Body temperature and sleep

Short answer: To fall asleep, your body temperature needs to drop by around half a degree. Anything that prevents that drop makes it harder to fall asleep. Thin clothing, a cool bedroom and warm feet all help the body along.

The drop is the signal for sleep

The body uses the drop in temperature as a signal that it is time to sleep. In the evening, temperature starts to fall slowly, and once it reaches a certain level, falling asleep becomes easier. It is part of your daily rhythm and happens on its own. Your job is simply not to get in its way.

Clothes that are too warm block the drop

If you are dressed too warmly, the body cannot release enough heat. The temperature stays up, and sleep keeps you waiting. Many people put on a thick jumper in bed because they feel cold when they lie down. But a thick layer can hold so much heat that you wake up sweaty later. A thinner layer is often the better choice.

Thin and moisture absorbing

The best thing to sleep in is something thin that absorbs moisture. At night the body releases moisture, and a fabric that can absorb it helps the skin stay dry. A loose T-shirt in a soft fabric is a simple choice for many. See our bamboo T-shirts for women if you want something light to sleep in.

Underwear that does not squeeze

Underwear plays a part too. Tight waistbands can be bothersome when you lie down for many hours, and they can trap heat close to the body. Choose something soft that fits close without squeezing. Have a look at our bamboo underwear for women if you want something that feels light at night.

The feet control most of it

Warm feet help the drop, cold feet prevent it. When your feet are warm, the blood vessels widen and the body can release heat through them. When your feet are cold, the body holds on to heat instead. That is why a pair of thin socks can make it easier to fall asleep. See our bamboo socks for men and women.

A cool bedroom

The bedroom matters as much as the clothing. A cool room makes it easier for the body to release heat. Air the room before you go to bed, and avoid turning the heating up too high in the evening. Then you can have a good duvet and thin clothing and still lie comfortably all night.

Too cold wakes you later

The opposite is true as well. If you are dressed too lightly, you may fall asleep but wake later in the night because you are cold. Body temperature keeps falling during the night, and then a layer that is too thin may not be enough. Find the balance that suits you and your bedroom, and adjust it with the seasons.

Small evening habits

Many find that a warm bath a while before bedtime helps, because the body releases heat and cools down afterwards. A heavy meal just before bed can have the opposite effect, as digestion produces heat. If you struggle to sleep over a longer period, talk to your doctor about it. Clothing and habits can help, but they do not solve everything.

Frequently asked questions

Why does the body need to cool down to sleep

Because the drop in temperature is the signal the body uses to start sleep. Without the drop, sleep comes more slowly, and it can take longer to settle.

What is the right thing to wear in bed

Something thin that absorbs moisture. Clothing that is too warm blocks the temperature drop, and too little wakes you later in the night as the body cools further.

Why do warm feet help with sleep

Because warm feet make the blood vessels widen, which lets the body release heat and cool down. Cold feet, on the other hand, hold on to the heat.