Heat death in your sleep? 12 power tips for a good night's sleep in the heat.

Schlafen bei Hitze in der Dominikanischen Republik

These are the temperatures here in Sanchez (Dominican Republic) in week 26/27, but they have been the same for the last 2 months that we have been here. And they will continue to be in the coming months. Incidentally, the rain is always brief.

Unlike in Germany, heat is the permanent norm here and people have adapted to it … also in terms of sleep. Even if air conditioning is normal in houses of a somewhat higher standard, this is by no means the norm here.

What do you need to know about sleeping in the heat to avoid spending the night sleepless in a sweat? The following 12 tips will help you!

1. knowledge of the body's reaction.

First of all, it is generally important to know and support the body’s natural reaction to heat. The body tries to regulate body temperature on its own. Further measures should support this, not counteract or undermine it.

Sweat is used for cooling, for example, so sweating itself should not be suppressed by creams or even surgery. In return, it is also important to know that the body reacts very quickly to cold with an opposite reaction. In other words, if we react to heat with too much cold, the body reacts by producing heat. And that is exactly what is counterproductive in the heat.

Can the body get used to heat? Yes and no. The perception of heat can be greatly reduced the less physically we suffer from it. However, this should not tempt you to go beyond your own limits.

So don’t react with cold without moderation, but support the body intelligently. More on this in a moment.

2. heat-dissipating clothing

A good bedroom temperature is 18 degrees. This does not necessarily apply to summer. If this room temperature cannot/should not be reached, then reduce elements that bind the heat in your body, such as your clothing. Wear light pajamas made of natural fibers that release heat well.

More on this in the study linked here.

Oh yes … There are recommendations to put your sleepwear in the freezer before putting it on. I expressly do not recommend this. The reason is the same as the one against cold showers. More on this in the following recommendation.

3. lukewarm showers

Cold showers are certainly the more pleasant option, but are generally counterproductive, especially before going to bed, as already mentioned in point 1. As a natural reaction, cold showers cause the blood vessels to contract, which leads to heat build-up in order to keep the heat in the body when the cold threatens. This is a natural reaction, as the body tries to prevent itself from cooling down too much when it is extremely cold. He doesn’t know what we use it for and for how long. It is therefore better to take alukewarm shower, as there is no counter-reaction from the body.

At the same time, the cold shower interrupts the onset of the sleep process, as this is accompanied by the dilation of the blood vessels to release heat and cool the body down for the night. The contraction of the blood vessels therefore has the complete opposite effect and prevents you from falling asleep.

4. wet sheet in front of the window

In addition to classic room darkening blinds etc., a wet bed sheet hung in front of the window can provide cooling, provided the floor conditions allow it. With tiles, special care should be taken to ensure that no puddles form on which you could slip when using the toilet at night.

5. lukewarm drinks before going to sleep

Similar to a cold shower, ice-cold liquid ensures heat production in the body. This means that ice-cold drinks are actually counterproductive in cold weather. Here too, lukewarm water makes more sense. Because as soon as the body actively reacts against the cold, it retains heat instead of dissipating it and cannot shut down for sleep. If ice cold, then only in small sips at a distance.

So: lukewarm water, if necessary. also put a glass by the bed for the night. This means you don’t have to get up when you need to drink.

6. no direct draughts on the body

As great as it may feel at first, the fan or air conditioning also have disadvantages. Because even if you cover yourself up, it can happen that you unwrap at night. If you then lie on the train, problems (dry mucous membranes, summer colds, neck pain and headaches) are inevitable, especially if you sleep naked. Cooling should therefore always be indirect.

7. air conditioning in the bedroom

In addition to the point just mentioned about using an air conditioning system, you should also pay attention to the temperature itself. “The cooler, the better” definitely does not apply here. The optimum bedroom temperature of 18 degrees is also not necessarily the best solution, especially if the difference to the outside temperature is too great. As a general rule, the difference between the inside and outside temperature is < 7 degrees. This means no more than 24 degrees in the bedroom at 30 degrees outside.

It also makes sense to cool the room down beforehand (approx. 1 hour) so that there are no draughts or noises when you fall asleep. Once you have fallen asleep, your body cools down a little on its own anyway. With good insulation, the room no longer heats up significantly. The situation is different in bedrooms with poor insulation. It can make sense to leave the air conditioning running at a low level at night.

But the same applies here: sensitive people should not sleep naked or on the train.

IMPORTANT: Heat rises upwards. This means that the temperature sensor of an air conditioning system should be at bed height and not under the ceiling.

8. open window

Of course, only if the outside temperature at night is actually significantly lower than the inside temperature of the room. Not everyone can sleep with the window open, but the natural coolness is always better and saves electricity. But here too, don’t lie on the train.

9. electrical appliances off, not just on standby

This is generally true all year round, but even more so in summer. Watching TV in bed heats up the room even more. And laptops, smartphones and tablets also emit enormous amounts of heat, which we tend to underestimate, quite apart from the other negative effects.

10. cooling bottle instead of hot water bottle

What works with a hot water bottle in winter can also help cool you down in summer. Put a hot water bottle with cold water (no ice!) in bed 20 minutes before going to bed. However (due to the known effect) this should be taken out of bed when we lie down. The aim is to enter a cool, but not cold bed.

11. nutrition

Nutrition plays a significant role in how we react to heat. Many heat deaths would still be alive if their bodies had not been robbed of their resistance by a poor lifestyle. The worse the physical constitution, the greater the problems in the heat. Especially diets that causecardiovascular problems. This point alone would fill books, which is why I only want to point this out here.

12. the most important tip last:

Don’t let the heat get into the bedroom during the day. This means: leave the blind down or close the curtain. External roller blinds are the best choice as they keep the heat out even before the window opens. Depending on the location, an awning over the bedroom window can also be an option during the day, even if it may look questionable at first.

Incidentally, this is a priority here in the south. Because all electric cooling costs money and harms the environment!


Always keep an eye on the measure and try to act with the body and not go one better or bypass bodily functions.

So what does all this have to do with heat death during sleep? Nothing. I was recently asked if you can die of heat exhaustion while sleeping. This question has a simple answer. I’m not aware of any cases of death from heat during normal sleep at night. If heart failure or similar reactions occur in the body, heat is usually not the cause but the trigger. Here too, the physical constitution determines the risk. Unfortunately, the word “cause” is also often used extremely laxly in medicine, but that is another topic.