Stop promoting sleep deprivation

Even 1.3–1.5 hours of reduced sleep for one night can reduce your alertness throughout the day by 32%.

Image by Oldiefan from Pixabay

You should not look up to individuals labelled “sleepless elite” as role models for success in life. The invention of alarm clocks and the increase of cultural and societal demands and influences (e.g. workload, media promoting unhealthy sleep schedules, etc) have unconsciously converted us over the years into sleep deprived beings, wondering why we don’t feel fully functional. You may say — “but, I feel fine”, or “I may feel tired for a day or two, but afterwards I am fine” — and dismiss it. But that’s actually not the right way to think about it.

Instead, think about it like any other long-term investment you make in life. For instance, when it comes to your pension, you tend to save a certain amount each year to reap the benefits when you get older. Those early savings might appear insignificant at that moment, but in the long-run you could end up with a notable amount waiting for you. Similarly, with sleep, by acquiring sleep debt (i.e. the cumulative effect of not getting enough sleep) over time, you might not realise it, or bother by its effects in the short-run, but in the long-run, especially when you are older, it can present itself as a significant, negative investment on your mental and physical wellbeing.

In this article…

• You will learn about the crucial physiological and psychological aspects of sleep and its relation to (1) human cognition, (2) emotion regulation, (3) food cravings and obesity. There are many more aspects that can be affected by sleep but there is only so much that can be covered in a single article before getting tedious.
• You will learn about healthy sleep patterns and tips you can use, and be warned against sleep-deprived practices, which are detrimental to your health!

Our society has not grasped the dangers of sleep deprivation, stereotyping sleep behaviour as a time-wasting and lazy attitude.

The mere fact that all bedrooms have an alarm clock nowadays, implies that in today’s society, from children to adults, we all suffer from sleep deprivation, some more than others [1]–[3]. Even 1.3–1.5 hours of reduced sleep for one night can reduce your alertness throughout the day by 32% [4].

The act of sleeping itself is a universal necessity [1], [5], [6]. As human beings, specifically, we spend one third of our lives sleeping; this means that on average, over your lifespan, you will have spent a total of 20–30 years being asleep [7], [8].

Nowadays, researchers and health experts understand enough about sleep to know that it contributes to our survival, and the healthy functioning of our mind and body, and it is as critical for our good health as nutrition and exercise [7], [9]. Healthy sleep is a combination of adequate sleep duration, good sleep quality, consistent timing during the day and absence of sleep disorders, which means that even a tendency towards excessive sleep is not ideal as it might indicate signs of poor sleep quality [9]. Despite that, our society has not grasped the dangers of sleep deprivation, stereotyping sleep behaviour as a time-wasting and lazy attitude, and promoting a decrease in sleep duration [1], [2].

Healthy sleep is a combination of adequate sleep duration, good sleep quality, consistent timing during the day and absence of sleep disorders.

1. Sleep affects your learning, and the plasticity of the brain (i.e. the brain’s ability to modify itself as you develop from a baby to an adult)

Having difficulties concentrating after a bad night’s sleep?

Sleep contributes to the healthy balance of the activities that happen in your brain and body, such as blood pressure and hormonal balance. For example, research looking at REM sleep-deprived rats throughout their lifespan showed that they suffered from a variety of symptoms similar to depression [11]. Extreme lack of sleep can even cause death, that is how crucial sleep is considered for your body and mind to develop and function properly [12].

Individuals up to the age of 17 years old showed a positive link between memory consolidation, and taking naps, along with a good night’s sleep after learning, compared to those who did not take any naps.

Sleep quality is also significant for ongoing brain development in later life. For instance, it is suggested that lack of sleep in teenagers negatively affects grey matter volume and the size of various parts of the brain [13]. Sleep deprivation also negatively affects the formation and consolidation of neural links in the brain, which form neural networks that are critical for memory processing and retrieval. For example, sleep deprivation has been shown to directly affect the function of the hippocampus, a part of the brain playing a big role in the consolidation of learnt knowledge [14]. Individuals up to the age of 17 years old showed a positive link between memory consolidation, and taking naps, along with a good night’s sleep after learning, compared to those who did not take any naps [15].

Sleep quality is also significant for ongoing brain development in later life.

The US National Sleep Foundation has recommended for peak performance and health, 8–10 hours of sleep for teenagers up to the age of 17, 7–9 hours for adults and 7–8 hours for older adults [9], [16]. It is not entirely clear why older adults ‘need’ less sleep. Some scientists hypothesise that while good quality sleep is still necessary to minimise decay in cognitive ability, from a duration point of view older adults might not require as much sleep as their younger counterparts, due to reduced demand on brain development [17], [18]. However, others have suggested that instead of sleep needs decreasing over time, the reduced duration of sleep may instead reflect an impaired ability in older age to regulate sleep effectively in order to meet those needs [18].

Sleep patterns can vary per individual depending on genetic, behavioural, environmental and social factors, but as a general guideline, health experts and researchers advise towards a sleep duration of 8–10 hrs for teenagers, 7–9 hrs for adults and 7–8 hrs for older adults.

Additionally, having a routine and a sleep schedule is important, especially if you are suffering from sleep disorders. To help you wind down and sleep better the NHS suggests to: (1) avoid watching TV and using smartphones, tablets, and other electronic devices at least an hour before betime, (2) do light stretching exercises if you need help winding down, or take a warm bath, (3) keep a sleep diary to identify what might be causing you sleeplessness, and (4) convert your bedroom into a relaxing and sleep-friendly environment.

2. Sleep affects your emotion regulation and social awareness

Are you in a bad mood, or feeling stressed after a bad night’s sleep?

Sleep deprivation affects various brain areas including the prefrontal cortex which is responsible amongst others, for organising your mental processes and regulating your emotions [19]. A longitudinal study, examined the link between sleep deprivation and parenting through physiological measurements, home visits and questionnaires [20]. The findings presented significant bi-directional links between sleep deprivation and stress. A bad night’s sleep was associated with increased cortisol and cholesterol levels, seen in stressed mothers. Increased levels remained high throughout the day and in combination with other parenting tasks, not allowing mothers to get a good night’s sleep the following nights. The combination of those patterns was accompanied by a reduction in normal physiological values measured in the prefrontal cortex, and the participants continued having increased negative emotions and low tolerance to otherwise small stressors.

A bad night’s sleep was associated with increased cortisol and cholesterol levels, seen in stressed mothers.

The effects on the prefrontal cortex are not just about your wellbeing and that of others around you, but they are also crucial for your survival. For instance, daily life can include many situations where you might need to judge another individual’s disposition or intent, and where misjudging could have serious repercussions; for instance, what if you had misinterpreted the intentions of a stranger approaching you — mistaking friendly as malicious, or vice versa — or misinterpreted a colleague’s tone of voice as condescending when they were trying to be considerate. Even a single night of sleep-deprivation can affect the accurate recognition of others’ facial expressions [21]. Specifically, sleep-deprived, but otherwise healthy individuals, have been shown to do worse at recognising the emotions of happy and angry faces, compared to those who had adequate sleep. In other situations, such as the examples mentioned above, sleep deprivation may lead to misjudgement of social threat [22], [23].

Even a single night of sleep-deprivation can affect the accurate recognition of others’ facial expressions, such as happy or angry faces.

3. Sleep affects your food cravings and obesity

It is no coincidence that staying late at night makes us crave fatty and unhealthy food such as sugary treats or KFC!

A systematic review and meta-analysis on 45 cross-sectional studies found high significance between low sleep duration and higher obesity levels in adults and children [24]. Sleep duration, BMI measurements and demographics were taken into consideration for more than half a million participants, of which the vast majority were adults. In agreement with various other studies [19], [25]–[27], the link between lack of sleep and increased obesity risk was mostly made in relation to affected hormones (e.g. dopamine) and a sedentary lifestyle. However, the question of which particular hormones are affected, how significant lack of sleep is in contributing to their imbalance, and whether there are other unaccounted factors such as varied dietary and fitness lifestyles, have been the subject of considerable debate.

The main neurotransmitter of our brain’s reward system is dopamine. When you eat a delicious chocolate cake and feel ecstatic about it, this is because of the dopamine hormone being triggered to make you feel rewarded. Dopamine seems to be quite sensitive to our sleep patterns, becoming over-sensitised by lack of sleep due to our wakefulness not allowing our body to properly regulate our hormones [19]. Over-sensitised dopamine tends to lead to cravings of foods high in fat and sugar, a fairly unhealthy diet, which combined with the timing of our sleeplessness — usually late at night when we are pretty much sedentary and inactive — increases our risk of obesity. Other hormones affected by lack of sleep include increased levels of ghrelin, which is secreted by the stomach to alert us we are hungry and have to eat, and reduced levels of leptin, which is responsible for converting fat into energy [27]. With the combination of all those three hormonal imbalances, it is no wonder that lack of sleep is linked with increased risk for obesity.

This is a nice video, briefly going through the importance of sleep.

Concluding remarks and helpful tips

All this evidence makes for a compelling argument for why sleep quality and duration should be a foremost concern for individuals, parents, schools, the workplace, and society in general.

There are still many aspects regarding the importance of sleep and its effects on the brain and body, that remain a mystery. However, the studies mentioned here offer a good foundation that could contribute in educating our society on the benefits of sleep and reinforce its importance on our overall wellbeing. Sleep is universal, and more and more evidence is coming in every day that it affects all aspects of our life, from behaviour, to memory, and even how we eat.

All this evidence makes for a compelling argument for why sleep quality and duration should be a foremost concern for individuals, parents, schools, the workplace, and society in general. A fundamental shift in mentality is therefore needed: our society needs to stop treating healthy sleeping attitudes as the product of lazy minds. It should instead strive to promote them as a fundamental natural requirement, and the right thing to be doing, in order to preserve healthy bodies, healthy minds, and ultimately healthy societies.

This change, towards healthy sleep patterns, can start with you! You can be an advocate by sharing this article, and helping others understand the importance of sleep through your positive example from now on. Personally, I tend to do two things to help get me into a bedtime mood:

1. I tend to keep all the lights in the house switched off in the evening, apart from a table lamp or two, to help notify my internal clock it is getting close to bedtime.
2. I usually set an alarm clock about an hour before bedtime to remind me that it’s time to start my night-schedule (e.g. brush teeth, write down my family’s meal plan for the following day, get into bed and read or play sudoku for a bit), which gives me some sense of control. I don’t get into bed before then.

You could work on embedding such a routine into your daily schedule too, to form healthy habits —having a routine is important to help keep you on track! However, if you find it difficult to stick to a routine, remember you can always try the advice offered by the NHS.

Note from the author…

If you found this article helpful or interesting, recommend it and share it, so others can benefit from it too! 😊

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‘A Cup of Psyence’ is a collection of essays on human psychology, science, user experience (UX), technology, and general wellbeing — curated by C. Maltezou-Papastylianou, with the occasional invited article by other experts.

References

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