15 common sleeping myths debunked by science

We all love sleep, but many of us aren’t getting it right. Britons are now said to be the among the world’s worst sleepers, with our recent survey revealing that over a quarter (28%) of people aren’t satisfied with the quality of sleep they’re getting.

Sleep is absolutely vital for our bodies and minds to function properly. This complex bodily state transcends the realms of both physical and mental wellbeing, and as a result, it’s become a misunderstood area of science.

To clear things up once and for all, we’ve spoken to three sleep experts in the UK to give us the answers we’ve all been waiting for: are these merely myths or do they speak some scientific truth?

Meet our sleep professionals. Each is contributing a wealth of experience from their particular field of expertise to give us a well-rounded approach in our bid to separate fact from fiction.

• Alison Gardiner: Co-creator of Sleepstation, an online insomnia treatment based on CBTi that has been clinically proven to work better than face-to-face treatment.
• Lisa Artis: Spokesperson for the The Sleep Council, an impartial, advisory organisation that raises awareness of the importance of a good night’s sleep to health and wellbeing.
• Adam Atkinson: Personal Trainer at Diets Don’t Work who believes that sleep is the third pillar of health and fitness.

These experts all have one thing in common: using science to help us sleep better. So we’ve asked Gardiner, Artis and Atkinson to use their scientific minds to debunk the 15 most common sleeping myths of our time:

According to Atkinson, catching up on sleep is a myth: “A recent study by the University of Pennsylvania and the University of South Australia showed that you can’t fully catch up on sleep. Even after two weeks of recovery sleep, sleep deprived subjects’ brain function in cognitive tests was still poorer than those who slept for at least seven hours a night.” He also points out that a reduction in sleep even for one night will significantly decrease the effectiveness of the immune system.

Artis agrees that catching up on sleep doesn’t fix all the deficits caused by sleep loss: “A few days of lost sleep can have adverse effects including increased daytime sleepiness, worsened daytime performance, an increase in molecules that are a sign of inflammation in the body and impaired blood sugar regulation.”

Gardiner’s solution? “It’s much better to stick to regular sleep hours, going to bed and getting up at the same time each day, even on weekends.”

All three experts agree that sleeping pills are not a long-term solution, as they temporarily mask the symptoms of problematic sleep without addressing the root cause.

Gardiner points out that “you are not meant to use sleeping pills for longer than four weeks at a time. Despite this, there were over 12 million sleeping pill prescriptions in England last year.”

Even more worryingly, Atkinson says that the long-term side effects are as bad as sleep deprivation itself: “They range from drowsiness, memory loss and blurred vision to mood swings and irritability.”

Gardiner suggests using cognitive behavioural therapy for insomnia (CBTi) instead of sleeping pills, as it changes your behaviour around sleep, making it a more effective long-term and drug-free solution.

It’s agreed that most dreams occur during REM (Rapid Eye Movement) sleep, yet it takes most of us around 60 to 90 minutes to enter this cycle.

However, Gardiner explains that dreams can occur outside of REM if you have a condition such as narcolepsy: “People with narcolepsy only take around 15 minutes to enter REM sleep. The boundaries between wakefulness and sleep are less distinct, and elements of sleep and wakefulness can mix together. This means they can suffer hallucinations while waking.”

Read our article on understanding your sleep cycle to learn more about REM sleep and dreams.

Our experts all agree that the ideal nap should be no longer than 20 minutes to avoid falling into deep REM sleep, which can leave you feeling groggy. Atkinson calls these short power naps “highly restorative and beneficial”.

Artis explains: “A short kip can give you as much energy as two cups of strong coffee, but the effects are longer lasting”.

However, longer sleeps during the day can indeed lead to difficulty in falling asleep at night. Gardiner suggests limiting naps: “If you suffer from sleeping problems such as insomnia, naps will only exasperate the problem. If you aren’t sleeping at night, but are sleeping in the day, then there’s a chance you are throwing your sleep cycle off.”

The experts all recommended that alcohol should be avoided if you’re looking to get a good night’s sleep. Artis and Gardiner agree that you may feel the sedative effects of alcohol that help you fall asleep initially, but your sleep will be disturbed later on in the night.

Atkinson discusses a review of 27 studies, which “showed that drinking depletes REM sleep, the period in which the most repair and regeneration occur within the body. It also makes you more likely to get up in the night to use the toilet and is a diuretic, so will leave you dehydrated.”

Whilst eight hours is generally considered the optimal amount of sleep, Artis and Gardiner believe it varies from person to person as everyone’s requirements are different. They agree that the best indicator of good sleep is how you feel the next day. If you’re exhausted then you probably aren’t getting enough, but if you’re groggy then you could be getting too much.

Atkinson, on the other hand, highlights leading sleep studies from the University of California: “Any human being getting less than six hours sleep a night will suffer a large range of health problems, from increased chances of disease to weight gain.”

Atkinson goes as far as to say that “your old mattress could quite literally be killing you.” He explains that “whilst there are many factors that contribute to a good night’s sleep, the most important is the correct mattress.”

Our experts propose that the foundation of a good night’s sleep and a healthy back is a comfortable, supportive bed. Artis explains that “after seven years, even a good quality bed will have been subjected to a lot of wear and tear — over 20,000 hours of it — and won’t be performing at anything like its best anymore… All too often people wait until they’re actually suffering before replacing their beds, when they should act before it gets to that stage.”

However, as Gardener reminds us, “If you have a comfortable bed but still can’t sleep then there is probably something more serious going on and you should consider seeking treatment for your sleep problem”.

See our beds buying guide or the video below to help you find the perfect match for your sleeping style

We found our experts divided on the long-debated topic of cheese. They all agreed that there’s no solid evidence to suggest it causes nightmares. However Gardiner warns that “eating heavy meals before bed can interrupt your sleep, so maybe don’t pull out the cheeseboard just before bedtime.”

Artis, on the other hand, is a big fan of cheese. She even recommends it as a bedtime snack: “Calcium, found in cheese, is a natural sleep aid as it contains tryptophan, an amino acid the body uses to produce melatonin (the sleep inducing hormone).”

According to our experts, it’s a myth that waking up a sleepwalker can cause a heart attack, shock or even kill them. However, Gardiner comments: “Sleepwalking normally happens in slow wave sleep, a very deep stage of sleep. This means they can become extremely confused, and can even end up lashing out or physically harming the person who woke them.”

Artis recognises that it can be a concern to leave a sleepwalker wandering around. She suggests “gently returning them to their bed — and if that doesn’t work, make loud noises from a distance to try wake them.”

Atkinson tells us about the world’s leading sleep professor Matthew Walker from the University of California, who encourages readers to recognise the signs of sleep deprivation, the first of which is yawning.

Yet, Artis points out: “There can be several reasons why we yawn besides being tired.” Gardiner agrees that yawning has been linked to other emotions, as “some people yawn when they are stressed or anxious”. She also mulls over the phenomenon of contagious yawning; “It still remains an unexplained mystery to scientists. We are not the only species to yawn when others around us do so, chimpanzees and dogs do as well.”

Gardiner praises exercise as “a great way to help you sleep at night.”

Artis agrees: “Releasing pent up tension through exercise is also highly beneficial, helping to banish stress before bedtime. Exercising also lowers your body’s temperature, which induces better sleep.”

However, as personal trainer Atkinson highlights: “In most forms of exercise where the heart rate is elevated, the body produces two hormones, endorphins and cortisol. These two hormones make us more alert and less likely to sleep.”

Artis agrees that exercising close to bedtime can disturb sleep and increase alertness. They suggest slower, meditative forms of exercise close to bedtime, with yoga being first choice for its relaxation and sleep benefits.

The sleep experts all agree that sleeping less doesn’t make you lose weight, in fact, it can have quite the opposite effect. Atkinson explains how this encourages weight gain on many fronts: “It decreases the ability of insulin to move sugar from the blood stream increasing fat storage and making the onset of type two diabetes more likely. It also increases the presence of the hormone cortisol which encourages fat storage for survival.”

Gardiner agrees, putting it down to the hormones that regulate our hunger, ghrelin and leptin: “The impact of poor sleep on these hormones means when we wake up we are more likely to crave high sugar foods rather than healthy options.”

However, Artis and Atkinson both point out that too much sleep (over nine hours) can be equally as harmful: “It has been linked to chronic diseases such as diabetes, coronary heart disease, obesity and anxiety, especially in those aged 45 and over,” explains Artis.

Counting sheep is an old wives’ tale that has been around for centuries, but does it actually work? Gardiner isn’t convinced: “The cognitive load of counting sheep is too low. It doesn’t require much thought, so other thoughts can take over.”

Instead, she suggests a technique called thought-blocking to switch off your brain at night. This involves counting backwards in sevens, which “requires more cognitive load and stops you from worrying”, so that you can drift off without realising. Artis advocates these exercises, recognising that “absorption in a mental task is an aspect of mindfulness and can help to relax you”.

Artis and Atkinson agree that it’s a common misconception that sleep needs decline with age, while Gardiner suggests that sleep simply changes as you get older, as most over 65s struggle to sleep for more than six and a half hours per night.

Atkinson argues: “Confusion with sleep needed and actual sleep in the elderly is thought to be the source of this myth. Older people tend to sleep less due to health issues, psychological problems and medication, but this is no indicator of sleep needs. It is rather a measure of sleep deprivation.”

Artis suggests looking at the bedroom environment, adjusting daily routines as sleeping patterns change and trying to limit the cat naps, to avoid this common issue.

Our sleep experts warn against using screens before bed. Atkinson explains: “A study by Harvard Medical School showed that it increases levels of cortisol and adrenalin, both designed to keep us alert and ready to flee or fight perceived danger.”

Artis adds that “the bright light from TV plays havoc with your body’s circadian rhythms (internal body clock).”

Gardiner advises to stop looking at screens an hour before bed, suggesting: “You’d be better off listening to something rather than watching it. The truth is that everyone is different, and if something helps you get to sleep, as long as it’s not overly stimulating then it’s helpful.”