How to cool off in a heat wave: should you really drink tea and sleep naked when it’s hot?
Nothing like a British heatwave to bring out a long list of extreme weather advice. While temperatures are expected to stay warm this week, what advice should you follow? We asked the experts … The claim: Keep all your windows and curtains closed The truth: “It’s natural on a hot day to keep all your windows and doors open,” says Dr Alannah Hare, NHS consultant and private sleep at the Royal Brompton. âHowever, the best thing you can do is keep your windows closed and your curtains drawn all day. This is all due to temperature variations. When you open your windows in the morning it is cool and pleasant, but when the sun rises all day it heats the interior of your home. âIf you keep your windows and curtains closed until dusk, however, your house will be very cool when you go to bed. As the sun sets, open your curtains and windows and you will feel a gentle breeze coming through your house, which will help you sleep. Verdict: True The Claim: Drinking hot tea to cool off The Truth: It has long been established that staying hydrated is essential during a heat wave. However, whether or not you should heat an infusion has been the subject of intense scientific debate. In 2012, a landmark study by Ollie Jay of the University of Ottawa sought to find an answer once and for all. The team found that when thermosensors in the mouth and throat detect heat, the brain activates a sweat response. The sweat then absorbs body heat and evaporates it into the air. As a result, they concluded that drinking hot drinks can cool you down in certain environments. Drinking a hot latte while wearing long sleeves and pants will not work, as the sweat must evaporate and the temperature drop caused by sweating must exceed the temperature rise caused by consuming a hot drink. . But drinking tea in a summer dress or short-sleeved shirt can help cool off slightly. Verdict: True The Claim: Have a hot curry The truth: Gazpacho, ice cream, cold fruit salad – and, curry? There are several foods that can have a cooling effect, and it seems that one of them is chili. It may seem counterintuitive – anyone who’s had a really hot curry will know why – but it does make sense, given that most of the spicier cuisines in the world are found in hot climates. The theory is simple: fight fire with fire. Hot and spicy food, which usually contains chili pepper, contains a chemical called capsaicin. When eaten it warms the body and you start to sweat. Evaporation of this sweat removes heat from the body. It is assumed that cold foods will only cool you for a short time, while hot and spicy foods will provide longer term cooling. Several other ingredients often found in curries are believed to have cooling properties, such as turmeric. It should be noted, however, that in order to sweat you need to stay hydrated, so drink plenty of water. Verdict: true (but it might not sound like it) The statement: Stay out of the sun The truth: âThis week the sun is high enough in the sky and strong enough to provide a very good dose vitamin D, âsays dietitian Helen Bond. âIt’s wise to be careful in the sun, and I certainly wouldn’t recommend sitting in a beer garden or park for a few hours in the midday sun. But a 15-minute walk with your hands, face, and arms in the sun will give you a fantastic amount of vitamin D to keep your levels level all year long. Verdict: False The Claim: Drink a cold beer tonight The Truth: âBrits tend to be very excited about a sunny period,â says Bond. âHowever, drinking too much alcohol during a heat wave is about the worst thing you can do. In cold weather alcohol dehydrates, but in hot weather the effects are increased tenfold and if you drink during the day and outside you are more likely to burn yourself because the pleasure of drinking keeps people grounded in place. A few beers are fine, but no more, and have a glass of water before, between and after each beer. âPeople tend to drink more Pimms and beer during a heat wave, and then have a double kick of bad sleep, from the effects of alcohol and heat,â Hare adds. “So drink moderately.” Verdict: False The Claim: Take a cold shower before bed The truth: âIt’s something people always tell me to do when it’s hot, but it doesn’t work,â Hare says. âAfter a long, hot day in an office, it’s tempting to blow yourself up in a cold shower right before bed. But the problem is, the body then raises its core temperature to compensate for the cold water, which makes you feel warmer once in bed and makes sleep more uncomfortable. It is best to take a lukewarm bath or shower so that your body does not try to warm up. Verdict: False The Claim: Put Your Pillow in the Freezer The Truth: We’ve all heard this one, but does it actually work? âYeah, but don’t put your whole pillow in there, just the pillowcase,â Hare said. âAbout an hour before you go to bed, put your pillowcases in a plastic bag and put them in the freezer for about 40 minutes. Then put it on right before bed, and it will be nice and cool on your skin. Do you know that feeling you get on a hot night when you flip your pillow over to feel the cool side? It’s like that, but a hundred times better. Verdict: True The Claim: Sleep Naked The Truth: âPeople always ask me about this,â Hare says. âIf you wear natural fibers, like cotton, you will feel cooler at night than if you were naked, because the cotton will wick sweat away from your skin. However, anything man-made or synthetic will keep the heat close to your skin. And the same goes for bedding. So if I had the choice between cotton and nudity, I would choose cotton. But if you choose between man-made fibers and nudity, go nude. Verdict: Inconclusive The Claim: Don’t Exercise The Truth: Training can be a sweat affair – although some hardy souls will continue regardless. Exercising in extreme heat places additional stress on the body and can be dangerous, leading to a range of heat-related illnesses, from heat cramps to heat stroke. That doesn’t mean you have to avoid it altogether – but you do need to understand how to recognize the symptoms and know your limits. The warning signs, according to the Mayo Clinic, are numerous, including cramping, nausea, excessive sweating, dizziness, increased heart rate, and visual problems. “By taking a few basic precautions, your exercise program should not be put aside when the heat is on.” Here are some tips from the Mayo Clinic: Know how fit you are. If you are new to training, be very careful. Go for something less intense and stay hydrated. Hydration is the key. Drink regularly and don’t wait until you are thirsty. If you are sweating heavily, consider an isotonic sports drink, which will replace minerals and nutrients lost through sweating, such as sodium, chloride, and potassium. Wear the right gear. Keep it light and loose, and choose a material that promotes evaporation. It is better to avoid dark colors, which absorb heat. Cover yourself with a hat and wear lots of sunscreen. Sunburn will interfere with your body’s ability to cool down. Exercise early in the morning to avoid the worst of the heat Verdict: False-ish The Claim: Read Heatwave Tips (like this one) The Truth: âThere are two things the British like to talk about – the weather and their sleep, âHare says. âDuring a heat wave, people start to panic about their sleep, which will prevent them from sleeping. So try not to worry too much about it. Maybe your sleep will be a bit disturbed, but it’s okay. You will be able to get enough sleep to get by. And just think that in a few months it will be cold again, and we’ll start worrying about it again instead. Verdict: Inconclusive Telegraph Readers Share Their Heatwave Sleep Tips Here is a selection of the comments you left on our heatwave stories. Please continue to share your tips with us in the section below this article. Jasmine Maddock: I put an ice pack in the bed for a little while to cool the bed, and I find that a cup of tea helps because paradoxically the heat cools your body. Mikel Crawley: We put a duvet on the floor near an open door for air to pass and sleep on the duvet cover. Linden Airey: If you wear clothes in bed, slightly dampen the clothes. With that kind of heat, humidity can be your friend! If you can’t fall back to sleep after waking up at night, use a damp washcloth to cool your skin. Anonymous reader: put a large bath towel on your bed Take a cool or barely lukewarm shower Lie on your towel, still wet – preferably naked Ideally, also have a fan blowing towards the bed at low temperature Water s ‘will evaporate on your body and lower your temperature Stay slightly moist and cool off while the water is also evaporating. What are your heatwave tips? Tell us in the comments below