Common nighttime mistake people make during heatwave that ruins sleep

With the UK in the hot throes of its fourth heatwave of the and while plenty of sunshine is predicted, so are potentially sticky and sweaty nights that could lead to restlessness.

Temperature plays a crucial role in determining sleep quality. The body requires cooling to both fall asleep and maintain slumber, yet when the mercury soars, this natural cooling mechanism becomes compromised.

This disruption makes drifting off considerably more challenging and prevents restorative rest.

Fortunately, Pretty You London has compiled expert-endorsed guidance to assist UK residents in remaining comfortable, cool and well-rested throughout the sweltering conditions, whilst revealing the common blunders you could be making during the heatwave that might disrupt your sleep during the hot temps.

Perhaps one of the biggest (and most common) mistakes people make during the heatwave is taking a cold shower at the end of the day — right before bed.

Whilst this approach might appear appealing, it proves remarkably counterproductive. Dr Hana Patel, NHS GP and sleep specialist at Time4Sleep explains: "A cold shower can cause your body to generate more heat as a response. A lukewarm or tepid shower is much more effective for gently cooling your core temperature before bed."

She additionally suggests applying cool (though not icy) water to pulse points – wrists, ankles, and forehead – to assist in reducing overall body temperature.

While sleeping naked during the heatwave might sound like the perfect solution - it's far from ideal. Dr Gareth Nye, biomedical scientist at the University of Salford and Theme Lead for Endocrinology at the Physiological Society, says sleeping naked is one of the most detrimental things you can do for quality rest and a good night's sleep.

Dr Gareth says: "When you sleep without clothes, the sweat you naturally produce stays on the skin. Unless that sweat is evaporated, the heat will remain on the skin - essentially keeping you from cooling down. As temperatures tend to drop during the night, sleeping naked might feel better at bedtime, but your sleep may be more disrupted as the night goes on."

This occurs due to how a person's body temperature fluctuates throughout the night and their natural temperature regulation mechanism. The doctor observes: "As temperatures tend to drop during the night, sleeping naked might feel better at bedtime, but your sleep may be more disrupted as the night goes on.

"Body temperature is controlled by a specialised portion of the brain called the hypothalamus. The process of controlling body temperature is called thermoregulation. If the brain is sensing the temperature is going up, it will open up blood vessels near the skin to route blood (which is warm) to the outside, which cools the core. Sweat glands will open up to release sweat, which cools the skin when it's evaporated away."

This process is also closely linked to an individual's circadian rhythm. "Normally, your body temperature will begin to drop as you approach your natural bedtime, which is controlled by your personal circadian rhythm - the cycles of hormones that control most of your body processes. Around two hours before you wake up, your body temperature will tend to go up," explains Dr Gareth.

If you're one of those still sleeping under a thick winter duvet - it may be time for a seasonal switch. A 4.5–7 tog option is better suited to spring and summer, and on those really warm nights, even a breathable bamboo or cotton sheet can suffice.

"People often think about changing their duvet in summer, but overlook the impact of their sheets and pillowcases," says Phoebe Street, Sleep Expert and Brand Marketing Manager at Pretty You London.

Polyester and other synthetic fabrics can hold in heat and moisture, leading to a sticky, uncomfortable night’s sleep. Natural fabrics like cotton and bamboo, on the other hand, allow for better airflow and pull moisture away from your skin, helping you stay cool and dry throughout the night.

"Using breathable, natural fabrics such as bamboo across your whole bedding setup can help to keep you cool, dry and comfortable, making a noticeable difference to how well you sleep when it's warm," adds Phoebe.

What you consume – and even the timing of your meals – can also influence your slumber during sweltering weather.

"Lighter meals are key in hot weather," says Alison. "Avoid spicy, oily and fried foods as these can increase sweating and interfere with digestion. Eating at least a couple of hours before bed helps your body wind down."

Opt for water-rich foods like fruit and salad, and keep any pre-bedtime snacks light if possible.

Dehydration can creep up on you during scorching weather, and it doesn't merely affect your energy levels throughout the day – it can disrupt your sleep, too.

Alison explains: "Poor hydration can cause night-time palpitations, which very effectively wake you up. Making sure you drink enough plain, still water throughout the day is one of the simplest ways to sleep better during warm nights."

She also recommends limiting caffeine or alcohol in the evening, both of which can dehydrate the body and diminish your ability to stay cool overnight.

Most high street nightwear in the UK is manufactured from synthetic materials, which tend to trap heat and perspiration against the skin, making sweltering nights even more uncomfortable.

You might be tempted to sleep naked to cool down, but Dr Gareth explains why that's not always the optimal choice: "Sleeping naked can actually keep sweat on the skin, which prevents cooling. Loose, breathable clothing allows sweat to evaporate and helps you stay cooler throughout the night."

The superior solution is to opt for natural, breathable materials such as bamboo viscose or organic cotton. Whilst they may require a slightly higher initial investment, these fabrics draw moisture away, permit air circulation and assist in regulating your body temperature. Moreover, they generally wash more effectively and prove more durable.

Illumination plays a vital role in controlling your body's internal timekeeper, or circadian rhythm, which dictates when you feel drowsy. "Exposure to bright or blue light in the evening can delay melatonin production, making it harder to fall asleep," explains Alison.

To assist your body in preparing for rest, reduce your lighting an hour or two before bedtime and restrict screen time during this window. Employing blackout curtains or an eye mask can also help prevent early summer morning light, permitting longer, more peaceful sleep.

Throughout the day, strive to receive abundant natural light to maintain your internal clock on schedule.

"Keeping your bedroom cool is key for good sleep during hot weather," says Alison. "The body needs to drop its core temperature to trigger sleep, so a warm room makes this difficult."

Shut blinds or curtains throughout the day to prevent heat, then open windows in the evening to allow fresh air inside. Should temperatures stay elevated, a quiet fan can prove beneficial, provided you're comfortable with the sound.