Courtney Greene, Head of Occupational Therapy at Cygnet Hospital Woking and Woking Lodge has answered some questions on why sleep can be so difficult during a heat wave in summer and has given some tips and advice on how to still get some quality shut eye.
1. Why do some people struggle to sleep during the summer?
In the summer, we have longer days with more sunlight hours, resulting in more stimulation by sunlight later in the day.
As the day lengthens, our natural sleep pattern, called the circadian rhythm, is delayed.
Exposure to long summer solstice days may impact our sleep-wake cycle and circadian rhythms by delaying the melatonin secretion that informs our brains that it’s time for rest.
The warmer weather that often accompanies summer also can make it harder to fall asleep and stay asleep. Your body naturally cools down as it is preparing for slumber, but if your home or your room is too warm, it is likely you will get less sleep.
During the summer months, people often have an increase in social activities, work events, and other social factors that can lead to later bedtimes and disrupted sleep schedules.
2. What is the ideal temperature for sleeping?
It is actually harder to sleep when it gets hotter, because when your body is getting ready to sleep, its temperature decreases.
To create a healthy sleep environment, you need to reduce the temperature in your bedroom. A good night’s sleep is also dependent upon temperature. Sleep experts recommend the best temperature for sleep to be around 18.3 degrees Celsius.
When your bedroom is much warmer or colder than this, it can stop you from falling asleep and affect the quality of your rest when you do.
Our bodies require a skin temperature of between 31-35C. In the summer, when higher temperatures are more common, this can be harder to control, particularly during heatwaves.
3. How does the heat affect our body? What parts of our body does it affect?
Heat affects our core body temperature. In order to fall asleep, our core body temperate needs to reduce and drop, however, if we are too hot, this does not happen and will affect our ability to fall asleep, and stay asleep.
4. How does the heat affect us mentally? And how does this disrupt our sleep?
Heat can make it harder to focus or think clearly.
High temperatures, especially at night, can disrupt your sleep. Lack of sleep can make you feel tired, grumpy, and can worsen mental health conditions like anxiety and depression.
Heat can also cause physical symptoms that affect your mental health. For example, you might feel more tired than usual, have headaches, or feel dizzy or nauseous.
These physical symptoms can make you feel anxious or down.
You might find yourself acting differently when it’s hot. For example, you might be more impulsive, or you might have a hard time controlling your anger.
5. Is there anything we can do during the day to help us sleep better at night?
– Limit alcohol intake. In summer, we tend to feel like we are on vacation and therefore increase our alcohol intake which directly affects sleep. Although alcohol may make you feel sleepy at first, it wears off a few hours later and has a wakening effect on the brain.
– Wear sunglasses to block out sunlight to reduce stimulating your eyes.
– Exercise earlier during the day, not before bed time. This is because exercises raises your body temperature.
– Don’t have a hot shower/ bath too close to bed time.
6. How can I cool down before getting into bed?
– Take a lukewarm shower two hours before bed
– Use Water Spray: A cooling mist of water can be just what you need to lower your temperature on a hot night. Fill a spray bottle with chilled water and keep it by your bed. You can use this to spritz yourself in hot moments throughout the night and cool off. The neck and wrists are particularly good areas to spray, given their high blood flow.
– Make a Cold Water Bottle: Many of us will have used a hot water bottle to stay warm in the winter, without having considered using one in the summer. On a warm night, try filling a water bottle with cold water and even some ice, then placing it in your bed a little while before you go to sleep – be sure to screw the lid on tight though, so that your mattress doesn’t get wet! This will lower the temperature and absorb heat throughout the night.
7. Are there any tips / products that might help people sleep better during the summer?
– You can create an artificial night time: Get blackout blinds, and reduce amount of lights on in the house in the evenings.
– Make sure your bedroom is dark and at a cooler temperature. You also may want to switch out your bedding for a lighter version and opt for blackout curtains to keep your room cool and dark.
– Sleep experts recommend sleeping with your arms and legs spread out. Doing so, helps you release body heat instead of retaining it.
– Choose sleepwear that is made with natural fibres like cotton, light wool, or silk
– Air circulation is key to staying cool in the summer nights and opening a bedroom window is the simplest way to do this. However, you should not have your windows open all day; this can allow warm external air and bright midday sun to increase the temperature inside further.
– At the warmest points of the day, keep your windows and curtains closed to minimise the amount of hot air and light that enter your bedroom. Open your bedroom windows once the sun is setting and allow the cooler evening air to ventilate your bedroom.
