Chat surrounding sleep and how to get a good night’s rest has become popular amongst conversations. Probably not only due to peoples increased interest in following their sleep-wake cycles on sleep tracking apps but also due to our increased awareness of how quality sleep can improve overall quality of life.
One hormone that plays a serious role in stimulating sleep is melatonin. Melatonin is a part of our circadian rhythm, our internal 24hr body clock that works with the hours of natural light and darkness. Essentially, it is our bodies way of staying awake during the day and being able to sleep restfully at night.
So how do our circadian rhythms work? When the sun rises our bodies release the hormone cortisol from our adrenal glands which increases alertness – our get-up-and-go hormone. When we then venture out into the sunshine and natural day-light the sun exposure activates melanin in the skin and communicates to our pineal gland (in the brain) to make melatonin. Throughout the day this gradually reduces our alertness and is secreted the most at night to induce the feeling of sleepiness.
It should be noted that adequate and appropriate secretion of melatonin is crucial for inducing our sleep not exactly for staying asleep. However, there are factors that can disrupt melatonin production leaving you tossing and turning, proving it difficult to get to sleep.
Let’s take a deep dive into what could be disrupting your body clock and ways you can avoid disruption for a good night’s sleep.
Factors Affecting Melatonin
Having poor sleep or a disrupted circadian rhythm, whether that is due to suboptimal melatonin secretion or not, is the driver of many health issues like obesity and cardiovascular diseases. Not to mention impacting our everyday fatigue, irritability and focus.
The supplementation of melatonin is one way of combatting poor sleep such in the case of sleep disorders like non-24hr sleep wake disorder and jetlag. Though, there are certain factors that should be modified first before following supplementation, which could be wreaking havoc on your natural melatonin production. So, why can’t you get to sleep?
Diet: Melatonin is produced from the essential amino acid tryptophan. So, it’s no wonder that if our diets are lacking in foods rich in tryptophan then this can affect sleep. Reports from studies conducting improvements in sleep onset have found that tryptophan doses as little as 1g can ameliorate sleep onset disorders.
Another common factor could be that you’re consuming a little too much caffeine, especially if that happens to be in the evening. We’ve all been there, deadlines, exam prep, long waits at the airport. Caffeine, and mostly in the form of coffee, is one of the most globally utilized stimulating substances which can disrupt sleep. Although it may not have the same effect on everyone, reaching for another coffee may not be the best idea to keep your energy flowing. Studies have found that even a few days abstaining from the humble brew can help induce sleep onset in some individuals.
Exercise: We’re sure you’re all familiar with the feeling of getting into bed after a day that you’ve partaken in some tiring physical exercise, it feels rewarding! However, what about exercising too close to bedtime? Studies have shown that if partaking in vigorous exercise within 1 hour of going to sleep – think going for a run, late-night exercise class times or riding home from work – this can affect sleep onset. This is due to the effects post-exercise has on raised body temperatures and heart rates, and also increased circulating adrenaline levels.
Light: The most impacting factor in melatonin production is light. After all, it does follow the natural movements of the sun. Our new world of computer screens, phone screens and artificial lights is unfortunately having a large impact on our daily melatonin production. This is of course largely due to blue light sources that are impacting our melatonin.
Research suggests that exposure to bedroom lights (not dimmed or yellow lighting) before going to sleep will suppress melatonin causing later onsets of sleepiness, changing our body’s perception of the time of day. Aka we still think its time to hustle as its not dark yet. This, of course, is further heightened by our obsessive scrolling and screen time.
Managing Melatonin
The great news is that the above factors are modifiable, although a few may be harder to shake than others.
Diet: Eating foods rich in tryptophan is one way of boosting your melatonin. Foods high in tryptophan include turkey, whole milk, tuna, cheese and oatmeal. Though conveniently some foods are actually high in melatonin. Include foods like eggs, fish, grapes, cherries, strawberries, mushrooms and tomatoes as melatonin is found in these sources in the highest amounts.
Also, our favourite way of boosting energy levels come 3pm - instead of reaching for another coffee - is our Active Cycle Hot Chocolate. Although it is specially formulated to support women’s menstrual cycles, it may be just the afternoon or post dinner pick me up you need. Plus its super nourishing for your body so win, win!
Exercise: Booked a late-night exercise class? If you’re finding that you have trouble falling asleep after class it may be time to switch it up for a morning workout or try a lower intensity class like yoga. Lower intensity forms of exercise are less likely to produce the stimulating adrenaline levels that a run or HIIT class would.
Light: This is your sign to ditch the late night or just before bed scrolling. Set-up a stricter bed-time routine just like you would with a morning routine. If you tend to go to bed at 10pm give yourself a curfew of at least 30 minutes to an hour before bed of no screen time. Read a chapter of your book, do some before bed stretches or write down all the things you need to do tomorrow to get them off your mind before going to sleep. Investing in some blue-light blocking glasses may also be beneficial if you spend a lot of time in front of screens for work to help induce melatonin production.
In some instances melatonin supplementation may be needed. However, please speak with a health professional about your circumstance to get personalised advice that is right for you before supplementing.
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