5 things you need to know about sleep

Everyone needs sleep. It is an important part of our daily routines and is as essential to survival as food and water.

Without sleep, our brains cannot perform many vital functions, and it becomes harder to concentrate, respond quickly and manage stress. Getting poor quality sleep can even increase the risk of physical disorders, including high blood pressure, cardiovascular disease, diabetes, depression and obesity.

People who struggle with insomnia and other sleep disorders would give anything for a good night’s sleep. But many people underestimate its importance and take it for granted. We look at five things that you should know about sleep.

1. Sleep better, live longer

Sleep scientist Matt Walker from the University of California, Berkeley, says good quality sleep should be seen as a non-negotiable biological necessity, rather than a lifestyle luxury.

In this popular TED Talk, he explains why sleep is your superpower. He says lack of sleep can age you by 10 years and is a factor in many diseases, including age-related cognitive decline, Alzheimer’s disease, cardiovascular problems and even cancer.

In 2019, a working group of 27 scientists from 16 countries met at the International Agency for Research on Cancer and concluded that night shift work is “probably carcinogenic to humans”. They said that being exposed to artificial light at night can disrupt circadian rhythms and inhibit melatonin production, which is thought to help prevent cancer.

On the flip side, decent sleep restores and enhances our ability to learn. Being well rested makes our bodies more resilient and better able to fight disease, boosting our immune cells and giving time for the body to repair itself. Dr. Maiken Nedergaard, professor of neurology at the University of Rochester, and her colleagues found that the body uses sleep to remove toxins from the brain, which might include the amyloid plaques that contribute to Alzheimer’s.

2. Timing is everything

Our bodies are governed by daily patterns, or “circadian rhythms”, that tell us when to wake up and when to fall sleep. And sometimes those rhythms are thrown out of sync. According to this paper by international sleep academics, we each have a “chronotype” – some of us are larks while some of us are owls. Larks like to go to bed early and rise early, and owls go to bed late and rise late. Our own personal circadian rhythm can be genetic.

Neurology professor Ying-Hui Fu of the University of California claims there’s a gene that enables some people to survive on less sleep than the eight-hour norm. Former British Prime Minister Margaret Thatcher famously survived on only four hours of sleep a night.

But this is not for everyone. Arianna Huffington, co-founder of The Huffington Post, says sleeping for three to four hours a night led to burnout. Her recent book calls for a sleep revolution and says transforming her relationship with sleep has also improved her mental attitude: “I’m much more present in my life, much more joyful. I am, without question, a better leader, because I can look ahead with more clarity.”

3. Sleep restores and protects our brain

Humans need rest in order to regulate and process the stresses of the day. Sleep plays an important role in regulating emotions. In a recent article for the science journal Frontiers, academics from the University of Helsinki say that people need deep REM sleep in order to process emotions, and people who experience poor, disrupted sleep can find it more challenging to “downregulate” emotional distress.

Stress and poor sleep go together. When we worry, it’s difficult to switch off at night. According to this study published in medical journal The Lancet, stress caused by the COVID-19 pandemic had a marked impact on healthcare workers and COVID-19 patients. Sleep problems were found in both groups to be associated with higher levels of psychological distress, including depression and anxiety. The general public also experienced increased sleep problems, with fear of COVID-19 and stay-at-home measures disrupting the sleep-wake cycle.

4. You can’t bank sleep

The trend for skimping on sleep has been called “revenge bedtime procrastination” – sabotaging sleep in order to reclaim some time for yourself at the end of a busy day.

Cal-Berkeley sleep expert Matthew Walker says you can’t cheat sleep: “Human beings are the only species that deliberately deprive themselves of sleep for no apparent reason. And that means that Mother Nature has never had to face the challenge of sleep deprivation during the course of evolution and therefore, she’s never had to come up with a safety net mechanism that overcomes a sleep debt.”

5. How to get our sleep back on track

Tips for improving sleep include getting up and going to bed at the same time, exercising during the day, avoiding caffeine and sugar before bed, and keeping your bedroom cool and dark. Experts also recommend turning off all devices to avoid the blue light from technology, which can inhibit melatonin production and disrupt circadian rhythms.

If your poor sleeping habits are still hard to break, then we need to stop trying too hard with new pillows, mattresses and apps, says Dr. Julian Lim from National University of Singapore. He says mindfulness-based therapy can help: “Sleep is a natural process, and by worrying about it too much we are only making matters worse….Mindfulness can help us have a different relationship with our thoughts about sleep.”

To help you drift off, you could try systematically relaxing your body, muscle by muscle – it's a technique used by the military to go to sleep quickly, anywhere, any time. It’s even been going viral lately on the social media platform TikTok.