18 March 2022 marks the 15th annual World Sleep Day. This year’s theme is Quality Sleep, Sound Mind, Happy World. Quality sleep may not solve global problems, but it can revitalise your world by boosting your mental, emotional and physical wellbeing. That’s what I want to talk about today — the importance of sleep. I know you’ve probably heard or read about this before, but have you ever wondered how something as mundane as sleep could be so fundamental to our health? More importantly, what’s keeping you from reaping the incredible health and wellness benefits of quality sleep?
Sleep does more than recharge the battery you gradually run down throughout the day. Here are some science-backed facts I’d love to share with you about the importance of sleep.
What is quality sleep?
Let’s first understand what quality sleep means and why we need sleep in the first place.
The question of why we sleep is a difficult one to answer. Scientists have tackled this question from many different angles. For instance, researchers have looked at the effects of sleep deprivation in humans and other animals, recorded neuron activities in slumbering brains, closely observed sleep patterns in different organisms and studied sleeping disorders to decipher the mysteries of sleep.
Sadly, sleep is a complex and challenging subject to study, and decades of sleep research have only raised more questions. But the numerous studies have so far immensely expanded our understanding of sleep and yielded some robust theories explaining why we sleep, including:
- the evolutionary theory
- inactivity theory
- energy conservation theory
- brain plasticity theory
In a nutshell, sleep quality measures how well you sleep. It’s different from sleep satisfaction and quantity but closely related to both. Four interrelated elements determine the quality of sleep:
- sleep latency – the time it takes to fall asleep
- sleep-waking – the frequency of waking up in the night
- wakefulness – the amount of time you stay awake when you should be sleeping
- sleep efficiency – how much time you spend sleeping while in bed (expressed as a ratio or percentage)
These factors combine into the overall sense of satisfaction, rejuvenation and restfulness you get from sleep. Poor-quality sleep could mean you take too long to fall asleep, wake up too often after falling asleep or stay up too long after sleep interruptions. All these can negatively affect your circadian rhythm, sleep cycles and sleep quantity, resulting in sleep that does you more harm than good.
The importance of quality sleep
Getting quality sleep is like hitting a big refresh button. Your body and brain regulate and check your metabolism, energy levels, mood, mental functions, hormonal balances and immune system activities while you sleep.
The brain remains curiously active when asleep, and some brain functions have been observed exclusively during certain stages of sleep. Scientists believe these are responsible for memory consolidation — how the brain links waking sensory experiences to learn and form new memories. Neurological studies also suggest a correlation between quality sleep and pain and anxiety relief. Ultimately, the physiology of quality sleep improves your mental, physical and emotional wellbeing in the following ways:
- sharpens the brain through improved cognition, memory, reaction time, concentration and problem-solving abilities
- enhances fine motor skills, muscular endurance, balance and coordination
- maintains cardiovascular health
- regulates metabolism, which in turn checks weight gain, blood sugar levels and energy reserves
- boosts your overall mood
Another way to understand the importance of quality sleep is to look at the effects of sleep deprivation. Several studies link poor sleep to depression, impaired immune functions, social and emotional indifference, low cognitive performance and high risk of diabetes and cardiovascular diseases.
Most of the effects of poor sleep are bidirectional. For instance, if you’re stressed during the day and don’t get quality sleep at night, you’ll wake up even more stressed, creating a positive feedback loop that may eventually lead to wild mood swings, behavioural disorders and even depression.
Why are we not getting quality sleep?
According to the Philips Global Sleep Survey, most people agree that sleep is a crucial contributor to mental and physical wellbeing, citing better mood, memory and performance after a good night’s sleep. However, barely half of the respondents said they were satisfied with their sleep.
Image source: Philips Global Sleep Survey 2020
So, it’s not that we don’t appreciate the importance of sleep; we somehow can’t seem to get enough of it. The demands of modern lifestyles (juggling work, family, personal and social life) can get in the way of some quality shuteye. But I could argue that sleep disorders and poor sleep hygiene are the main reasons we’re not getting the much-needed quality sleep. Hear me out.
About sleep disorders
Twenty percent of adults in the UK have trouble falling asleep every night. In the US, sleep disorders affect as many as 70 million individuals.
Sleep experts have identified over 80 diagnosable sleep disorders. However, most are treatable or manageable with suitable mediation or behavioural therapy. The five most common sleep disorders are:
Nearly a billion people worldwide suffer from sleep apnoea, yet most cases go undiagnosed. Sleep apnoea happens when breathing is interrupted during sleep, causing a person to wake up suddenly.
Patients with sleep apnoea are classified in one of three categories:
- obstructive sleep apnoea (OSA) – results from blocked airways when muscles in the throat relax
- central sleep apnoea – occurs when neurological signals fail to maintain the normal breathing rhythm
- complex sleep apnoea syndrome – a combination of both OSA and central sleep apnoea
In addition to the implication of sleep deprivation, sleep apnoea causes other problems, including snoring, night terrors, restlessness, sleep fragmentation, night sweats and morning headaches. If left unchecked, sleep apnoea can even exacerbate or increase the risk of cardiovascular illnesses.
Insomnia refers to difficulty in falling and staying asleep. Acute insomnia is short-term and often caused by sudden interruptions in daily routines, such as travelling. Chronic insomnia is more problematic and may well have a biological aetiology.
Restless Legs Syndrome (RLS)
RLS is characterised by an irresistible urge to move the legs, which typically starts in the evening or during sleep. People with RLS may have a hard time falling and staying asleep. It’s unclear what causes this condition, but researchers suspect it has to do with the neurotransmissions responsible for controlling muscle movement.
REM Sleep Behaviour Disorder (RBD)
RBD is a condition in which a person acts out their dreams with vocal sounds and sudden (usually violent) movements when asleep. When dreaming, people with RBD lack the paralysing nerve pathways that prevent muscle activation. This condition is distracting and can even be dangerous.
People with narcolepsy struggle to stay awake for long periods regardless of where they are or what they’re doing. Type 1 narcolepsy is accompanied by a sudden loss of muscle tone (cataplexy). The exact cause of narcolepsy is unknown, but patients with Type 1 narcolepsy exhibit low levels of hypocretin, a neurochemical that regulates wakefulness.
Poor sleep hygiene
Sleeping disorders are not solely to blame for poor sleep quality. Our everyday habits play a role in how well we sleep too.
Bad sleeping habits can contribute to poor sleep. Here’s what might be keeping you from getting the most out of a good night’s sleep
- uncomfortable bedroom atmosphere
- spending too much time in bed
- taking stimulants (coffee, alcohol, cigarettes, etc.) just before bed
- irregular betimes
- inactive or sedentary waking hours
- lengthy or frequent daytime naps
- taking your smartphone, laptop or tablet to bed (without a blue light filter)
- not prioritising sleep
Sleeping well requires some discipline to break all the bad habits that keep you up at night and embrace the routines and practices that help you sleep better.
Sleep is a vital self-care component that’s just as important as dieting, exercising or practising mindfulness. How you sleep directly impacts the quality of your life since it very well determines your everyday mood, performance, energy levels, social interactions and mental state. The slogan “Quality Sleep, Sound Mind, Happy World” perfectly fits today’s fast-paced world.
What should I do if I can’t sleep? It’s crucially up to you to take control of your sleep quality by observing proper sleep hygiene. If that doesn’t work, it could mean you have an undiagnosed sleeping disorder, which is nothing to be ashamed about. With the right sleep coaching, treatment, or medication, you can still claim your daily beauty sleep. Quality sleep is genuinely an easy ticket to healthy, happy living.