The Importance of Sleep
Article by Stefan Burns - Updated November 2021. Join the Wild Free Organic email newsletter!
Sleep is a very important part of everyday life. The prevailing recommendation is that 8 hours of sleep everyday is ideal amount for health and wellness. Less or more than eight hours and negative health implications start to increase. The health effects of sleep deprivation is also well studied fact. Sleep is so important that sleep deprivation studies on rats and dogs have shown that extreme sleep deprivation can be fatal.
Health Impacts of Sleep
Here are some quick facts from the American Sleep Association (1):
50 - 70 million US adults have a sleep disorder.
37% of 20-39 year-olds report short sleep duration
40% of 40-59 year-olds report short sleep duration
35.3% adults report < 7 hours of sleep during a typical 24-hour period.
Sleep can take many forms. Most people sleep once a day in a single unbroken event lasting, sleep involves a 5 to 9 hours in length. Others follow a biphastic sleep schedule in which there are two periods of sleep everyday, typically one long and one short. Then there are extreme sleep schedules like those developed by the famous late Buckminster Fuller (which we do not recommend you try). However your sleep schedule is divided, a total of 8 hours of sleep per day is recommended. If you get less sleep than what your body and mind require for restoration every night, then there are some health complications you should be aware of.
In a study of over 100,000 volunteers, researchers observed that cognitive performance is impaired in people who deviate from the recommended 7–8 hours per night (2). A deviation from the 7-8 hours had little impact on short-term memory performance, but reasoning and verbal skills were heavily impaired. Those who self-reported sleeping less than 4 hours per night had lower scores compared to those who slept well, and had similar cognitive performance to people 8 years older then them. In persons sleeping less than 8 hours, reduced leptin and elevated ghrelin hormones were observed (3). This skewed leptin/ghrelin ratio has been found to be responsible for increasing appetite and hunger cravings. In fact, increased body mass index (BMI) was found to be proportional to decreased sleep. Sleeping for less than 7 hours per night conferred a 12% greater risk of death (4).
Without a proper 8 hours of sleep per night you’re more likely to be cognitively older, fatter, and one step closer to death than if you had slept a full eight hours per night. Poor sleep can be avoided through! This article will guide you through the science of why you might be having poor sleep and how to counteract this. At the end there is an action plan you can follow to improve your sleep right away.
The Sleep Cycle and Naps
Sleep can be broken down into sleep cycles 90 minutes in length. When you sleep for 8 hours, if everything is normal you will go through 5-6 sleep cycles. A sleep cycle can be further broken down into the stages of sleep: Wakefulness, Rapid Eye Movement (REM), Stage 1, Stage 2, and Stage 3.
By Schlafgut - Own work, CC BY-SA 3.0
Stage 3 is slow-wave deep sleep, and slow-wave-sleep is when the body heals and the brain consolidates memories (5). Stages 1 and 2 are short intermediate stages between stage 3 and REM sleep. Rapid eye movement (REM) sleep is when you experience dreams. Having adequate REM sleep every night has shown to be important for how alert, focused, and sharp you are the next day, and less REM sleep puts you at a higher risk of death (6).
While most of this article will focus on why you should get a good eight hours of sleep per night, daytime naps will also be discussed. When sleep deprived, naps can be a quick effective way to mitigate many of the effects of sleep deprivation. Longer naps have a more lasting effect than shorter naps, but the goal should be to resume a normal 8 hour sleep cycle as soon as possible. Keeping in tune with the circadian rhythm is important for many reasons, one of them being that brain waste clearance works better during sleep at night compared to daytime sleeping (7). The process of sleeping is important, but so is when you sleep. With that covered, here are the different types of naps you can take.
15 Minute Nap
If you’re feeling drowsy, fatigued, or have brain fog, a 15 minute nap can have you come feeling refreshed for 1-3 hours afterwards. The secret of the 15 minute nap is that very quickly you can descend into stage 2 sleep (see above). During stage 2 mental performance is increased, and in fifteen you’ll have gotten a mini tune-up, and the effects are immediate (8). A fifteen minute nap is too short to experience sleep inertia (that period of fatigue and drowsiness post sleep), so when you need a quick mental boost take a nap rather than reach for a cup of coffee. Naps used this way to help to improve your sleep and wellness overall.
The 15 minute nap is the best sleep option to utilize when you only have 15 minutes in the near future to catch some rest, and/or you require a cognitive boost right away.
30 Minute Nap
If you have longer than 15 minutes but less than the 90 minutes required for a full sleep cycle, then a 30 minute nap is a better option to improve mental clarity and also remove some physical fatigue. 30 minute naps enhance performance in reaction time and alertness compared to if you didn’t take a nap (9). A thirty minute nap extends your time in stage 2 sleep, improving the benefits compared to a shorter 15 minute nap. Sleep inertia will be slightly higher with a 30 minute nap that a 15 minute nap, but that should only last a few minutes at max.
If you sleep longer for thirty minutes you’ll enter into stage 3 sleep, and waking up from stage 3 sleep carries with it a lot of sleep inertia. It’s best to stick to a thirty minute nap or if you have the time go for a full 90 minute sleep cycle, and nothing in-between.
90 Minute Nap
The 90 minute nap is special because it encompasses one entire sleep cycle, from stage 1 and stage 2 sleep, through stage 3 slow-wave-sleep, and finally to REM sleep. If you need the biggest physical and mental boost midway through the day, a 90 minute nap is the way to go. 90 minute naps will boost performance for up to ten hours (10). The drawback of the 90 minute nap compared to the 15 and 30 minute options are that it creates more sleep inertia. Going through the sleep stages all the way to REM sleep takes one relatively close back to wakefulness though, and the sleep inertia from a 90 minute nap is slightly more than that from a 30 minute nap.
0 Minute Nap (Hypnagogic)
Hypnagogia is the experience of the transition from wakefulness to sleep. Ranging from a few seconds to a few minutes, this transition period takes people from conscious to unconscious experience, and unusual sleep phenomenon such as lucid dreaming, hallucinations, and sleep paralysis can sometimes be experienced during hypnagogia.
A hypnagogic nap is a nap that only lasts for seconds. To experience a hypnagogic nap without having learned to control the hypnagogia state, sit in a chair and hold an object such as a metal ball in your hand and try to fall asleep. Right before you’ll fall asleep, your hand will relax, dropping the ball, waking you up from the hypnagogia state. With practice, the balls will no longer be needed. Visionaries such as Albert Einstein, Benjamin Franklin, Nikola Tesla, Ludwig van Beethoven, Salvador Dalí, Isaac Newton, Thomas Edison, Aristotle, and more all have credited hypnagogic naps with boosting their creativity and insight. I personally can attest to this phenomenon. All of my best ideas and revelations come to me as I straddle wakefulness and rest, and I’ve found that if I transition back to wakefulness instead of sleep after experiencing hypnagogia, I feel rested with my mind firing at max creative capacity.
Factors that Influence Sleep
There are a many factors that influence sleep, and they range from minor to major in effect. It is important to be aware of these different factors, which range from light exposure to diet, and how they affect the circadian rhythm. The circadian rhythm is a natural, internal process that regulates the sleep-wake cycle. When making changes to improve sleep quality and/or quantity focus on the most encompassing changes that positively effect the circadian rhythm. The methods that are the most effective in improving sleep often require the biggest lifestyle changes, so expect these changes to take time. Patience will be required if you wish to make lasting change and create a lifestyle which supports quality sleep and overall health and wellness.
Below is a list of the most important factors that can influence sleep. At the end of the article is a quick-start guide that will condense this information into actionable steps.
Chemicals: It’s well known that chemicals like caffeine affect sleep, but other chemicals, some of which are naturally produced, can also impact sleep.
Exogenous Sleep Disruptors
Nicotine - the additive chemical found in tobacco, is a stimulant and disrupts sleep by increasing sleep latency (how long it takes to fall asleep), reduces quality, fragments sleep, and reduces overall time slept.
Alcohol - a depressant, the more drinks that are consumed before bed, the greater the impact on sleep quality. You might fall asleep faster, but REM sleep (which is mentally restorative) is notably reduced after a few hours.
THC/CBD - cannabinoids produced from cannabis, THC is a psychoactive chemical while CBD is non-psychoactive. Both promote feelings of relaxation but THC triggers dopamine release.
Exogenous Continued
Caffeine - a stimulant found in coffee beans and green tea leaves, caffeine promotes wakefulness and releases adrenaline. The half-life of caffeine is ~6 hours, so if you have 100 mg caffeine upon first waking, 18 hours later when it is time to sleep you will still have 12.5 mg of caffeine in your system.
Theobromine - a stimulant found in cacao, theobromine is very similar to caffeine in its effects.
Phthalates - chemicals commonly found in plastic products, phthalates are endocrine disruptors and by affecting hormones can disrupt sleep through phenomenon such as hot flashes. Bedding materials commonly degas phthalates.
Endogenous Sleep Influencers
Dopamine - a naturally produced feel-good neurotransmitter, increases in response to things that bring pleasure, and higher levels of dopamine disrupt sleep.
Cortisol - a steroid hormone, cortisol peaks in the morning when you wakeup. Cortisol is released by the adrenal glands when stressed, though the overall cortisol release schedule is dependent on your circadian rhythm.
Melatonin - a hormone primarily released by the pineal gland, melatonin helps regulates the sleep–wake cycle.
Consistency: More consistent day-night schedules improve sleep quality. The circadian rhythm is based on the light and temperature cycles of the sun, and the further you stray from these natural variations, the more disrupted your circadian rhythm becomes. All the factors in this list affect your circadian rhythm, and therefore your sleep, but what also effects your sleep is how consistent you keep these factors everyday. Changing any factor, whether for the positive or negative creates circadian rhythm volatility, so move the needle slowly, introducing one optimization at a time, and make it a lasting habit.
Sometimes it’s not possible to be fully consistent, such as with jet lack from travel or life events, and in this case do your best to stay calm and reduce the volatility to your circadian as much as you can using the different takeaways that you glean from this list.
Electromagnetic Radiation: The Earth is buzzing with electromagnetic energy, both naturally occurring and now man-made. Little is known on how magnetic fields influence our physiology. Our bioelectrical system is just as developed as any other system in the body like the circulatory system, it’s just not well understood. There is evidence that the frequency and amplitude of electromagnetic fields can impact sleep (11), and if you’re experiencing poor sleep you might consider turning the WiFi routers in your home off ever night and keeping note of your sleep patterns.
I personally have done this and I notice I sleep better with the WiFI router off.
Environment: Environment is a multi-faceted word that means many things. Environment means more obvious factors like temperature and background noise, but environment can also mean more nebulous factors. Maybe you live with other individuals with volatile schedules who are highly stressed and emotional. Perhaps a family pet needs to be let out every night to do their business, or there is temporary construction nearby that starts at 6 am. There are endless ways your environment effects your sleep schedule and quality of sleep, and you can influence these factors to various degrees.
“God, grant me the serenity to accept the things I cannot change, courage to change the things I can, and wisdom to know the difference.”
This quote is very true as it relates to your sleep environment. Make the changes and optimizations you can in order to sleep better, but remain calm with what you can’t change. Getting stressed or worried about what you can’t change will only make you sleep worse.
Food: Food has a big impact on your sleep. The timing and composition of meals determines your blood sugar levels, which in turn impacts your energy level and brain activity. Depending on what you eat right before bed can have an impact on how well you sleep that night meal right before bed. Fiber increased slow wave sleep and reduced stage 1 sleep (light sleep) whereas sugar and saturated fat increased stage 1 sleep and arousals (12).
When meal timing is kept consistent, the body adapts and the circadian rhythm normalizes, even if the meals are very early or very late. When the timing of meals change, the circadian rhythm shifts and sleep is disrupted (13)
Alcohol is a well known sleep disruptor. As a depressant, a few servings of liquor might help you fall asleep faster, but overall sleep quality will be worse, with REM stages suffering the most (14).
Light: Our existence is light, so it is no surprise to find out that light has a huge impact on sleep. Light is the main input the circadian rhythm bases its calculations off of, and the intensity, wavelength (color), and timing of light all change the response of the circadian rhythm (15). The transition of dim to bright light in the morning induces an immediate rise in cortisol (16), the stress hormone, promoting wakefulness. During the day, blue and green light dominate the sky, promoting alertness through changes in brain activity (17). At night blue light suppresses melatonin production, the sleep hormone, in a dose dependent manner (18). Any light after dark disrupts melatonin production and has an influence on sleep onset and quality (19), it’s just lower wavelength light has the least impact.
Being mindful of all light, and it’s effects on your sleep, is one of the biggest things you can do to positively impact your sleep quality and quantity.
Medications: There is a chance with any drug or medication for one of the side-effects to be sleep disruption. Alpha and beta blockers, SSRI antidepressants, statins, corticosteroids, ACE inhibitors, and diuretics are just some of the drugs which can cause insomnia, daytime drowsiness, decreased REM sleep, nightmares, the list goes on.
Getting good sleep every night is foundational to good health, and every effort should be made to get off medications which impact sleep. Every holistic effort should be taken to return to a healthy lifestyle not requiring any drugs or medications, but that desire has to manifest internally as a deep seated desire.
Pain: It’s no surprise that pain can disrupt sleep, it is something everyone has experienced. Chronic pain can cause regular sleep disruptions, whereas acute pain might only temporarily disrupt sleep. The issue with pain is that it can disrupt sleep, and then the lack of sleep can cause worsening health outcomes, which serve to further increase the pain. It’s a troubling cycle, and to break it pain and anti-inflammatory supplements can be of use. Curcumin, sulforaphane, and CBD are all effective natural anti-inflammatories which can reduce chronic and acute pain depending on their application.
Sex: We know that poor sleep negatively impacts your time in-between the sheets, but how does sex impact sleep? How sex can impact sleep is very individual. During sex, dopamine and oxytocin are released, which can create pleasant feelings which reduce stress, and after sex other hormones like prolactin can cause feelings of relief, relaxation, and sleepiness. These naturally produced chemicals can improve sleep, but for some sex might be too energizing. Likewise, if you’re disrupting your regular sleep schedule by staying up late and being frisky, this will only impact your sleep negatively.
Stress/Anxiety/Depression: Stress and anxiety can deeply disturb your sleep (20), and overtime this can lead to chronic sleep issues. How stress and anxiety affect sleep is similar to the pain-sleep downward cycle. Stress can disturb sleep which can worsen stress and so on. Overtime, or due to other factors, depression can become an issue, which can range from mild to life threatening.
Depression and sleep are closely linked. Decreased REM sleep can exacerbate depression, and depression can lead to insomnia.
Temperature: The temperature of the environment and your body temperature have a big impact on sleep. Finding the right balance between hot and cold is important for sleep quality. When sleep environments are too warm, slow wave and REM sleep are decreased, while wakefulness increases (21). In cold environments, shivering will negatively affect your sleep, but when bundled up the issue is mitigated. The best solution is to sleep in a cool to cold environment and then add warmth to your desired level with bedding materials.
Heat therapy which has many benefits, raises internal body temperatures and can impact sleep. Heat therapy at night (via a bath) while on the decline of the circadian rhythm was found to improve sleep onset, increase the deepest stage of slow-wave-sleep, but decrease REM sleep (22). Typically you don’t want to decrease REM sleep. The same heat therapy done during the incline of the circadian rhythm (think late afternoon) didn’t have any effect on sleep.
Keep Sleep Simple
As you can tell, a lot of the health factors which disrupt sleep end up feeding their own condition, making it worse and creating a downward spiral. When or before this happens, it is important to intervene with wellness therapies which are proven effective in helping improve sleep, reduce stress, reduce pain, and increase happiness. Unless positive change is inserted into the equation, healing will not occur. Wellness activities as simple deep abdominal breathing or time spent in nature being in awe can change the conversation, getting wellness and sleep back on track.
Countering bad sleep habits with wellness activities is especially important as you can tell there is significant overlap in the categories above. When on a quest to improve sleep quality, it is best not to pick and choose which habits you’ll change and which you won’t. A holistic lifestyle approach is needed, and once normal sleep patterns have resumed, then you can patiently experiment with what minor changes you’d like to try to accommodate.
Native Americans used dream catchers as spiritual tools to give good dreams to those who slept below them. Bad dreams are caught in the webbing and burned in the light of the morning sun.
First, lets lay out desired sleep goals:
Sleep schedule in-sync with natural circadian rhythm
8 hours sleep per night
Fast sleep onset
Reduced disruptions from elevated alertness and wakefulness.
Quality slow-wave-sleep
Regular REM sleep
Upon waking you feel alert and refreshed.
To accomplish the above sleep goals, lifestyle modifications will need to be made. These modifications are done with the best intentions and creating wellness habits out of these tips will positively impact your life given consistency and time. Some of these modifications might go against your established behaviors, so before you start the below program make sure you are 100% committed to improving your sleep. Only if you have a strong innate desire to improve your sleep and be healthier will these changes stick.
Holistic Sleep Improvment Protocol
Establish a hard bedtime 8.5 hours before when you would like to wake up every morning. If you need to be up by 4 am that means bedtime is 7:30 pm. 6 am wake-up means 9:30 pm your head is on the pillow. The extra half hour is a cushion that accounts for the time it takes to fall asleep. You need to be consistent with this. Even if you’re not tired initially, create the habit and go lay in bed. Do you best to make your wake-up in the morning coincide with the rising of the sun.
Make the bedroom a place for sleep maybe sex and nothing else. If you have a TV in the bedroom, move it elsewhere. If you charge your phone or tablet on your bed stand, move the chargers to a different room. Actions dictate how we respond in different environments, and if you want the bedroom to be a place where you sleep, then it needs to be a place of sleep and nothing more. Watching TV or being on your phone gives your mind the expectation of alertness and activity in an environment where that strictly shouldn’t be allowed. Removing electronics and bright lights from the bedroom also reduces light exposure and melatonin production will be unaffected.
Keep the sleeping environment cool and exposed to the outside temperature, even in some small way. The circadian rhythm is driven by the light and temperature cycles of the Earth and Sun, and the further you remove yourself from the natural world the more your sleep will suffer. This goes for your electromagnetic connection to the Earth too, and being grounded at night can further improve sleep and reduce inflammation.
Be conscious of light throughout the day, and when the sun starts to set, all electronics should be put away and not used. The use of electronics 2-3 hours before sleep is strongly not recommended. Bright lights in the house should be dimmed, replaced with hue light bulbs (and set to a low kelvin temperature) or candles can be used. Dim lighting at night is better for your circadian rhythm and melatonin production while also being a more passionate creative environment. I have hue color changing lights and highly recommend them for reducing light exposure at night and also to schedule them to slowly turn on with the sun. They’re a game changer. At night put on some blue blocking glasses to further reduce the effect of having lights on. It might seem like overkill, but at night its very dark outside, and even dim lights affect the circadian rhythm. I use Felix Gray blue blocking glasses and notice if I use them consistently at night I sleep better.
Cut the caffeine and other stimulants. Caffeine has a long half-life and drinking a cup every morning builds up a chronic dependence on caffeine to be alert and wakeful. Having any caffeine in the afternoon or evening is a strict no. The occasional cup of coffee or tea isn’t a problem, but don’t make it a habit. Likewise, nicotine and alcohol are obvious sleep disruptors, and for health reasons overall shouldn’t be used at any time other than extremely sparingly. Skip the claw, la croix is a better alternative, and if you are addicted to nicotine, try transitioning off cigarettes to cannabis dry vaporization, a healthier alternative which is easy to stop. The cannabinoids might help you sleep too.
Exercise in the morning or afternoon, but not evening. Besides a peaceful walk at night, exercising at night stokes the energy systems of the body to ramp up, releases cortisol, and will delay sleep onset. Exercise and movement is foundational to a healthy life, but not at the expense of good sleep. The best way to make sure you exercise in the morning is to establish a consistent morning routine. Start your morning with a movement flow, yoga, calisthenics, a run or walk, there are so many options, and if you do this you’ll feel great throughout the rest of the day.
Start a journal and keep track of your sleep. Recording when you go to sleep, wake up, and sleep quality is a good way to pair your diet, daily actions, and habits to your quality of sleep. If your mind is still spinning before going to bed, committing these thoughts to paper can quiet the storm helping you fall asleep faster.
Meditate every day for at least 15 minutes. Meditation is the best way to practice calming your mind, it increases mindfulness, and provides an opportunity to raise your level of consciousness. The act of physically doing nothing might seem counterproductive, but through meditation you can unlock many internal and external secrets and truths that would have remained hidden to understanding. Meditation will impact your life in wide-ranging ways, and it will improve your sleep a lot.
Spend time in nature every day, increasing your consciousness of the world around you while also enjoying the mind clearing and emotionally calming benefits. You can practice your meditation during this time, focus on deep abdominal breathing, and feel the stress melt away.
Eat a healthy diet rich in fruits and vegetables and don’t eat too close to bed time. Additionally, keep your meal timing consistent so as to not disturb your circadian rhythm. For your last meal, at most 2 hours before bed, have a salad or high fiber vegetable like squash. Change your dietary mindset to not seek out foods you crave but instead the nutrition your body needs. Avoid all sugar before bed.
To aid the sleeping process, there are some supplements which are known to help. 200-400 mg of magnesium glycinate an hour or two before bed will help improve sleep quality (23, 24), or simply eat 1/4 cup of nutrient-dense pumpkin seeds. 10-20 grams of glycine-rich collagen, or a meal composed of pulses (beans, lentils, chickpeas) which also contain a lot of glycine, before bed will improve sleep onset and quality (25).
Drink plenty of water throughout the day. The human body is made up of 70% water, and being in a state of chronic dehydration has serious long term health consequences. Upon waking, drink 24-32 oz pure filtered water and do the same before bedtime. Being dehydrated means your mouth and nasal passages will be more dry, increasing your chance of snoring and waking up with dry mouth. Dehydration will also increase your chances of getting leg cramps at night, an unpleasant and wakeful experience. Drink water everyday to stay healthy, skip the other liquids and aim for a gallon of water daily.
Sleeping is an Advantage, Use It
It is clear that sleep is a critically important component towards achieving optimal human health, for achieving mental clarity, and for healing your body.
Modern culture doesn’t emphasize wellness, and has yet to fully realize the importance of a well rested 8 hours of sleep. Be cutting edge by going low-tech with your sleeping habits. You’ll experience a calmer mind, less turbulent emotional states, feel stronger and be better rested, and you’ll be less likely to die. Without good sleep you will not age gracefully and experience the quality of life you want.
Updated September 2020
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