The amount of Snapchats and Facebook status’ I see online about students claiming to have insomnia, pulling ‘all-nighters’ and sleeping in till 5 pm is worrying. While there are a plethora of resources online from meditation apps, blogs on how to create Feng Shui in your home and sleep ‘tracking’ on our phones, we still aren’t getting enough sleep, or good quality sleep. Can you recall the last time you woke up without your phone alarm feeling refreshed and not needing caffeine?
In developing nations, two-thirds of adults fail to obtain the recommended eight hours of sleep. Inadequate sleep can compromise your health and is a key lifestyle factor which determines whether or not you will develop Alzheimer’s disease. Being a student, Alzheimer’s may not be on your mind, but poor sleep is a risk factor for depression and substance abuse and can profoundly affect memory, learning, creativity and emotional stability. The bottom line is that, the shorter you sleep, the shorter your lifespan. We are however, the only species that will deliberately deprive themselves of sleep so much that the World Health Organisation (WHO) now recognise the lack of societal sleep as a global health epidemic
Now, this is a longer blog post that I would normally write and it’s not intended to scare you by any means, but rather educate you on how sleep works, it’s importance and some tips on how you can generate better quality sleep. We don’t just sleep 25 years (on average) for the sake of it.
We’ve all been there.
How does sleep work?
Every animal species sleeps and some do more than others. When birds sleep alone, one side of the brain and the opposite eye stays awake to maintain vigilance to environmental threats and giraffes sleep on average for 4 hours. You may be asking what is the function of sleep, but there is no single answer – no organ within the body or process within the brain is not enhanced by sleep and therefore is impaired when we don’t get enough of it.
We all generate a circadian rhythm, a 24-hour clock that determines when we want to be awake and asleep and controls many functions such as body temperature, your metabolic rate, emotions and timed preferences for eating and drinking. This biological rhythm uses daylight to reset our natural clock, which lasts around 24 hours and 15 minutes in length, nearly the precise timing of the Earth’s rotation. Our body temperature peaks in the late afternoon and is another indicator that is designed to keep us awake and alert; body temperature will still peak and trough even when we are not actually asleep. Therefore, wakefulness and sleep are under the control our circadian rhythm, not the other way round. However, not everyone’s biological timing is the same – some people are naturally morning larks and night-owls, something owed to our genetics, not to our conscious.
Our circadian rhythm is communicated by our suprachiasmatic nucleus (which controls an array of behaviours, including when we want to be awake & asleep) which releases the “hormone of darkness”, that is melatonin. This chemical messenger is released into the bloodstream after dusk that acts megaphone, letting your body know it’s dark to help you regulate the timing of your sleep. However, melatonin does little on the generation of sleep, (it helps us more regulate the timing of when sleep occurs) so unless you are jet-lagged, melatonin will do very little.
The second factor that determines your sleep cycle is sleep pressure. A chemical called adenosine is building up in your brain at this very moment, the longer you are awake, the more adenosine will accumulate. This accumulation acts as a barometer which forces our desire to sleep. Caffeine blocks the receptors which activate this chemical, which masks your ability to signal sleepiness which is normally communicated to the brain by adenosine. Now I’m not saying stay away from consuming caffeine – numerous studies show that coffee can lower the risk of type 2 diabetes
and caffeine is a great pre-workout drink (and gets me out of bed most days) – but caffeine has an average half-life of 5-7 hours and many fail to realise how long it can take to overcome a dose of caffeine and subsequently fail to make the link between the cup of coffee at 6 pm and the bad night of sleep we just had. We’ve all been in the library at 11 pm with drinking cans of energy drinks trying to ‘cram’ the last block of revision in, but be wary of the ‘caffeine-crash’, your energy levels will plummet and you will find it extremely difficult to concentrate; even if you consume more caffeine you’ll start a cycle of dependency and the crash will only get worse. If you have (stupidly) committed to an ‘all-nighter’ then consume caffeine as late as you can and try to eat lots of carbs to maintain your energy levels. As a rule of thumb, I don’t consume any caffeine after 3 pm and my sleep has improved drastically, why not try this for a week?
The circadian cycle and sleep pressure are aligned: during sleep the adenosine is removed and the circadian cycle powers up until we naturally wake up. So long as you had sufficient sleep the night before, you set for a solid 16 hours of sharp brain function and the delightful sensation of being awake and energised.
Don’t be like Lorelai.
Why should we sleep?
We are constantly bombarded with information and misleading headlines on the amount of fat and sugar we consume and the amount of physical exercise we lack, but mental health and sleep rarely makes it on to our News Feed. Before I had little knowledge on why sleep is so important and now I understand how cutting yourself short of 1 hour a night for a whole week, can have discerning effects on both your mental and physical health. The lack of education has failed us to realise just how important and extraordinary sleep really is.
There are 3 stages of sleep: light NREM sleep, deep NREM sleep and REM sleep enriches a diversity of brain benefits at different times of the night; no one type of sleep is more important than the other, rather they complement each other. Sleep has proven time and time again to act as an effective memory aid; it refreshes our ability to make new memories and every night our brain is hard at work absorbing and producing new memories. We file memories to the hippocampus which is limited in its capacity to store information, and during sleep, memories are transferred to the far larger, long-term storage site of the cortex. In doing so, sleep replenishes the storage capacity of the hippocampus and the learning of new information can begin the following day. This transfer during NREM sleep, known as ‘spindles’ are especially rich during the later hours in the morning, so sleeping six hours or less and you will be depriving the brain of this restoration benefit and therefore reducing your ability to recall the information that you have learnt. We selectively choose which information to remember and forget, it not only helps us do delete irrelevant information, but it increases our processing power to access those memories we want to retain, improving the ease of memory recall.
Everyone has jumped on the fitness bandwagon, and yay to you for doing so. But, are you progressing at the rate you’d like to be? Has a recent injury taken longer to recover than expected? If you have answered yes, then you may not be sleeping enough. The term “muscle memory” is a misnomer, muscles themselves have no memory, it is in fact brain memory. Training muscles help you better execute a skilled memory routine, but the routine itself resides entirely within the brain. The more NREM sleep ‘spindles’ we have, the more we are able to improve our performance for motor skills. Usain Bolt, on many occasions, has taken naps in the hours before his races, because naps that contain these sleep slow-wave NREM ‘spindles’ offer significant motor skill memory improvements paired with a restoration of perceived energy and reduced muscle fatigue. In addition, post activity sleep helps to stimulate muscle repair, reduce inflammation and allows you to restock your glucose levels. Sleeping less than 7 hours a night will reduce your aerobic output and reduces the time to physical exhaustion.
Most people have their longest stage of REM (rapid eye movement) sleep just before waking in the morning. This stage of sleep is characterised by short-wave brain activity which mimics the activity that you experience during your waking state and your eyes move rapidly side to side while remaining closed (creepy, I know). This is when intense dreaming occurs and your brain builds connections between your stores of information which commonly seeks out the most bizarre, abstract and non-obvious associations. Many creative people report using their dreams to assist in their creative process: Salvador Dali famously connected surreal paintings to dreams and Paul McCartney’ says the melody for the song ‘Yesterday’ came to fruition after dreaming. Some believe dreams are one way our unconscious mind explores and works out problems, issues or questions that arise in our waking lives. REM sleep can help with problem-solving: A Harvard Medical School study
reported that subjects can solve 30% more anagram word puzzles when they are tested after waking up from REM sleep than non-REM sleep. The saying “sleep on it” is true as sleep and those well-needed power-naps can help us to solve difficult problems and gain wisdom, which is where we make connections among disparate ideas and facts.
Putting it all together, when we are awake we are constantly perceiving and processing information around us, in NREM sleep we reflect on our waking state, strengthening the new facts and skills we have learnt and during REM sleep this is integrated with all past experiences and information, building a more accurate picture of how the world works.
Dreaming boosts your creativity, especially if there’s a unicorn.
How can I improve my sleep?
Below are some tips on how you can improve the quality of your sleep. Consistency is key here and many of the recommendations below have helped me to fall asleep easier and wake up feeling more refreshed. I would like to point out the fact that one or two nights where you haven’t been able to get to sleep until the late hours in the morning is okay, sometimes we just have a cloudy head or we are stressed and can’t stop thinking about stuff – or more commonly because we just can’t put our phone down for more than 20 minutes. My advice is to persevere and you will achieve so much more in the long run, in your academic and personal lives and with your career.
- Having a consistent sleep schedule can make falling asleep and getting up in the morning easier. We are creatures of habit and having a routine in place can make our daily lives easier. This includes having a regular wake time which will reinforce the work of your internal sleep cycle. Sleep is not like the bank, you cannot pay off your debt at the weekend. Sleep, especially for memory consolidation is an all-or-nothing event. I’d recommend not allowing your bedtime or wake time to shift by more than an hour.
- Keep naps before 4 pm – late afternoon naps can make it harder to fall asleep at night.
- Avoid alcohol before bed, it is one of the most powerful suppressors of REM sleep. Nicotine is a stimulant which can have a similar effect as caffeine, so cut down the amount you consume before going to bed.
- Exercise can dramatically improve the quality of your sleep as it reduces stress and tires you out (and increases your total sleep time, especially deep NREM sleep). But exercising right before bed increases your body temperature making it difficult for your body to drop your core temperature to initiate sleep.
- Try not to have caffeine later on in the day, its effects can take as long as 8 hours to wear off fully. Coffee, energy drinks, tea and even some ice creams contain the stimulant.
- Give yourself some time to relax and unwind before bed, that means not setting yourself too many tasks to complete in a day. Find something you find relaxing, such as reading or listening to music and incorporate it into your bedtime ritual.
- Limit your use before bedtime with blue LED light which projects from many laptop and mobile devices, most of the time being just inches away from our retinas. Blue LED light has twice the impact on melatonin suppression than yellow light from bulbs. Most devices now let you de-saturate the level of blue LED light being emitted.
- Finally, if you find yourself still struggling to get to sleep, don’t lie in bed awake. Get up and do some relaxing activity until you feel sleepy again, the anxiety of not being able to sleep will only make it harder to fall asleep.
Thanks for reaching it this far in my blog, I know it’s very long packed with a lot of information. I hope you have finished this blog with a better understanding of why sleep is so important for us, and that you will take some of the tips away and implement them if you feel that you are struggling with getting good quality sleep. Now get an early night and test yourself on how much from this blog you can remember tomorrow, you’ll be surprised!