will circulate air through your room to help you stay cool. Even if you already use an air conditioner, consider a fan for added airflow.
  • Keep water close: A cool glass of water on your nightstand can provide much-needed relief if you wake up due to excessive heat. An ice pack will also work in a pinch.
  • Freeze your pillowcases: For extra cooling when you go to sleep, place your pillowcase in the freezer in the evening and put it on your pillow before getting into bed.

Try to develop a good bedtime ritual to help your body relax and unwind. This means avoiding using screens and devices before trying to sleep. Make sure that your bedroom is a quiet, dark sanctuary that supports a peaceful night's sleep.

If you are experiencing daytime drowsiness, poor sleep or your partner notices your snoring, or breathing stoppages during the night, see your GP. It’s important to speak with a doctor who can start to diagnose what is causing the sleep disruption -- as it could be obstructive sleep apnoea. 

In fact, menopausal women are at higher risk of sleep apnoea. Research suggests lower progesterone levels, like those observed in postmenopausal women, may contribute to the development of sleep apnea. 

Obstructive sleep apnoea can be treated effectively so that you can maintain your quality of life and get the restorative sleep your body needs to stay healthy.

To learn more about how sleep apnoea and for more information about treatment, follow the links below. 


Somnowell Inventor - Visiting Professor Simon Ash FDS MSc MOrth BDS

Prof. Ash is the inventor of the highly successful SOMNOWELL Chrome device for snoring and sleep apnoea.

The Somnowell Chrome is made to exacting standards in the Somnowell laboratory under the supervision of Visiting Professor Simon Ash. Prof. Ash and his master technicians create each Somnowell Chrome device using their wealth of experience and expertise.

Prof. Ash works at the forefront of his profession. He is a Consultant and Specialist Orthodontist with over 30 years clinical experience, with a special interest in sleep related breathing disorders, TMJD, and bruxism. He currently works in Harley Street London and two private hospitals in London as part of a multi-disciplinary team managing snoring and sleep apnoea, and is Visiting Professor of Orthodontics at the BPP University.