So, what can we do to improve our sleep in the heat, especially when we don’t have the luxury of air-con? And can’t we just use a fan?
It has been suggested that the optimal temperature for a good night’s sleep is 18.3°C, with a range from 15.6 to 19.4°C being acceptable. The reason for this is that when you go to bed, your core body temperature drops and your metabolism slows in preparation for sleep. To help reduce your core temperature, blood is diverted to your extremities (skin, hands and feet), to let some of your body heat escape. The body continues to cool until reaching its minimum temperature near daybreak or at around 5 am. If the room around you is too hot or cold, this can affect your body’s ability to perform this thermoregulation, which in turn disrupts your sleep.
In hot weather, as the body struggles more to lower its core temperature, it is harder to fall asleep and harder for the body to enter and stay in the deepest cycles of sleep. This is why you might experience those hours of tossing and turning when you get into bed on those sticky summer evenings. In addition, studies have shown that in normal sleep situations where people wear pyjamas and sleep under bedding, heat exposure leads to increased wakefulness and reduces both slow wave sleep and rapid eye movement sleep. As well as the temperature itself, humid heat has also been shown to affect different sleep stages due to its impact on the body’s thermoregulation.
The obvious solution to tackle those hot sleepless nights is to cool down your bedroom. However, here in the UK, where hot nights are generally a rarity, so are the good-old air conditioning systems that the majority of the civilised temperate world depends on. In 2008, it was estimated that only 0.5% of UK homes had any form of built-in air conditioning. Meanwhile, in the US, more than 100 million homes have air-con. This lack of air conditioning in the average UK home has left many of us sneaking surreptitious relief in our cars during the heatwave, blasting the A/C on full, relishing the artificial breeze.
So, if we can’t cool our bedrooms with A/C, and opening the window merely creates a convenient entrance for the UK’s wonderfully curious cornucopia of insects, many of us may consider proudly installing a portable fan. But beware, sleeping with a fan on may feel glorious, but can be accompanied by some rather undesirable side effects. Having air continuously blown over you while you sleep can dry out your mouth, nose and throat, leading to an overproduction of mucus, meaning that you may wake up feeling congested, dehydrated and headachy. Fans can also dry out your skin and circulate dust and pollen, triggering allergies and irritation. The constant supply of cool air can also cause our muscles to cramp while we sleep, meaning that we feel stiff and sore when we wake.
If fans aren’t the solution, then what can we do to avoid that aggressive fear that one part of our sweaty body might dare to touch another part within the inferno of our bed sheets?
Here are 7 simple steps to help you sleep better in the heat:
1. Daytime routine – although the heat may make you feel sleepy during the day, and the idea of a siesta may almost be attractive enough that you apply for Spanish citizenship, you must not nap during the day if you want to sleep at night. Maintaining normal daytime routines, including exercise, is very important for ensuring you save your tiredness for the evening.
2. Hydrate – Making sure you have enough to drink before you go to bed will help stop you waking up feeling parched. You should even consider having a hot drink, as your body will respond by initiating cooling mechanisms to counteract its effects. However, you don’t want to drink too much, and avoid diuretics like tea and alcohol, or else you’ll be waking up for a wee instead. This could be particularly troublesome if you live in a shared house and decide to sleep…
3. Naked – reducing that one extra pesky layer of material between you and the air is a great way of preventing a warm barrier of air building up around your skin. If you already sleep naked, try poking your feet and hands out of the sheets – these body parts have a large surface area to encourage heat loss.
4. Sleeping on your side is also said to expose more of your body to the outside air if you’re one of those people that needs to sleep under a sheet, even when its sweltering.
5. Sheets – If you do need some form of cover for comfort, choose thin cotton sheets that absorb sweat and have breathability. In extreme conditions, you could even pop your sheets in the fridge before clambering into them.
6. Keep your bedroom cool – keep blinds or curtains shut and windows open during the day to keep the sun out and prevent the room from warming up. As heat always rises, one of the best ways to keep your rooms cool is to open any attic windows. This lets all the heat out the top of your house. This phenomenon of heat rising is also why…
7. Sleeping low keeps you cool. Sleeping on a mattress on the floor is strong in Japanese culture. There is no reason why we too could not adopt this strategy in the warmer months to ensure that we lay below the warmest layers of air.
One very important solution that we have overlooked so far, that may apply to many of us, is that our bed partners are an enormous, snoring source of overwhelming heat.
So, if all else fails, we can always kick our other half out of bed and tell them it’s cooler down there on the floor anyway.