Melatonin and Insomnia: What Science Says About the Use of Melatonin Supplements


Melatonin pills. Melatonin is a hormone naturally produced within your body to control your sleep cycle. 

You have probably come across melatonin supplements when browsing your local pharmacy. They claim to be a safe way to get better sleep at night, and more and more people are reaching to the shelves to give it a go. But do they actually work? Here is what the science says about using melatonin to aid in sleep.

What is Melatonin?

Melatonin is a hormone naturally produced within your body to control your sleep cycle. The onset of darkness triggers melatonin production, explaining why you get tired at night and get through the day even after sleeping poorly. As you get older, you produce less melatonin, so you need less sleep.

Is Melatonin Safe?

As melatonin is a natural hormone, many assume it is a perfectly safe treatment for sleep disorders. However, the levels found within supplements are often higher than what your body would typically produce.[1] While short-term use seems safe, there are possible side effects such as dizziness or headache. It is also possible that supplements could cause problems by interacting with other medications, so it’s best to speak to your doctor before starting melatonin capsules.

There is also a concern relating to the purity of supplements. The actual concentration is often unknown in regions like the US, where melatonin is not regulated. A study conducted in 2017 found that out of 31 melatonin supplements, the actual content varied between 83% less and 478% more than what was on the label.[2]

When to Use Melatonin

Melatonin supplements work by altering your biological rhythm. They do not make you more tired by inducing sleep, but they regulate when your body begins to feel tired.[3] For this reason, melatonin is not suitable for treating insomnia when your body is tired, but you can not sleep.

However, there are other areas in which it can be of use. If you have an irregular sleep pattern or any disorder that affects your circadian rhythm, melatonin can help solve these problems. They may help if you work night shifts and need to sleep during the day when your melatonin level is naturally low. There is also a suggestion that melatonin may help children on the autism spectrum sleep more regularly, but this is so far inconclusive.[4]

The bottom line is that melatonin supplements are probably not the answer to insomnia. However, for other disorders, they may help to regulate your sleep. As with any supplement, it is your choice, and if you do decide to take it to aid in sleep, it is unlikely to do much harm. Although, you should always consult your doctor first to ensure it won’t interact with any other medications you might be taking.


“The Safety of Melatonin in Humans” by Lars Peter Holst Andersen, Ismail Gögenur, Jacob Rosenberg and Russel J. Reiter, 21 December 2015, Clinical Drug Investigation.
DOI: 10.1007/s40261-015-0368-5

“Melatonin Natural Health Products and Supplements: Presence of Serotonin and Significant Variability of Melatonin Content” by Lauren A.E. Erland, MSc
and Praveen K. Saxena, PhD, 15 February 2017, Journal of Clinical Sleep Medicine.
DOI: 10.5664/jcsm.6462

“Clinical Practice Guideline for the Pharmacologic Treatment of Chronic Insomnia in Adults: An American Academy of Sleep Medicine Clinical Practice Guideline” by Michael J. Sateia, MD, Daniel J. Buysse, MD, Andrew D. Krystal, MD, MS, David N. Neubauer, MD and Jonathan L. Heald, MA, 15 February 2017, Journal of Clinical Sleep Medicine.
DOI: 10.5664/jcsm.6470

“Melatonin for Sleep in Children with Autism: A Controlled Trial Examining Dose, Tolerability, and Outcomes” by Beth Malow, Karen W. Adkins, Susan G. McGrew, Lily Wang, Suzanne E. Goldman, Diane Fawkes and Courtney Burnette, 10 December 2011, Journal of Autism and Developmental Disorders.
DOI: 10.1007/s10803-011-1418-3

17 Comments on "Melatonin and Insomnia: What Science Says About the Use of Melatonin Supplements"

  1. Clyde Spencer | May 17, 2022 at 10:59 am | Reply

    “As you get older, you produce less melatonin, so you need less sleep.”

    Shouldn’t that be “you feel less need for sleep” or “have less desire for sleep?” It is an entirely different question, which the article didn’t address, as to whether to there is less need for sleep to maintain good health.

    • Alistair Goodwin | July 28, 2023 at 8:24 pm | Reply

      Great observation which I would like answered. Having such an ambiguous statement at the beginning of the article really calls into question its validity

  2. Talked about Melatonin, but never mentioned daily safe prescribed dose, just like vitamins or minerals. Is it 3 mg or 5 mg or 10 mg?

    • I found that I got a hangover being sleepy and groggy when I woke up with just 3mg. I take only 1mg and if I’m still awake 2mg or a 3rd pill for a total of 3mg. I’d recommend starting out at lower dosages. Also, my preferred aid is tryptophan (which is in Turkey that puts you to sleep). So when I’m having sleep issues or wake up wide awake at 2am, I reach for one or both. L-Tryptophan 500 mg, Encourages Positive Mood*, Supports Relaxation*, 120 Veg Capsules on Amazon.

  3. Exogenous melatonin effects blood clotting and it is recommended to be discontinued at least 2 weeks prior to a surgical procedure.

  4. I took meletonine 5mg to start. I then syarted using 10 mg under my dr’s advise.when it no longer helped I stopped

  5. Yet doctors tell parents they can give thier kids melatonin. Knowing They’ll most likely abuse it and with how varied doses are from the labeling… Since when did popping a pill stand in for actually learning to parent and put kids to sleep. I was 18 and did it by learning how and didn’t have a cell phone to look at all the time either…. Then parents winder why kids don’t go to sleep. First they don’t control those automatic processes and most importantly it screws up thier sleep cycle by desensitizing the brain to it leading to children awake and maybe even suffering side effects as parents cry like they did things right.

  6. Obviously never heard of Doris Loh researcher on Melatonin, which is in many plants naturally and its biological pathways not only in sleep cycles..

  7. Robert Brookes | May 27, 2022 at 5:48 am | Reply

    I disagree with, that as you grow older, you need less sleep, because the body produces less Melatonin. That simply can’t be right, because other experts say, insufficient sleep increases chances of early dementia. It’s all so confusing.

  8. I would use this article as a guideline, if I considered using melatonin. List to your body & results, do what is best for u. There are many studies, do the research & decide with your dr and move forward. I’m always looking for natural aid instead of pills. The study is what it is, until the next one.

    • I am frustrated about the same inaccurate information about melatonin being shared in articles, even in scientific reviews. The following statements in the second paragraph are either incorrect or totally inaccurate or both:

      “Melatonin is a hormone naturally produced within your body to control your sleep cycle.”
      The first part of that statement is accurate. Melatonin is produced and secreted by the pineal gland. The pineal gland is located near the middle of the brain near the thalamus/third ventricle. The last part of that statement is not correct. Melatonin does not control the sleep cycle. I am not sure what that means, “controls your sleep cycle”. In humans, the timing of Melatonin secretion just happens to occur when we would typically go to bed after the sun goes down; we are diurnal, so we are mostly active/awake during the day and tend to be at rest/asleep during the night. The timing of wake and sleep are governed by the interaction of two separate systems (the circadian timing system and sleep/wake homeostatic system), not the pineal hormone melatonin. Not sure how one hormone could control something so complex. Except for a recent scientific article (RE: a receptor on a orexin neuron) there are no melatonin receptors on any neurons in the sleep centers in the brain stem. There are receptors on subset of neurons that collectively with other neurons make up the suprachiasmatic nuclei in the hypothalamus (brain location of the circadian timing system that influences the timing of the biological/physiological in the body, including melatonin secretion).

      “The onset of darkness triggers melatonin production, explaining why you get tired at night and get through the day even after sleeping poorly.”
      This statement is completely inaccurate. The onset of darkness does not trigger melatonin secretion. The circadian timing system (the suprachiasmatic nuclei [SCN] in hypothalamus) triggers melatonin secretion. Ocular (eye) exposure to white light of sufficient brightness can suppress (stop) melatonin secretion, therefore being in (sleeping in) a dark room (eyes closed) is the most favorable condition for allowing the pineal gland to secrete melatonin when triggered by the SCN. But darkness doesn’t trigger it. Melatonin secretion only occurs for an ~10-hour period (during the night) once every 24 hours. The daily timing of your exposure to light (14-16 hrs) and darkness (8-10 hrs) over the 24-hr day will influence your internal circadian timing system, which will then influence the timing of your melatonin secretion (e.g., people living in Australia or China [a >12 h difference in clock time] secrete melatonin during their night, which would be daytime in North America). I should also note, like humans, rodents (rats, mice, hamsters) have a pineal gland and secret melatonin at night (during dark phase of the 24-hour day). Humans are considered diurnal animals, meaning we are mostly active/awake during the day (light phase) and at rest/sleep during the night (dark phase). Nocturnal rodents are mostly active/awake during the night and mostly at rest/asleep during the day…… humans and nocturnal rodents both secret melatonin during night. Nocturnal rodents are awake during the time that they are secreting melatonin.

      “As you get older, you produce less melatonin, so you need less sleep.”
      This statement is not accurate either. There are data that support and data that do not support the conclusion that we produce less melatonin as we age (e.g., peak melatonin levels at 20 yrs old vs peak melatonin levels at 70 yrs old). Researchers typically have only compared the melatonin levels between a group of young subjects (e.g., 18-35 yr olds) and a group of elderly subjects (65 yrs old and older), but I know of no study that has measured melatonin levels in a group of individuals from their youth through young adulthood and middle age up to their elder years and showed that their average melatonin secretion levels decreased over their lifespan. There has been research conducted in populations of different rodents; in those studies an age-related decrease in melatonin levels was observed.
      If given 10 hours opportunity to sleep each night, a healthy, young individual with no sleep problems and sleep disorders could sleep on average, 8-10 hours within that 10-hr opportunity. If given the same 10-hr opportunity to sleep each night, a healthy, elderly individual with no sleep problems and no sleep disorders would sleep less than 8 hours within that 10-hr opportunity. Researchers do not know why the average duration of sleep per 24 hrs in elderly (65 yrs and older) people tends to be shorter than that of young (less than 35 yrs old) people. Researchers are trying to determine whether the shorter duration of sleep in elderly people reflects (a) less physiological need for sleep over 6-8 hours or (b) there is a physiological need to sleep greater than 6-8 hours, yet the sleep centers in the brain stem are not capable of promoting sleep durations over 6-8 hours. I don’t believe researchers have attributed lower melatonin levels as the cause of shorter sleep duration observed in elderly people compared to young people, especially since an age-related decrease in melatonin levels has not been unequivocally been proven. It should also be noted that elderly individuals typically experience lighter sleep, meaning, they have a tendency to wake easily from sleep in response to the slightest sound; this is the case, particularly during non-REM slow wave sleep (the deepest stage of sleep).

  9. I take 5mg Vitafusion melatonin gummies and about 10 minutes later start to feel very sleepy and sleep through the night they’re great. The only side effect is if I don’t get a full 8 hours I wake up feeling a bit groggy but it goes away quickly.

  10. I use 30mg most nights- and it has helped. My Dr was not concerned about my dosage, except to say not to take more than 40. 6 months in, and I’ve had no issues. Nor do I feel groggy or sleepy when I awake- as I did with prescription meds.

  11. I have used melatonin for 25 years… 3 or 4 3mg tabs, and have NEVER experienced dizziness or headaches, so I see these side effects reported all the time. Not me. The original studies done 30 yes ago showed that it increased REM sleep, boosted the immune system due to better sleep, and boosted longevity in mice. Pre-melatonin prior to 1997 for me was a sleep “nightmare’s with poor sleep and sick with colds 3x per winter. After melatonin was and has been marvelous. I don’t agree with this article.

  12. No more than 3mg to help my kids on the spectrum fall asleep within 30 min as opposed to 90 min, with fewer middle of the night wake-ups, has greatly helped. I was reluctant at first, but my pediatrician said my children will suffer more in not getting enough sleep than from any potential side effects from melatonin. So far so good.

  13. I took melatonin for a short while. Adter 3 days,I had Extreme reactions to it. At the 3 day point I Couldn’t stay awake!
    Scared the Bajesus out of me. Obviously I immediately stopped taking it. Took almost 3+ weeks after stopping it use Before I started to Feel anywhere near Normal.!

  14. Terrie J Johnson | May 29, 2022 at 8:37 pm | Reply

    I don’t feel medical sciencetis are telling us the truth about anything one day it’s good for us then it’s bad make up your flipping minds just tell us the truth from the start many people read this crap and live their lives by it stop playing with people just for views or likes or thumbs up or whatever it is that gets you off lies lies and more lies

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