The Hidden Power Of Your Sleep
A year ago I was a person like many others today, who thought nothing in particular about sleep apart from the fact that I knew we needed it. I did not prioritize my sleep nor did I take care of it, because I simply thought that sleep only had one function - to “recharge our batteries”, whatever that meant. Until about three months ago, I did not put much attention towards my sleep quality or quantity but that all changed when I read the book “Why we sleep” by Mathew Walker.
By reading the book I was shocked to find out how much research was emerging in the field of sleep and showing not only the importance and the myriad of biological and psychological functions that sleep plays in or bodies, but also daily actions and activities that on a long term basis, seriously hinder our sleeping patterns, leading to irreversible damage. It is estimated that in the United States alone, roughly 35% of adults report sleeping less than 7 hours per night and studies across the United States have concluded that 50-70 million US citizens have a sleep disorder, Insomnia being the main one.
Taking care of your sleep might just single-handedly be the mos timprotant thing you can do for your long term health. From improving your energy levels, mood and concentration to keeping your immunity and brain healthy, sleep is the last thing you want to be neglecting.
PHASES OF SLEEP
The science behind how we sleep is actually quite complex and more detailed than you might think, however here I have split it up into four basic sections of “sleep cycles”, in order to illustrate the phases we go through in our sleep and the individual roles that each of them plays for our health.
NREM SLEEP
The first stage of sleep we encounter is NREM sleep which is Non-Rapid Eye Movement sleep. This stage is split into three sub-stages, as described below:
STAGE 1: RIght after we fall asleep, we fall into stage one of NREM sleep, which is where our brain experiences alpha waves that have a frequency of 8-12 Hz. This initial stage os very short, often being less than 10minutes long and during this stage, you can still easily be wakened up.
STAGE 2: The second stage of NREM sleep is longer than the first one, ranging from 20-60 minutes and is predominantly the time where our brains go through theta waves that have a frequency range of 3.5-7.5 Hz. In this stage, your body begins entering a deeper stage of sleep where your muscles start relaxing, your body temperature decreases and your brains starts producing “sleep spindles”, which are in simple terms, short periods of quick but rhythmic brain wave activity that happens between frequencies of 12-15 Hz. Sleep spindles have been shown to be a critical component of memory consolidation, a topic which will be discussed more later.
STAGE 3: The last stage of NREM sleep, also known as “deep sleep”, is a stage that lasts between 20-40 minutes and in this stage, there is a large increase in brain delta activity where we may experience some unconscious movements of our muscles. on the other hand, this stage is where our muscles are fully relaxed, we have a drop in body temperature, blood pressure and breathing rate, all of which makes it very hard to wake someone up in this stage of sleep. lastly, the stage of deep sleep is responsible for restoring our energy levels, repairing our cells and regenerating our muscle tissue which is needed for growth and repair.
REM SLEEP (STAGE 4)
The stage of REM sleep is known as the Rapid Eye Movement stage, where a couple of critical changes take place; First, our eyes and eyelids begin to move and flutter and neural activity in our brain increases.. Secondly our breathing patterns change and become more irregular. lastly, this is the stage where we may experience dreams and our muscles have become so relaxedly that they become immobilised and in other words, our body is temporarily paralyzed.
ABOUT OUR SLEEP CYCLES
During a single night, we will first enter all stage of NREM sleep and then transfer into REM sleep. It takes us about 1-2 hours to first enter REM sleep and after that, the whole cycle starts again so that we repeat the same cycle 3-4 times in a single night. The differences between the cycles are that our first REM sleep stage will be very short and will gradually get longer as we progress through our sleep cycles.
This highlights an important point: In order to experience the benefits of sleep, most of which come from a adequate time spent in REM stage sleep, we have to spend a decent portion of our night in good quality sleep to allow us to progress through all the sleep stages and obtain enough NREM and REM sleep for a single night.
Just relying on NREM sleep is not enough, we need both sleep phases for optimal performance.
COMMON SLEEP DISRUPTORS
BRIGHT LIGHT EXPOSURE
Numerous studies, again and again, have shown that exposure to bright lights or to LED screens from our devices, considerably delays the release of the main sleep-inducing hormone, melatonin. This is because, in the retinas of our eyes, we have specialised photosensitive cells that are able to tell our body whether it is day time or night time and set our sleeping patterns accordingly.
Therefore it is advised to keep digital screens limited or restricted before one hour of your bedtime, to ensure a well-rested night. concerning other lights, it is preferred to dim down bright lights and switch to warmer tones instead of blue-toned lights.
STRESS, ANXIETY AND PAIN
If we are stressed or anxious, our body is in a state of hyperarousal where we experience the inability to calm down with an increased pulse and body temperature - both of which prevent us from sleeping. Furthermore, if we start to worry and think about the fact that we are stressed and can’t sleep, that generates more stress for us, making it additionally harder for us to sleep properly.
Before you head to bed, it is advised to destress and get rid of any worrying or sleep-disrupting thoughts that would otherwise persist through the night.
LOUD NOISES
It is no doubt that loud noises can be disrupting to our sleeping patterns, and researchers have proven that loud sounds are much more likely to wake us up from the first two stages of our sleep compared to the last stages, where we are in a state of deep sleep. Interestingly enough, we are also much more likely to respond or get woken up by a sound if we have a specific emotional attachment to it, such as if we hear someone crying or getting hurt.
If you can hear the sounds of outdoor traffic or city life, try sleeping with ear plugs or better sound-insulating windows. In the case that the sound still persists, try some of the other sleep-inducing methods that are mentioned at the end of this article, to ease you into a sleep state.
IMPROPER TEMPERATURE
In order for us to enter into a sleep state, one of the factors that has to change in our body is our core body temperature has to lower. In fact, a temperature of about 18 degrees Celcius (65 degrees Fahrenheit), has been shown to be the best temperature to sleep in since it is neither too warm nor too cold.
To help cool down our body, as counter-intuitive as it may sound, we can try wearing warm clothing such as socks which will dilate our surface blood vessels, so that more heat is able to escape out and cool down our body.
MEDICATION
Often, drugs that are used to treat cardiovascular issues and high blood pressure can impact our sleep by causing sleeplessness and being more prone to experiencing nightmares. Furthermore, the same consequences have also been attributed to using antidepressant and thyroid medications.
On the other hand, we also have a class of drugs called stimulants, that include ADHD medication, asthma medication and certain pain killers most of which contain caffeine compounds, that keep us awake and alert.
EATING AND DRINKING TOO LATE
If we regularly eat too late, it can result in us having stomach acid reflux, also know as heartburn, or we either can experience stomach pains that cause us to not be able to fall asleep. Also, we ave to be mindful of how much water we consume right before sleep as otherwise, we can take frequent bathroom trips during the night, that undoubtedly disrupt our sleep.
Apart from eating and water, we have to also be very wary of our caffeine intake. Caffeine, as mentioned before, is a stimulant that has been shown to decrease both our sleep quality and quantity. Furthermore, caffeine has a half-life of 3-5 hours, which is the time taken for our body to eliminate hold of the drug in our system, which as a result means that in order to get rid of all of the caffeine in our body, it can take up to 6-10 hours.
lastly, alcohol consumption before bed has also been extensively researched and has been shown to have profound impacts on our sleep. While drinking alcohol right before bed has been shown to create more delta brain activity that is usually associated with deep sleep, it also promotes the simultaneous production of alpha brain wave activity that happens in the first stage of entering sleep. These two different wave frequencies undoubtedly conflict each other and create sleep disturbances.
Furthermore, alcohol consumption has been linked with releasing a chemical called adenosine that has sleep-inducing properties and then leading to a quick decline in adenosine levels throughout the night, which explains why we initially find it easy to fall asleep but then can experience multiple awakenings during the night.
Alcohol has also been shown to block the stage of REM sleep, which is a crucially important phase of our sleep that is responsible for cellular regeneration and memory consolidation.
EXERCISING LATE
While exercise is definitely a positive factor for our health, vigorous exercise done between 1-2 hours of our bedtime has been shown to disrupt our sleep and make it harder to fall asleep because during exercise our core body temperature and pulse are raised as well as our nervous system being more stimulated, which makes it much harder for us to initiate sleep.
SLEEP CONDITIONS
INSOMNIA
This is the most common sleep disorder, where the person either can not fall asleep or has trouble staying asleep for longe periods of time. Insomnia comes in two different forms: acute or chronic, where acute insomnia is experiencing insomnia on an occasional basis, but chronic insomnia is where you repeatedly find it hard to sleep, causing great long term health setbacks.
Some of the main causes of insomnia include stress, travel (which disrupts our natural circadian rhythm), having poor sleep habits, taking sleep affecting medications and the consumption of alcohol before bed.
The magnitude of the consequences depends on how extensive the insomnia is and how much it impacts our sleep, but long term chronic insomnia can seriously hinder our performance, focus and productivity during the day, where we experience less creativity and have been shown to have slower reaction times. Furthermore, insomnia and inadequate sleep both in quality and quantity have been linked with a greater risk for mental conditions such as depression and chronic health conditions like elevated blood pressure and heart disease.
SLEEP APNEA
Sleep apnea is a sleeping disorder that comes in three different forms and causes you to briefly stop breathing during the night, before starting to breathe again. Often these disruption in breathing are minor and we don't even notice them but they do cause sleep interruptions.
Types of sleep apnea:
Obstructive sleep apnea: This is the most common form of sleep apnea and it is where our through muscles relax during our sleep, causing a brief inability to breathe that can lead to us waking up or snoring.
Central sleep apnea: This type occurs when your brain does not send proper brain signals to the muscles that control breathing mechanisms in our body.
Complex sleep apnea syndrome: This is a more rare case, but it is where we experience both obstructive sleep apnea and central sleep apnea.
The consequences of long term sleep apnea include fatigue during the day, a higher blood pressure, type II diabetes and having more liver functioning abnormalities.
NARCOLEPSY
This is a chronic sleeping disorder where we constantly feel tired and exhausted during our days, which causes us to experience sudden attacks of sleep or naps, making it hard to stay awake for long periods of time, independent of the circumstances we are in.
The causes of narcolepsy are so far unclear, however, the consequences are severe where a person suffering from narcolepsy will experience more mental fogginess, and impaired memory, hallucinations during the day and finding it harder to learn. Furthermore, the person's social life can seriously be impacted, as sleep can disrupt social events and plans unintentionally.
FUNCTIONS OF SLEEP
The functions of sleep for our well being are many and they explain just why sleep is so important for us.
Firstly, several studies have linked adequate sleep levels with improved mental cognition, in the form of improved memory, better concentration, a faster learning rate and more neuroplasticity, which is defined as the ability of our brain to reorganize itself by forming new neural connections. Furthermore, if we sleep enough and have good quality sleep, we have better decision making, problems solving, controlling our emotions and enhance our ability to cope with change. lastly, being chronically sleep deprived increases our chances for developing depression, suicide risk and risk-taking behaviour that encourages more accidents.
The reason why so many studies link sleep with better memory is that sleep has been shown to be responsible for memory consolidation, where our short term memories are transformed into our long term memory, and as a result, we are able to learn and eventually retrieve more information when we need it.
Another function of sleep is to get rid of all of toxins and waste products that accumulate in our brains during the day, which would otherwise pile up and could over time causes serious cognitive decline and inability to concentrate. In infants, sleep plays an especially critical role where it is responsible for the growth and maturation of their brain.
For our body, sleep has functions such as repairing and restoring our cells and tissues in our body, which is largely connected with our cardiovascular and respiratory health. Undoubtedly, sleep also has a big role in promoting growth and development of our organs, cells and tissues, because during sleep our body secretes growth hormone that is responsible for initiating cell growth.
Apart from regulating the growth hormone, sleep also regulates plenty of other hormones such as the hunger and satiety hormones; ghrelin and leptin, as well as the blood sugar controlling hormone insulin and the working of our sex hormones.
CONSEQUENCES OF SLEEP DEPRIVATION
Because sleep plays so many functions for our body and is so vitally important for our functioning if we skip on our sleep or experience regular poor quality sleep, we have the risk of developing a plethora of health issues. Of course, one night of bad sleep is only a short term issue, but the issue arises when we experience repeated sleep loss that then over time accumulates to form larger health issues.
BRAIN HEALTH
Foremostly, continual poor sleep quality has to no surprise been linked with a decline in our general cognition, where we find it harder to focus, concentrate and just generally be productive with our time. Furthermore, we find we have more impaired memory, lower levels of creativity and experience more mood shifts during the day that can lead to poor decision making and irrationality. Because we have poorer focus and worse decision making, we have a slower reaction rate that greatly increases our risk of accidents, which can often result in an unnecessary loss of life, such as in car accidents.
CHANGES IN HORMONE LEVELS
Since our brain is weakened, we experience changes in hormone secretions that are ultimately responsible for influencing or initiating almost any biochemical reaction within our body. For example, the production of sex hormones drops, which leads to a lower sex drive and we experience a decline in our growth hormone levels that are is otherwise responsible for the repair and growth of cells and muscles, so our tissues heal and repair themselves slower.
WEIGHT REGULATION
Sleep has also been shown to have an impact on our weight, as it is responsible for controlling the hormone ghrelin and leptin that provide our body with hunger and satiety cues. With inadequate sleep, it has been shown that we have higher levels of the hunger hormone ghrelin and lower levels of the satiety hormone leptin, which is why we are more prone to snack during the night and thus overeat, which can over time result in unwanted weight gain. Apart from that, if we get less sleep than necessary, it has been shown that we suffer from lower insulin levels, where insulin is the hormone responsible for lowering the concentration of blood sugar in your blood, therefore with less insulin, you become more insulin resistant as you always have more blood sugar in your bloodstream, which ultimately raises your chances of developing type II diabetes.
CARDIOVASCULAR CONDITIONS
In terms of other chronic health conditions, sleep deprivation has been linked with a greater risk of having cardiovascular issues for a couple of compelling reasons. Foremost, sleep deprivation has been linked with impaired healing and regeneration of cells, blood vessels and heart tissues as well as being involved in processes that regulate sugar, blood pressure and inflammation levels, all of which raises our chances of heart disease.
RESPIRATORY ISSUES
In terms of our respiratory health, poor sleep has been correlated with more instances of the sleeping disorder Obstructive Sleep Apnea, which undeniably can have a negative impact on our sleeping patterns.
WEAKENED IMMUNE SYSTEM
inadequate sleep mainly impacts your immune system in two primary ways: The first one being that your bodies production of specialized proteins that fight infections of inflammations in our body, called cytokines, is reduced, meaning that we have a harder time healing and have more instances of long term infections. Secondly, if you are sleep deprived, it has been shown to lower the amount of infection-fighting antibodies and cells in your system, which leaves you more prone to becoming sick.
POORER SKIN HEALTH
There is a reason why a good nights rest is related to “beauty sleep”, and specifically the outlook of our skin. A decrease in quality of our sleep causes an increase in cortisol levels, which is our main stress hormone, that has been shown to break down collagen, that is the main protein found within our body that makes up our skin, bones, muscles, ligaments and tendons. The quality of our skin is further worsened by the fact that when we lack sleep, we produce even less growth hormone which is responsible for cellular regeneration and growth, to keep our skin young.
IMPROVING YOUR SLEEP QUALITY
Avoiding exposure to bright lights before bed: Bright lights before bed suppress the release of melatonin, which as a result makes us tired much later in the night. Avoid the use of bright cool lights and looking at LED screens right before bed.
Limiting alcohol and avoiding caffeine before bed: If you do decide to consume either, drink them well before your bedtime during the day instead of later at night, as otherwise, they can disrupt your sleep or even cause you to not be able to fall asleep.
Doing something that relaxes you: This is crucial because, as in order to initiate sleep, we have to be in a calm state; a state that does not raise our core body temperature, pulse or blood pressure. Some ideas for calming evening activities include: Reading, taking a walk outside, taking a bath, drawing, meditating, journaling or relaxing with some music.
Exercising during the day: If we choose to intentionally do exercise during the day instead of before sleep, we are able to stay awake and alert during the day which allows us to focus and concentrate on our work, but will lead us to becoming more tired and in need of rest towards the evening, which is perfect for getting us ready for bed. Avoid activities that raise your pulse and body temperature right before bed such as vigorous exercise, and instead choose more calming exercises like as walking, yoga or stretching.
Eating a lighter dinner: We often have the tendency to overeat and especially towards the evening during the time of dinner. However eating too much too late can not only lead to overeating and eventually weight gain, but can also negatively impact our sleep as we may find it hard to fall asleep. Opt for finishing dinner no later than 8 pm to get a good nights rest. It has also been shown that the consumption of dairy before bed can make us fall asleep faster because dairy products contain both melatonin and tryptophan, where tryptophan is an amino acid that plays a large role in the production of the neurotransmitter serotonin that then aids in the further production of melatonin, the reason why we usually start to feel tired after a glass of milk.
Having a set morning and evening routine: This is a good tip because it creates regularity in our schedule and allows our body to get used to waking up and going to bed at the same time, so we start to naturally feel more tired towards the evening and more alert in the mornings, ready to start off a brand new day.
Avoiding having longer naps in the afternoon: Even though naps are generally recommended by sleep scientists and there has been a decent amount of research showing the many benefits of taking short naps during the day, however, it is important to consider when we nap. It is advised not to take a nap in the later afternoon as otherwise, that makes us unable to fall asleep during the night, so take your naps in the early afternoon or at noon for maximum sleep later on at night.
