What is a Natural Sleep Cycle (or, Sleep-Wake Cycle)?
Healthy, natural and deep sleep results mostly from our internal 24-hour body-clock, known as the 'circadian rhythm'.(1)
Crudely speaking, in normal circumstances this is responsible for around 8 hours of sleep and 16 hours of wakefulness every day.(2)
At various times throughout the day, chemical messengers in the body - largely derived from the foods we eat - signal the body towards states of alertness or drowsiness.(3)
It is this system, which is also used to stimulate the body in times of panic, which brings about chemical changes towards bed time that lead to reduced body temperatures (4), heart rate and alertness in preparation for rest.
A controlled spike in inflammation is also noticeable before we fall asleep which is thought to prepare the body for repair and recovery while asleep.
Stimulants including caffeine, exposure to blue light (5), the foods we eat, our age, and the health of our neurological system can all affect sleep quality and depth.
In brief, a healthy sleep can be defined as 7-9 hours of, at least relatively, undisturbed rest every night.
During a healthy night, you will go through different phases and depths of sleep, including REM sleep (rapid eye movement), in a cycle.
As well as depth and duration (6), consistency is key. Homeostasis - the practice of the body maintaining its healthy balance - strives for consistency.
How to Deal with Insomnia (sleepless nights) Naturally
So which pathways exist for us to naturally influence our sleep?
The first step of improving sleep quality has to be a review into your current sleep quality - so as to uncover any obvious issues preventing normal circadian functioning.
For example, the simple question of 'what do you do just before you go to bed' could reveal in itself an excess of blue light from smart devices if someone is to answer with 'watching TV and using my mobile phone'.
Many people find creating an evening routine helps them achieve consistent sleep.
For example, a meditation or breathing exercise, turning off your smart devices a few hours in advance and only getting into bed when your intention is to actually sleep can all make a difference.
The mind utilises association. If it associates a space with activity or work, it will not expect to be falling asleep in that same place. So avoid using your bedroom as an office - something students are too often guilty of.
In addition, using your phone in your bed every night creates an association with that activity and again, not sleep.
Natural methods for improving sleep quality:
- Plant-derived constituents including tryptophan, valerian, or passionflower*
- Meditation and mindfulness for sleep
- Nutritional considerations, including potential deficiencies/excess (e.g. too much sugar or caffeine)
- Removal of blue light stimulation in the hours before bed (mobile phones, bright TV screens and LED lights to be turned off)
- Consistency with night-time routines
- Breathing exercises
- Improvements in microbial health of the gut microbiome
Natural Sleep vs Medicated Sleep
Medicated sleep can come with unwanted side effects.
Medicated sleep cannot guarantee a true, deep sleep with various phases including REM.
When sleep can be achieved naturally, we do not have to rely on medications for something innate to us.*
Natural sleep is therefore most justifiably the best, or ideal, solution for the majority of people given that their condition allows for it as it is most likely to be in tune with what your body requires, at the correct depth, for the correct time.
Foods and Plants Associated with Better Sleep
Let's take a look now at the relationship nutrition, herbalism, and sleep quality have and the various food choices we can make that influence our rest.
'Nutrition' is believed to have a 'significant impact on sleeping wellness'(7).
From vitamin D deficiency (7) preventing normal sleep, to an excess of high GI (glycemic index) carbohydrates (8) keeping us awake - which, broadly, are those with faster releasing sugars - the foods we eat and how our body use them largely influence sleep depth and quality.
In terms of vitamin D, it is advisable to spend plenty of time exposed to sunlight to avoid sleep disorders, but as for carbohydrates, the best case may be to simply avoid eating sugary foods, or those with faster-releasing sugars, in the hours close to bed-time.
In addition, 'higher saturated fat intake' (7) was associated with an increased chance of markers for poor sleep quality.
Specific proteins can also have specific effects on how we fall asleep and stay there for a full night.
Amino acid tyrosine leads to the production of norepinephrine (NE) which may not be beneficial to us in the middle of the night but works wonders in lifting our alertness during the day.
Another protein, tryptophan, is found in tofu and pumpkin seeds (12) and has become associated with good sleep health due to how our body, thanks to our gut bacteria, can utilise this amino acid.
The benefits of tryptophan come as a result of it being a precursor to serotonin, and serotonin being a precursor to melatonin makes tryptophan a protein with the potential to result in increased numbers of two chemicals vital for sleep.
'Melatonin is a hormone secreted at night by the pineal gland in the center of our brain to help regulate our circadian rhythm.' (13)
Food sources (tryptophan):
- Squash/Pumpkin Seeds
Next up is Kiwifruit.
Kiwifruit has been associated with better sleep 'onset, duration, and efficiency in adults with self-reported sleep disturbances' (9).
Kiwifruit is rich in serotonin, a hormone that functions as a neurotransmitter, which plays a major role in the initiation of sleep and sustaining it throughout the night.
Another study found similar results for a specific tart cherry juice. (see source 10)
Cannabidiol (CBD) is an immuno- and homeostatic regulator that has also been studied for its effectiveness against insomnia.
Cannabidiol binds with receptors in the body and as a result brings various health-promoting changes without psychoactive effects.
'Research into cannabis and insomnia suggests that cannabidiol (CBD) may have therapeutic potential for the treatment of insomnia.' (11)
CBD products, particularly in the UK, are becoming more and more commonplace due to the potential therapeutic benefits the cannabinoid presents us with and their intrinsic connection with the human body.
Valerian Root, or valerian, is another commonly prescribed naturally-occurring herbal remedy for insomnia.
A meta-analysis found valerian to be a 'safe and effective herb to promote sleep and prevent associated disorders' (14).
In addition, this may be beneficial for anxiety sufferers.
That said, evidence for the use of valerian as effective is relatively limited, and more research may be necessary.
Passionflower (passiflora)* is yet another sedating, naturally occurring herb.
Passionflower is commonly used in over-the-counter sleeping tablets.
'Sleep quality showed a significantly better rating for passionflower compared with placebo' (15).
Lavender is associated with better sleep quality and can be consumed in many ways (17).
A controlled trial found inhaling lavender did make measurable differences to sleep quality.
The use of lavender is well-documented as a natural relaxant associated with improved sleep.
GABA, or gamma-aminobutyric acid, is a neurotransmitter (chemical messenger) that is associated with bringing about sensations of calm and relaxation.
'It is well established that activation of GABA(A) receptors favors sleep' (16).
Food sources (GABA):
- Brown Rice
- Sweet potatoes
Meditation and Mindfulness
Several studies suggest mindfulness meditation can benefit general wellness, including sleep quality.
This is a highly effective psychotherapeutic which gets more beneficial with practice.
The sleep-inducing effects of meditation can for some people set in right after the first session, for others regular practice is needed.
'Mindfulness meditation helps fight insomnia, improves sleep', according to the Harvard Health Blog. (19)