When Shakespeare’s Macbeth has just committed the ungodly act of regicide, he is wracked with guilt, unable to sleep. “Balm of hurt minds,” he laments “Great nature’s second course,
Chief nourisher in life’s feast.” Both he and his wife never have a good night sleep ever again; she loses her mind in her restless sleepwalking, and he becomes emotionally numb to his situation, before losing a battle in dramatic fashion. With a good night’s sleep under his belt? Who knows how it might have ended.
As usual, Shakespeare was on to something here. It is only 400 years later that we have begun to truly understand why sleep matters, and what happens to us if we aren’t getting enough.
In short, it is fatal.
This isn’t even hyperbolic. Dr. Matthew Walker is a neuroscientist who specialises in sleep, or as he calls it, “the elixir of life. It is the most widely available and democratic powerful healthcare system I could ever possibly imagine.” Today, I am going to step you through his research, and I promise you one thing: This will genuinely blow your mind. You will never look at sleep the same way again.
Firstly, a lack of sleep affects your physical performance. Studies have shown that the time to physical exhaustion drops up to 30% if you’ve had less than six hours sleep the night before. Let’s say you want to run 10km around your local lake, and you usually finish that run with nothing left in the tank. With less sleep, you will only get to 7km before you need to stop. That is a pretty significant drop in performance. Essentially, you build up lactic acid in your muscles much quicker when you’re sleep deprived. This is the thing that ‘burns’ when you exercise, and makes you slow down. But it doesn’t stop at cardio. A lack of sleep also lowers your muscular strength, vertical jump height and sprint speed.
You are also much more likely to sustain an injury during physical exercise if you haven’t had enough sleep, and not for the reasons you think. You might expect that a sleep deprived person might lose focus and roll their ankle. But in actual fact, your muscles are more likely to tear in normal movement without a good night’s sleep. The muscles which stabilise your movement give way much earlier. Studies have shown a 60% increase in injury between people who had nine hours of sleep, and another group who had only had five hours.
Secondly, you are much less capable intellectually when not getting enough sleep. According to Dr Walker, if you go a fortnight with six hours or less of sleep, your intellectual capacity begins to decline, and doesn’t level off. Hypothetically, you could degenerate so far that you cease to be you anymore. The first thing that switches off in our brains when deprived of sleep is our prefrontal cortex. This regulates our emotional reactions, so it is pretty easy to see how we can become less rational and reasonable. The solution is pretty simple: more time in the land of nod!
Thirdly, and perhaps most importantly, the fewer hours you sleep in a night, the fewer years you will live. Being awake actually causes low level brain damage, which is usually repaired during the hours in bed. When we don’t get that balance right, there is no repair mechanism. Dr Walker describes the way that sleep is like a sewerage system that cleanses the brain of all the metabolic toxins which accumulate during the day. What kind of toxins you ask? Well, one you might want to keep an eye on is called beta amyloid. This is one of the early catalysts of Azlheimer’s disease.
A lack of sleep is also linked to various cancers: bowel, breast and prostate to name but a few. How do we know this? There are much higher instances of these cancers (as well as diabetes) in shift workers, and the only correlation between them is their inconsistent sleep hours. In fact, the World Health Organisation has moved to list shift work as a probable carcinogen.
Part of the reason for this is that when we get hungrier awake than we do asleep. So the more hours you spend awake, the more food you will consume. But it is worse than this. A sleep deprived brain loses the capacity to determine when it is full. We have two hormones which regulate appetite: leptin and ghrelin. When we get less than the recommended hours of sleep, the brain suppresses leptin (which tells us we are full) and ramps up the production of ghrelin (which makes us hungry). Studies have shown that people who sleep five hours a night will eat about 1200 kilojules more than a person who gets a full night. That equates to a cheeseburger a day. Now that might not sound like much, but think about eating seven cheeseburgers every week on top of your existing diet? All of a sudden it is starting to add up.
So you might have the fear of God put into you, but all that anxiety is gonna keep you awake. I need to fall asleep ASAP or will develop every illness under the sun. That is hardly an ideal way to nod off. When I have customers come to me complaining of difficulty getting to sleep, I will often point them towards Swisse sleep supplements. Swisse sleep includes natural ingredients that help you become calm and restful in the lead up to bed time: magnesium, and valerian. I want to make one thing clear. There is NO medicine that you can take to make up for not sleeping. You need to make some lifestyle adjustments if you are not regularly getting between seven and nine hours sleep every night. But Swisse Sleep is a great way to prepare you so that when you’ve hit the hay, you don’t spend too much time lying awake stressing.