What do we do, as a society, when we are obliged to face uncomfortable realities that require us to make major changes to things we have grown to think of as fundamental? It is a problem we face on a global scale with the emergence of Climate Change, for example. On a personal level, there is absolutely nothing that you or I could do that would make one iota of a difference. Instead, we must look to our leadership at a governmental level. But what we demand of them is that they introduce measures that will address the problem without having any negative impact on our personal convenience. It becomes convenient to frame the issue as someone else’s fault, and it therefore becomes their obligation to get their own house in order first. And of course, nothing of substance actually gets done.
But what of other issues, where, for example, there are things that we are getting dramatically wrong on a societal basis, with disastrous consequences, but where we can each take substantive personal measures that will have an immediate individual impact on a personal level? What then? What changes would you be prepared to make to your personal lifestyle if the payoff was a major, measurable impact on virtually every aspect of your personal health and wellbeing? There is such a thing, if you are prepared to face up to it. It is called sleep.
I have just read a book called Why We Sleep – Unlocking the Power of Sleep and Dreams by Matthew Walker. If it sounds like another of those new age nostrums concocted by a self-appointed wellness guru, or, worse still, some pig-ignorant celebrity, then I must first correct that misconception. Walker has a PhD in neurophysiology, was professor of psychiatry at Harvard University, and is currently professor of neuroscience and psychology at the University of California at Berkeley where he is the founder and director of the Center for Human Sleep Science. He is recognized as one of the world’s foremost authorities on sleep, and his book has become an instant international bestseller. Walker has been invited to speak on TV shows around the world, and his April 2019 “Sleep is your Superpower” TED talk is one of the most-viewed with over a million views in the first 24 hours alone.
Walker’s book is a relatively dry and fact-based journey through the various contributions sleep makes to a person’s health and wellbeing. But, dry as it is, it makes for powerful, compelling reading. Even, to be perfectly honest, terrifying reading. What you will learn about sleep may well haunt you for the rest of your life. It should, in my humble opinion, be required reading for every man, woman, and child on the planet. Am I perhaps being a little over-dramatic? That would be a natural conclusion for you to draw. All I can say is, read the book, and form your own informed opinion. But let me share a handful of snippets with you anyway…
First of all, just how much sleep do we need, and how often do we need it? There are two major mechanisms which govern when we need to sleep. The first is a natural rhythm which has evolved at a deep level within our brains, and synchronizes with the diurnal cycle of night and day. It creates an internal clock which makes you feel tired and sleepy at night, and alert and wakeful during the day. The second is a chemical process which builds up in your brain, creating a “sleep pressure” which continues to build inexorably while you are awake, and is gradually relieved as you sleep. If you sleep a regular eight hours every night, both of those processes are in balance. However, if you stay up unnaturally late on a regular basis, even if you get up correspondingly late in the mornings, your sleep cycle will not be properly synchronized with your circadian rhythm and sleep disturbance will result. And if you pull an all-nighter then sleep pressure will build up to a point where you become dangerously drowsy, and scientific research has proven clearly that such drowsiness has effects very similar indeed to those of alcohol. A person who has been awake for 19 hours will be as cognitively impaired as a person who is a legally drunk driver.
Persons who do shift work, or who work for organizations such as the US Navy, whose sleep cycles are grossly disturbed on a regular ongoing basis, can take virtually no comfort from the fact that they have “adequate opportunities” to catch up on their requisite 8 hours of sleep. Your circadian rhythms tell your body when it must sleep, and it is when your body signals that it wants to sleep that you must sleep. A naval rating who has just completed a 16-hour tour of duty cannot simply sleep for 8 hours just because his superior officer commands it. The body will not generally respond. Even though you are dog tired, it can often take a couple of hours to unwind and actually fall asleep. The poor seaman may only get 6 hours of sleep, and that sleep will typically be of poor quality – on top of being at the wrong time.
Even if we talk about aiming for a regular 8 hours of sleep on an “optimum” schedule every day, that still does not resolve the issue completely. At different stages of life, we require different amounts of sleep. It is well known that babies and children sleep a lot more than adults, and as responsible parents we tend to provide for those developing individuals to get all the sleep they need. But at the same time it is also known that teenagers and young adults have a propensity to stay up late, and stay in bed all morning, yet we ascribe this behavior to laziness. It turns out that this is plain wrong. For reasons that remain unclear, the natural sleep cycle of youths is naturally skewed towards late nights and late mornings, and they function notably better on a whole smorgasbord of important tests when they are allowed to sleep on that natural schedule.
In America, many school boards are moving to a schedule that starts the school day at 7:30am, primarily to suit the convenience of parents and teachers. However, this practice exacts an appalling penalty on the ability of those students to learn effectively. But authorities are desperately reluctant to face up to the consequences of these facts. Even at UC Berkeley, where Dr. Walker is director of the Center for Human Sleep Science, the powers-that-be are remarkably reluctant to acknowledge this important – and now unambiguously proven – finding, let alone consider strategies to act upon it. A whole chapter in Walker’s book shines a profoundly disturbing light on the role of sleep in children and developing adults, and the way our society so thoroughly mishandles it.
Even among the adult population there is somewhat of a distribution of how the sleep cycles of individuals synch to their circadian rhythms. Some have naturally early-to-bed, early-to-rise rhythms, whereas others prefer to sleep and rise later. Unfortunately, our social norms have become strongly skewed towards the former, with breakfast-meeting types being seen as proactive, industrious, and strong leaders, whereas natural late risers are seen as lazy, unreliable and unworthy. It turns out that these stereotypes are entirely without foundation, but extreme societal pressure forces the latter types to adopt the behavior patterns of the former, to their dramatic detriment.
What are these dramatic detriments? A better question might be what aren’t they? Let me list a few of them, in no particular order.
- Memory and learning. Sleep plays a critical role in transitioning recently-acquired information from short-term to long-term memory, functions which take place in very different regions of the brain.
- Weight gain. Sleep loss causes the build-up of a hormone that signals hungriness, while at the same time suppressing a companion hormone that signals satiety.
- Tests on mice show truly terrible links between sleep deprivation and cancer. Not only are sleep-deprived mice more likely to develop tumors when exposed to triggering carcinogens, those tumors turn out to be significantly more aggressive.
- Blood sugar. Inadequate sleep disrupts blood sugar to such a profound degree as to classify a person as pre-diabetic.
- Alzheimer’s disease. Some early research on the development of Alzheimer’s is showing what look like clear links between inadequate sleep and the propensity to develop this unpleasant disease.
- A certain part of our DNA is made up of structures called “telomeres”. Long strings of telomeres are found at the ends of the DNA sequences known as chromosomes, and form a kind of protective cap. It is not known what telomeres actually do, but a gradual loss of telomeres are a significant aspect of aging. And – wouldn’t you know it – the less sleep a person obtains, the more damaged are the capping telomeres of that person’s chromosomes.
- Drowsy driving is a major cause of traffic accidents. In fact, vehicle accidents caused by drowsy driving exceed those caused by alcohol and drugs combined. Furthermore, the inherent nature of drowsy-driving impairment (something Walker covers in great detail) means that those accidents actually tend to be far more deadly.
Walker’s book presents these – and more – not as mere headline-grabbing sound bites. He goes into each one in scientific detail, citing researchers, data and hard numbers, and providing context and counterpoint. It is one of the disappointing aspects of Western culture, its societal values, and indeed its approach to hard science, that we tend to want to reduce critical issues to black and white positions. For example, butter has for fifty years been seen as a BAD THING, a fundamentally unhealthy foodstuff, whereas the reality is quite different, and the product developed to replace it – margarine – is in fact considerably worse for your health. Thus it is with sleep. Mankind has never fully understood the need for sleep. Why we sleep, what happens when we sleep, what doesn’t happen when we don’t sleep…these are questions to which, until now, we have had no detailed answers. And our response to such matters is generally that if we don’t understand something we conclude that it can’t be all that important. Clearly, this has been doing us a great disservice.
As you can tell, this book has made a most profound impression on me. I gave copies to my son and daughter, and feel like I should be recommending it with almost evangelical fervor to anybody else who wants to listen to me.
Or read me.