You sleep for 36% of your life. That’s thirty-two whole years of sleep across a lifetime, if you live until ninety. But, as a number of scientists and businesspeople are beginning to recognise, we don’t really take sleep seriously enough.
In a lecture for TED, the neuroscientist, Russell Foster, explains the historical birth of our culture’s suspicion and dismissal of sleep. Back in Shakespeare’s day, we had a different attitude towards sleep: ‘O sleep, o gentle sleep, Nature’s soft nurse’, writes Shakespeare, whilst his contemporary, Thomas Dekker, describes sleep as ‘the golden chain that ties health and our bodies together’.
From this attitude towards sleep as something intrinsically associated with our health, how could someone like Thomas Edison call sleep ‘a criminal waste of time and a heritage from our cave days’? How come, now, as Foster argues, we see sleep as almost an illness, an enemy, something that we tolerate only because we need to?
Partly to blame is the culture of productivity, starting with the Industrial Revolution, that tells us that you should be working all the time, late into the night and early in the morning. But let’s put that myth to bed: sleep is essential for your productivity, and for the rest of your life too.
The Theory: How Sleep Helps
Sleep is essential for your health, yes. But it also increases your ability to concentrate, to make decisions, to think creatively, and to interact with other people. At the same time, it regulates hormone levels, decreases rapid mood changes, and reduces stress, your tendency to anger, impulsiveness, and addiction.
These things we know as facts. However, we don’t know precisely why the body needs to sleep. As outlined by Foster – with a little help from another scientist of sleep, Dan Gartenberg – here are the main ideas as to why you just need to sleep.
The first theory suggests that, during sleep, your body and your brain repair and optimise themselves.
Think about the last time you went to the gym. The muscles you worked probably ached a little the next day, right? This is because, when you sleep, the process of muscle repair starts, through a process called protein synthesis. During sleep your body regulates a range of hormones, from those that are associated with stress, to those that control your appetite (Ever had a bad night’s sleep and been persistently hungry the next day?). Your immune system also gets a boost, cytokines released during sleep help the functioning of your immune system.
This is just some of the many positive physiological effects of sleep.
Sleep enhances brain function. Surely, you know this instinctively. How many times have you had poor concentration in a meeting because you were too tired? Or how often have you forgotten something important from only a few days before?
Sleep consolidates your memories, improves concentration, and improves your mental recall. During deep sleep your brain, miraculously, sorts and files your memories from the day, consolidating those that need to be retained for the future.
However, there is more. According to Foster, sleeping at night enhances our creativity by three times! It enhances our cognitive ability to provide novel solutions to complex problems, and it strengthens the neural connections in our brain. You are also more empathetic after a good night’s sleep: better able to register emotional cues in others, you will be more eager to help them too.
You slept like a log, or maybe like a baby. We all think we know what deep sleep means – when you’re not disturbed by anything at all and wake up feeling spot on.
Dan Gartenberg, a scientist whose research is in deep sleep, stresses the importance of deep sleep as the most restorative sleep there is. Deep sleep converts experiences into long term memories which begin to cumulatively form elements of your personality, Gartenberg explains. In this way, it really is the moment of the day when you become who you are as a person.
Deep sleep is when all the benefits of sleep are heightened – cell restoration, growth and repair, neural repair, strengthening of the immune system. However, the issue of today is that of shorter sleep patterns.
Sleep cycles pass through four stages: 1, 2, 3 (deep sleep), and REM (rapid eye movement) sleep. These stages progress cyclically from 1 through REM then begin again with stage 1. A complete sleep cycle takes an average of 90 to 110 minutes, with each stage lasting between 5 to 15 minutes. The first sleep cycles each night have relatively short REM sleeps and long periods of deep sleep but, later in the night, REM periods lengthen and deep sleep time decreases. Short amounts of sleep means less of these sleep cycles!
What, then, is a good night’s sleep?
Again, I think you probably know when you are sleep deprived. You’re grumpy, irritable, can’t concentrate, and you have great dark shadows beneath your eyes.
If you are tired in the morning, you are probably not getting enough sleep. If you snooze your alarm twice and beg for two more minutes in bed, you are probably not getting enough sleep. If you can’t open your eyes until you have had a cup of coffee, you are probably not getting enough sleep.
We are desperately sleep deprived these days. Teenagers are thought to need nine hours. Often, they only get five. Back in the 1950s, average sleep was eight hours a night. That is the average required by most adults. Now, or at least in 2013, when Foster was speaking, we get on average only 6.5 hours sleep a night. A lot of people only get five.
And how do we get one?
Your ‘circadian rhythm’, or the daily cycle that regulates your awake/sleep cycle, is calibrated by your exposure to light. If you are looking to get a good night’s sleep, you should make sure the conditions are correct for you to parallel this cycle as best as possible. In the morning, seek out the light, as this will help reset the start of your ‘awake’ period circadian rhythm.
In the evenings, create a ‘wind-down’ routine around one hour before you intent to go to sleep. No stimulating activities, that means no horror movies, stressful work, thought provoking activities that get the brain going. Keep your phone out of the bedroom (buy and alarm clock). Some people use aromatherapy oils like lavender on their pillow to help relaxation. Reduce your light exposure an hour before bed: turn off your computer, your phone, etc. as the blue light from these screens stimulates your brain.
Try not to drink caffeine after lunch because caffeine does affect the quality of your sleep (see my other article on sleep for more info).
These are just some of the things you can try to get a good nights’ kip!