Air conditioning can improve sleep on hot nights, as long as you use it in moderation: a cool room, not a cold one, and with the air not blowing on you. Cold air for many hours may dry you out and cause discomfort.
Below you can see which temperature helps, what benefits and risks an air conditioner has at night, and how to set it.
Why temperature matters for sleep
The body follows a natural biological clock, the circadian rhythm, which is affected by light, temperature and other factors. During the night body temperature drops slightly, and this helps you get sleepy and sleep deeply.
Many sources give about 16 to 20 °C as the ideal room temperature for sleep. In a warmer environment the body finds it harder to cool down, and in the cold sleep may be interrupted. If you sleep hot, you may wake more often and feel more tired in the morning. These are rough guides, everyone has their own preferences. Humidity plays a part too: hot, humid air makes the night harder, and here an air conditioner can help.
What air conditioning can offer
- A steady temperature all night.
- Less sweating and discomfort.
- Easier sleep in areas with a lot of humidity.
When you are not too warm, the body reaches the temperature it needs for deep sleep more easily, and you wake less from heat or sweat. To stop the air conditioner running strongly all night, cool the room smartly: close the shutters in the morning, open the windows when it cools down in the evening and let the air conditioner run for a while before you go to sleep.
What to watch for
Cool air is pleasant, but if the air conditioner runs strongly all night it may cause:
- dryness in the throat, nose and eyes,
- muscle stiffness, especially if the air blows directly on the body,
- interrupted sleep, if the temperature is too low,
- trouble with allergies or breathing, if the filters are not cleaned.
Be especially careful if babies, young children, elderly people or people with breathing problems sleep in the room: strong cold air often bothers them more. If you have questions, ask your doctor.
Practical tips
- Set the thermostat at around 23–25 °C, not much lower: in summer 16–20 °C is often neither realistic nor comfortable.
- Use a timer, so that it switches off after 1–2 hours.
- Clean the filters regularly.
- Place the unit so that it does not blow directly onto the bed.
- Combine the air conditioner with a ceiling fan, for better air circulation.
- Do not aim the air at yourself, so that your throat and eyes do not dry out.
If you do not have an air conditioner or do not want to run it all night, a fan and open windows when it cools down in the evening are often enough for most nights. What matters is not to sleep in strong heat or in the cold.
If you wake up with stiffness in the neck or back, see where the air blows and whether you need to move the unit or the bed. If the air conditioner wakes you when it switches off, check whether your device has a sleep mode, which raises the temperature gradually. And if one of you gets hot and the other cold, a shared moderate setting and separate bedding help.
Coolness in your bed too
Coolness does not depend only on the air conditioner. Light sheets of cotton or linen, a light blanket instead of a heavy duvet and light pyjamas help you avoid overheating. A mattress protector that breathes protects the mattress from sweat, and it is worth airing the mattress when you change the sheets. ORION mattresses use, among other materials, foams, latex, Memory Gel and Coolmax fabrics, which help to draw moisture away.
A lukewarm shower before bed, water during the day, and less alcohol and heavy food in the evening also help. If you get very hot at night or sweat heavily and often, talk to a doctor.
In short
A cool room, a steady temperature and clean filters, without the air blowing on you, are the basics of good summer sleep. Browse the mattresses or ask Sleep Match, which asks how you sleep and what you like and suggests mattresses.
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