When I first started thinking about this blog, I was going to entitle it “Five Reasons to Sleep” and then discuss five benefits of a good night’s sleep. However, when I started to think about it, I realised that there is really only one reason to sleep: to keep alive!
Every single creature on earth sleeps. Even your goldfish sleeps. Even the worm in your garden sleeps! And without sleep, life dies. In the 1980s a study was conducted on the effects of sleep-deprivation on rats. Ten of these rats were totally sleep-deprived. All of them died within 11-32 days. In addition, these rats lost weight despite an increase in food, developed sores on their tails and paws and became progressively debilitated.
Sleep deprivation and chronic disease
According to sleep specialist Matthew Walker, human studies have shown that chronic sleep deprivation is associated with higher risks of developing cancer, diabetes mellitus type II, cardiovascular disease, Alzheimer’s, depression, anxiety and suicide. He also points out that more people die in car accidents caused by fatigue than accidents caused by alcohol and drugs combined.
“Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer”.Matthew Walker
The mystery of sleep
Interestingly, although people have been studying the concept of sleep for thousands of years, it was only in the 20th century, with the invention of the EEG machine that we were able to start answering the question of why we sleep. Before this, the reason for sleep was a mystery – a mystery with many different ‘explanations’.
Aristotle, for example, believed that when sleeping we were actually being ‘gassed’ by the vapours from food while it decomposed in our stomachs. Eighteenth century scientists, on the other hand, proposed that every night blood would rise up into our heads, causing our brains to temporarily shut down and induce sleep.
In terms of evolution and survival of the fittest, the concept of sleep was almost non-sensical before we began to unravel the physiological value of sleep. Think about it: for nearly a third of our day we are in a completely vulnerable state – lying down, our eyes closed, many of our muscles ‘paralysed’, many of our senses that usually keep us safe from danger ‘dampened’ – we are like sitting ducks to all sorts of predators!
Why do we sleep?
So, you may be asking, “why do we sleep?”. Believe it or not, this question still cannot be fully answered but research is progressing in this area and we are learning that sleep is not simply a means to conserve energy as we once thought.
In fact, we now know that we actually save very little energy during sleep. According to sleep expert Chris Idzikowski, “a person weighing 200 pounds (approximately 91kg) burns off calories during sleep at a rate of 80 per hour. The same person sitting quietly uses up calories at a rate of 95 per hour”. That’s only a difference of 15 calories – not much!
“The energy saving during eight hours sleep (compared with eight hours waking rest) is roughly equivalent to a glass of low fat milk”.Chris Idzikowski
Although our bodies might be at rest during sleep, our brains are extremely active. Sleep is the time in which:
- The brain ‘cleans’ and restores itself.
- The hormone (human growth hormone) that stimulates muscle and bone growth as well as fat metabolism is secreted.
- Our immune system actively seeks out and destroys foreign cells.
- We create and consolidate memories.
- We make creative connections.
So I guess instead of focusing on five different reasons to get a good night’s sleep, we really only need to focus on one: if you don’t prioritise your sleep you may not only end up looking like Frankenstein – you might end up becoming him too!
Health matters. So join us.
Carol A. Everson, Bernard M. Bergmann, Allan Rechtschaffen, Sleep Deprivation in the Rat: III. Total Sleep Deprivation, Sleep, Volume 12, Issue 1, January 1989, Pages 13–21, https://doi.org/10.1093/sleep/12.1.13
Chris Idzikowski, Learn to Sleep Well (2000), Duncan Baird Publishers: London
Matthew Walker, Why We Sleep: The New Science of Sleep and Dreams (2017), Scribner: New York