dreamt’s little guide to melatonin

by Jannise Babbush, PhD
April 18, 2020

One hundred white melatonin sleep aid pills scattered on a light blue table

In this blog post, dreamt’s Dr. Jannise Babbush explains what melatonin is, how it works and why it helps your sleep. 


Sleep is vitally important for your physical and mental health. It plays a major role in the restoration of the body and mind. While you’re getting those precious ZZZs, your brain is actively cleaning out what’s not needed while it organizes the information that is [1]. These processes are critical for learning, memory, and more generally give us a general sense of well‐being during the day.  

However for some, maintaining healthy sleep isn’t easy. More than 1 in 3 people in the US report experiencing sleep issues [2]. Our ability to sleep is dependent on a variety of factors such as our diet, our intake of caffeine, light exposure, our consumption of alcohol and our levels of stress (which tend to be through the roof). Even when you’ve optimized your habits for better sleep there may be other underlying factors wreaking havoc on your body’s sleep-wake cycle. 

Sleep is orchestrated by neurochemical processes which shut down day time activities and turn on sleep‐promoting centres in the brain. Melatonin is the main chemical involved in this process. You may have heard of melatonin. It’s a very common supplement that is available at pharmacies. But many people don’t really know what melatonin is, how it works and why it is crucially important for maintaining healthy sleep habits.

Let us explain!

What actually is melatonin?

Melatonin is a molecule secreted in the brain by the pineal gland in response to darkness. 

Melatonin is the reason you begin to feel drowsy after the sun goes down. It’s production begins when your eyes detect the change from light to darkness and send a signal to the brain’s pineal gland to start producing melatonin. Like other hormones, melatonin delivers important messages to your body. Melatonin’s main message is that you need to sleep and it’s most important function is regulating the circadian rhythms of several biological functions including controlling the sleep-wake cycles [1].

Melatonin’s synthesis begins with tryptophan (you know, that molecule we always blame for our sleepiness after eating a big thanksgiving turkey dinner) which is transformed into serotonin, and, finally, to melatonin [3]. The transformation of serotonin into melatonin is stimulated by darkness and inhibited by light. This explains why melatonin production begins soon after sundown, peaks in the middle of the night (between 2 and 4 in the morning), and decreases gradually during the second half of the night. The smallest amount of light reduces the production of melatonin, which explains why we begin to wake up when the sun rises, or why some folks can only sleep in complete darkness.

Melatonin has many physiological functions in addition to sleep. It’s a potent antioxidant which helps the body detoxify free radicals [4]. It also plays a role in bone formation, skin protection, and the immune system. Substantial research over the years suggests that melatonin has a number of benefits, with particular efficacy for jet lag, depression, and insomnia [5,6]. 

What happens when things get out of whack? 

When it’s dark, melatonin signals to the body that it’s time to start winding down. Any changes to your environment (i.e. travel, shift work) or to the molecules that play a key role in melatonin’s production (i.e. from stress, depression, aging, certain drugs (e.g. β‐blockers, clonidine, naloxone and non‐steroidal anti‐inflammatory drugs (aspirin, ibuprofen and acetaminophen)) can desynchronize your normal cycle or even worse, halt the nocturnal production of melatonin [1]. For example, since melatonin is produced in the brain from serotonin, a depletion of serotonin due to stress and anxiety prevents healthy sleep by reducing the melatonin available in the brain. 

In short, the depletion of melatonin production can make it difficult to fall asleep or wake up at the desired time. 

How melatonin works as a supplement

Melatonin, when taken as a supplement, can help reset the body’s sleep-wake cycle. This is useful for those who want to fall asleep faster and/or stay asleep longer without resorting to prescription sleep medications. In a meta-analysis study that included 15 studies of patients with only insomnia, melatonin treatment was shown to significantly reduce the time it took people to fall asleep and it also increased sleep quality and duration [7]. Furthermore, melatonin has few side effects and it doesn’t cause withdrawal or symptoms of dependence unlike benzodiazepines and z-drugs such as Zolpidem (better known by its brand name Ambien) [8].

Melatonin can be delivered in a variety of ways: it can be taken orally, as a sublingual tablet, as a slow release pill, or even inhaled. How you consume melatonin affects how it works. 

The most common method of ingesting melatonin is orally, as a pill. When taken orally, the effects take a while to kick in (60-120 mins) and often vary from person to person and even from night to night. This is because melatonin has to go through first pass metabolism in the liver, which greatly reduces the bioavailability (i.e. the amount that reaches your bloodstream so it can have an effect). Studies have shown that despite taking the same oral dose, there are wide ranges in the peak concentration of melatonin in the blood as well as the bioavailability, which can range from 3-56% [9-10]. What this all means is that for a typical dose, let’s say 3-5mg, only a fraction of it is going to have an effect and the rest of it is broken down by the liver. That active fraction changes depending on your diet, activity level, age, etc. So 3mg may feel like way more or way less. This explains why the same dose may work well one night and not the other.

In order to get a more consistent experience, melatonin can also be inhaled.

Can you vape melatonin?

Yes. Melatonin can be inhaled using a vaporizer pen. 

Taking melatonin this way has a number of key benefits. 

Inhalation of melatonin gives users a predictable and effective dose that taking melatonin orally does not. Using this delivery method allows for rapid absorption of the ingredients making it one of the fastest-acting sleep aids available. 

This is because the majority of the dose delivered to the lung is immediately absorbed and available systemically. This means you can limit the amount of melatonin needed to have the same effect. Also, since it’s delivered directly to the bloodstream it can be taken right at bedtime and is immediately effective. When taken orally melatonin should be ingested two hours before bedtime. 

Melatonin’s antioxidant properties have also been shown to protect the lungs against such things as lung fibrosis and even reverse the damage due to scar tissue [12].


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