Girl wearing grey t-shirt sleeping face down on bed

The Ultimate Guide to Melatonin and Its Impact on Quality Sleep

Most of us love our sleep. All of us know the importance of sleep. And yet many of us struggle to get good quality sleep.

If you’ve ever scratched the surface and done even a teeny bit of research into sleep, you’ll likely have come across references to melatonin. If you’re getting serious about sleep, you likely have some further questions.

How does melatonin work in the body? What role does it play in brain health and healthy ageing? What are the key differences between synthetic and non-synthetic melatonin? How does a physiological dose of melatonin work?

Let’s dig in.

Want to listen to this instead? Press play to hear the full conversation between Dane Renshaw BNat (Hons) and Cathy Avila PhD from Atomic Regs as they discuss the impacts of melatonin in the body, different forms of supplementation and some surprising, lesser-known research findings.

What is melatonin and how does it work in the body?

Melatonin is a neurohormone that’s naturally produced by the body, especially at night-time in response to darkness. As the night draws in and it gets darker, our bodies respond by producing a spike of melatonin. It’s one of the key aspects of initiating sleep. Of falling asleep. Of having a desire to go to sleep.

You know that lovely drowsiness you feel naturally in the evening?

That’s melatonin kicking in.

This is known as the melatonin spike. Our bodies tune into the light level. Our eyes respond by picking up the level of light and send a signal up into the brain to produce melatonin.

In the morning as it lights up again, melatonin is suppressed.

It’s a 24-hour cycle, commonly referred to as this circadian cycle.

The circadian cycle

It can be helpful to think of the circadian cycle in terms of a day shift and a night shift. When melatonin floods through your system – which is typically when it’s dark – it can affect every cell of the body. All of our asleep functions happen in the presence of melatonin.

Melatonin is essentially doing a whole load of background work and preparation during the dark hours. It’s a bit like the cleaners at a station who ­after the crowds have gone home get everything ready for the next day’s rush hour.

Research shows us that melatonin has this incredible function in terms of restoring brain energy and helping us to consolidate memories from the day before. It even helps clean out the brain’s metabolites through the glymphatic system. And it gets the nervous system functioning for its night role.

As morning comes and the light comes up, melatonin is supressed, which effectively heralds in the day shift. That’s when you feel alert and refreshed. All of the daytime functions that the body needs to achieve take place when melatonin is at lower levels.

So we know that there is a 24-hour cycle. We know that melatonin rises in response to darkness, which helps to initiate sleep. We also understand that there are three key aspects to sleep – falling asleep, staying asleep and waking refreshed – and that melatonin plays a big role in all three of these.

And importantly, we know that a lack of quality sleep can impact a whole suite of different things downstream, such as your physical health, mental health, cognitive function and restoration of body and mind.

Did you know melatonin is an antioxidant?

We know melatonin is important for sleep. But did you know it’s also really important for other areas of wellbeing, including healthy aging and cardiovascular health?

Something to bear in mind is that melatonin is a really powerful antioxidant. We know that antioxidants have a role in maintaining cardiovascular health and also gut health, among other things.

Reducing free radical formation is something that will help us to age well. While we don’t generally think of that aspect of melatonin, the antioxidant activity of melatonin is right up there with some of the best.

Technology, blue light and the melatonin spike

Isn’t it wonderful how so many of us have access to good quality technology? We can quickly text friends, jump online, search for things, entertain ourselves.

Unfortunately, it’s often only once work is done for the day and when the kids are in bed and dinner is tidied up that we might sit down to our devices for social or browsing time. And then when do you actually put your device back down? Just before bed? While you’re in bed?

Whether it’s your phone, laptop, iPad, tablet, it’s all the same.

The vast majority of us do it. Surely it can’t be that bad?

It’s certainly not great. Here’s why: our devices emit blue light. Blue light is a high energy wavelength of light that suppresses melatonin. This means that if you’re looking at your device late in the evening and just before bed, you’re actually going to reduce the strength of that melatonin surge. Over time that is seriously going to erode the quality of your sleep.

When we inhibit that melatonin spike, we’re less likely to fall asleep, we’re less likely to stay asleep, and we’re less likely to wake up feeling refreshed.

Re-read that last paragraph. It’s that important.

The importance of the melatonin spike

Without a melatonin spike, all our background, restorative processes are compromised. The ones we know most about relate to brain function, but it’s of course much broader than that.

All our physiological systems need that downtime. These include memory consolidation, the clearing of the glymphatic system, the restorative processes that allow us to reset and be ready for a new day.

It really is quite a complex process.

Interestingly, the glymphatic system seems to work during the slow wave sleep cycle and melatonin – particularly at the physiological dose (see below) – doesn’t seem to impact that slow wave. Without slow wave cycles during sleep, the metabolites and waste products that accumulate during the day can’t be effectively removed during the night, and this build-up of toxins in the brain leads to a whole range of cognitive issues and chronic illness.

This is particularly interesting when you consider the oft told accounts of older people who claim they need less sleep.

There’s actually something else going on here that’s important to note.

Melatonin levels decrease as you age

You know how people often say that as you get older you don’t need as much sleep? We’re going to go against the grain and say that this is almost certainly a myth.

Let us explain.

One of the things we also associate with ageing is people searching around in their memory for names and being more forgetful than they may have been in the past.

Those two things – having a good night’s sleep and memory – are completely connected. And then when you dig a little deeper, you discover that melatonin is in the background.

As you age, your melatonin levels decline.

Melatonin levels naturally decline with age. Rather than people needing less sleep as they age, really they’re sleeping less because of declining melatonin levels.

Some questions to consider:

  • Is less sleep actually healthy?
  • Is this really the best and healthiest way to age?

Likely it’s no and no to the above, particularly where a reduction in melatonin production leads to problems with memory and other cognitive decline and they’re problems we’re hoping to avoid (or at very least postpone for as long as possible).

Ageing and blue light aren’t the only things that influence natural melatonin production. Unfortunately, it appears that certain medications can also have a negative impact.

How certain medications can impact natural melatonin production

Did you know that many common medications, especially those that are typically taken in the long term, have a side effect of interrupted sleep or lack of sleep quality?

Things like beta blockers and even non-steroidal anti-inflammatories.

While you might need them and they may be incredibly important to your overall health, they’re also impacting another massively important aspect of long-term health: taking such medications is linked to a decrease in melatonin levels.

A lot of people take – and need – these medications. Beta blockers, for example, are one of the most prescribed pharmaceuticals and many people tend to just accept the side effects that come parcelled up with their benefits. Such as not getting a good night’s sleep.

But what if more people understood that taking certain prescribed medications can impact melatonin levels, which in turn impacts sleep quality?

With better awareness and understanding we become empowered to modify our life and better support melatonin regulation throughout the body, whether that be through reducing blue light, supplementing melatonin or improving diet to facilitate overall health and wellbeing.

What you need to know about melatonin supplementation

We know that in its most natural form, melatonin is a neurohormone in our body. But what about when we take a melatonin supplement?

In short, melatonin in melatonin supplements is typically derived from one of two sources:

  1. Synthetic chemicals.
  2. Animal sources.

Melatonin in the body is produced in the pineal gland. This is true for both humans and animals. As a result, melatonin is sourced from the pineal gland of certain animals, typically cows, pigs and even sheep.

Not keen on that option? Understandably there are some concerns around this form of melatonin but the only other option that’s commonly discussed and promoted is synthetic melatonin.

However, if you do a search to try to discover what exactly synthetic melatonin is made of, you’re likely to hit a bit of a wall.

The main information that comes up from a search is around how much ‘safer’ it is to take in synthetic form. But where’s the info on what it actually is? Why can’t we get more information on the synthetic chemicals that make up synthetic melatonin?

What if we told you that a common source of synthetic melatonin is petrochemicals? That’s right. So now there’s a choice between petroleum based or melatonin taken from the pineal glands of animals?

If neither of those options feels like a good fit, here’s some good news:

Plants also produce melatonin!

For emphasis, we can add that to the original list of sources so it’s more complete:

  1. Synthetic chemicals.
  2. Animal sources.
  3. Plant-based sources (AKA phyto-melatonin).

Plants, it turns out, produce the identical melatonin molecule as found in our brain. Yes, they may use it for completely different things, but the key point is that it’s the identical molecule to the melatonin produced in your brain.

So now it’s possible to get high quality, sustainably sourced, traceable and standardised melatonin that’s derived from plants and has the exact same effect as other melatonin products because it has the exact same bioidentical chemical structure to melatonin produced in the brain.

For those of us in the nutraceutical space, this is exciting stuff.

The difference between high dose and physiological dose

Something equally exciting is the research that’s gone into melatonin dosing.

Different people naturally produce different levels of melatonin, and this typically sits between 0.3mg to 0.9mg. As discussed previously, certain factors, such as age, impact these natural levels.

The average person taking a prescribed melatonin supplement will typically be directed to dose somewhere in the region of 3mg.

One of the more interesting theories that recent literature findings show is that it can be highly effective to dose within the same range as our natural melatonin levels. In effect, you’re more or less supplementing your own individual production of melatonin. You’re keeping it within that low dose between 0.3mg to 0.9mg.

The research suggests that just staying within that range – just adding it to what you’re normally producing – will often produce really good and long-term effects. An additional upside of taking a physiological dose is that it also improves the chances of waking up feeling refreshed.  

So taking a physiological dose is seemingly a great option, particularly in longer term use.

And when would you bring in the big guns? Say you’ve been on an international flight and you’re jet lagged. Your circadian rhythm is out of whack, your 24-hour clock is completely off. Or maybe you’re thrown off from a nightshift or two and want to get back on track.

That is the time to go for the higher dose. Reset your biochemistry.

But a word of warning: higher doses appear to be most effective in the short term (e.g. seven days). Once you’re through the thick of it, consider switching to a physiological dose or stopping altogether so your body has a chance to produce its own balance.

What surprised you about this? Will you do anything different now you’re across the many roles melatonin plays, how it’s affected, the different forms it comes in and the fact that there’s an increasing argument to take a physiological dose?

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DISCLAIMER: We recommend speaking with a registered medical practitioner before taking any supplements or vitamins to ensure you don’t encounter any adverse effects or clashes with current medications you may be taking. 


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