How sleep works and why you need it!
Written by Benjamin Semmens, Registered Nutritionist (BHSc)
Sleep is one of, if not the most important aspect of your health! And not getting enough of it can not only affect your productivity and mood but can also increase your risk chronic health conditions such diabetes, heart disease, obesity, depression, and even early death!
Yet with modern day life, we have normalised the use of premature alarms, sleeping pills, prioritising work over sleep, and the excessive use of electronic devices that wreaks havoc on your sleep!
Sleep isn’t just a form of rest, it’s your lifeline! Without it you’ll be sacrificing living life to its fullest potential and putting both your mental and physical health at risk.
Not to mention the costs of sleep deprivation, with an estimated $66.3 billion spent each year on financial and healthcare costs in Australia. Even the environment has also suffered with many major industrial disasters attributed to sleep deprivation including Three Mile Island, Chernobyl, and the gas leak at Bhopal.
Most adults require around 7-9 hours of sleep, but many of us would struggle to get the minimum at best. Our busy work and life schedules, daily stresses, disruptive bedroom environment, and health complications can all cause us struggles to get enough sleep.
If you’re the type of person that has problems falling asleep and staying asleep, feel excessively fatigued or drowsy, wake up feeling groggy, feel the need to drink copious amounts of coffee or struggle to focus or be productive then this article is a must read!
In this blog well discuss how your sleep works, what happens if you don’t get enough sleep, and how you can take control of your sleep-wake cycles to live life to its fullest potential!
How does sleep work?
Your internal body clock aka your circadian rhythm is responsible for when you fall asleep and when you wake up. This clock works on a 24-hour cycle, for example when you wake up in the morning, your energy levels should be at their highest and as the day goes on, you’ll slowly start to become more tired until you’re so exhausted that you’ll peacefully doze off at night.
However, there are many factors that influence your sleep cycle, most importantly adenosine and light exposure.
Adenosine is a compound produced in your brain with levels increasing throughout the day that cause you to become tired. Interestingly, caffeine works to block adenosine and can explain why you feel less sleepy and more alert after your regular coffee fix, and why caffeine also disrupts your sleep! (1)
Light also plays an important role on regulating your circadian rhythm. When your eyes are exposed to light, it signals to your brain that its daytime. When the sun rises and you’re exposed to light in morning this causes a release of your stress hormone cortisol, the helps you to feel energetic and alert (for more info on stress and sleep click here). And when sun begins to set and it naturally becomes darker and your body starts to release melatonin, the hormone responsible for making you feel sleepy.
As you can probably already gather, if you don’t get enough light during the day or are getting too much artificial light at night this can have major consequences on your sleep-wake cycle. Not to mention, the effects of chronic stress that cause cortisol spikes throughout the night causing you to wake up at all sorts of weird hours.
Photo credit: https://www.liveli.com/blogs/the-wave/circadianrhythm
What are the stages of sleep?
Throughout the night you fluctuate between 4 different stages of sleep. During a typical nights rest you go through 4 to 6 sleep cycles that range anywhere from 70 to 120 minutes.
Stage 1, 2, & 3 are non-rapid eye movement (NREM) stages that are lighter stages of sleep, while stage 4, rapid eye movement (REM) stage is a deeper stage of sleep that is essential for memory, learning and creativity and where your most vivid dreams occur (2, 3).
Stage 1 (NREM): the first stage of sleep is the transition between wakefulness and sleep that typically lasts around seven minutes. In this stage your muscles relax and your heart rate, breathing, eye movements and brain waves begin to slow down. This is the lightest stage of sleep.
Stage 2 (NREM): the second stage of sleep is typically the longest of the four sleep stages and is deeper than stage 1. In this stage your heart rate, breath rate and muscles relax even more. Your body temperature decreases, brain waves become slower, and your eye movements will stop.
Stage 3 (NREM): is the stage important for making you feel alert and refreshed the following day. In this stage your heat rate, breathing and brain activity reach their lowest levels and your muscles will be the most relaxed. This stage is longer than the earlier cycles of sleep, and then decreases throughout the night.
Stage 4 (REM): This stage occurs approximately 90 minutes after you fall asleep. In REM (rapid eye movement) sleep your eyes move rapidly move back and forth (as the name suggests). Your breathing, heart rate and blood pressure begin to increase. This is the stage where most of your dreaming takes place and where your arms and legs become paralysed to prevent you from physically acting out your dreams. This stage is also where memory consolidation occurs – the process of converting recent memories into long-term memories.
In the earlier part of the night the cycles are shorter and are more NREM dominant, throughout the night the cycles gradually increase in duration with REM stage becoming more dominant until you awaken in the morning.
As you age, REM sleep becomes shorter, meaning you spend more time in NREM sleep, and why you may need more sleep as an older adult (3, 4)
How much sleep do I need?
Most adults are recommended to get 7-9 hours of sleep each night, however what’s of equal importance is your quality of sleep. If you’re waking up constantly throughout the night, this causes a disruption in your sleep cycles that can negatively impact many aspects of your health.
What happens if we don’t get enough sleep?
Sleep is essential for regulating brain function and behaviour and even short-term deprivation can affect your daily life by causing attention problems, reducing your productivity, affecting your mood, and causing fatigue.
People often become used to feeling sleep deprived thinking its normal, but long-term sleep deprivation can have serious health consequences including increasing your risk of chronic health conditions such diabetes, heart disease, obesity, depression, and early death! (5)
How to regulate your sleep-wake cycles!
One the easiest ways to hack your sleep-wake cycle is by regulating your light exposure. This can be easily achieved by getting sunlight first thing in the morning. When you get morning sunlight, it signals to your brain that its daytime and it’s time to kick some a**.
These days, it’s not realistic that we spend the whole day outside, and in truth, it’s not really necessary. Even 10 minutes of natural sunlight each morning can significantly help to wake you up.
It’s also important to continue to take regular outdoor breaks during the day that can help to keep your circadian rhythm in check by allowing the natural sustained release of cortisol during the day and in turn, the release of melatonin at night.
Now that you’ve got the day sorted, you now need to focus on what you do at night. Your eyes have blue light sensors that signal to your brain that its daytime and prevents you from feeling sleepy by blocking the production of melatonin (sleep hormone).
Both artificial light and natural sunlight emit blue light, which is great during the day, but it’s the last thing you need to be able to sleep at night. When you turn all the lights on in your home at night you are signalling to your brain that it’s still daytime (even though it’s quite clearly night-time outside) that explains why you’re sleeping patterns are all out of whack! (6, 7).
The are some simple ways to avoid this situation. Firstly, it helps if you can dim your lights as it gets darker. If you can’t dim your lights, there are alternative approaches such as wearing tinted glasses that you can purchase online that effectively block blue light.
In fact, studies have shown that tinted glasses can help your body to produce the same amount of melatonin, regardless of how bright the room is. I know, it’s a pretty radical move, but if you’re struggling to sleep and your sleep cycles are off it may be worth consideration (8, 9).
Your electronic devices also emit blue light, that’s why everyone is always telling you to avoid electronics at least an hour before bed. Let’s be honest - how many people actually do this?
We’re all guilty of scrolling on our phones or indulging in a TV show before bed. If you’re this type of person you’re in luck because there are some measures you can take to reduce blue light exposure from your electronics.
For example, there a bunch of blue light blocking apps for your phone. Your phone may already even have a ‘night mode’ already installed. If you’re worried about blue light from your computer, then you can use a program called F.lux that does the same thing for your computer.
Take-home message
If you try these methods in addition with the usual sleep hygiene suspects that can also regulate your circadian rhythm (eg. going to bed and waking up at the same time each night and avoiding caffeine and alcohol in the evenings) then you can help to get your sleep-wake cycle back on track that can help you thrive and support your body’s ability to fight disease.
If you have any questions or need support with your health, feel free to email our head nutritionist Ben at ben@13seeds.com.au
Disclaimer:
This article does not constitute medical advice and does not take into consideration your personal circumstances. Please see your medical professional before implementing the above
- https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency
- http://healthysleep.med.harvard.edu/healthy/matters/benefits-of-sleep/learning-memory
- https://www.ncbi.nlm.nih.gov/books/NBK526132/
- https://www.sleepfoundation.org/how-sleep-works/why-do-we-need-sleep
- https://www.cdc.gov/sleep/about_sleep/chronic_disease.html
- https://www.ncbi.nlm.nih.gov/pubmed/22201280
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2717723/
- https://pubmed.ncbi.nlm.nih.gov/22850476/
- http://onlinelibrary.wiley.com/doi/10.1111/j.1600-079X.2006.00332.x/full
