Melatonin: The Role it Plays in Sleep

By Sheryl Grassie

Apr 27th, 2022

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Melatonin is a naturally occurring hormone in the brain that helps us fall asleep at night. It is controlled by light and can be increased or supplemented to improve quality of sleep.

What is Melatonin?

Melatonin is a hormone, sometimes called the “pineal hormone” or the “sleep hormone,” which works in conjunction with other hormones like serotonin to control sleep. It is additionally referred to as the “darkness hormone” because our bodies only produce it when it is dark and it can be affected by even small amounts of light.

Although most people naturally produce enough melatonin, for a variety of reasons some people do not. This can result in sleep disturbances. Working to better regulate your melatonin production, or supplementing with synthetic or natural melatonin, are common ways to assist with sleep disorders.

Melatonin can help with insomnia or support better sleep-awake cycles for people who work rotating or night shifts. Melatonin can be used to support a variety of sleep issues related to different disabilities and diseases. It can mitigate the effects of drug withdrawal, help with jet lag symptoms, support sleep cycles while traveling, help with the side effects of cancer treatments, and improve memory loss. Research continues regarding the use of melatonin for a number of additional disorders and conditions.

As a remedy, melatonin is considered safe for short and long-term use, with long-term effects still being studied. It generally does not have side effects like other sleep drugs and does not produce dependence (addiction). The body does not habituate to melatonin causing the need for continual dosage increase.

Melatonin also does not generally leave the user groggy or unfocused as other sleep aids can. In a very small number of cases, there are associated side-effects like headache or nausea, or a feeling of disorientation or depression. The Mayo Clinic warns against using supplemental melatonin with certain other drugs or if you have an autoimmune disorder. Because melatonin makes you drowsy, there is no driving for the first five hours after taking it.

How Does Melatonin Work?

Melatonin is not a sleeping pill and it doesn’t make you sleep, but it does help you fall asleep by putting you into a naturally drowsy state. It acts as an aid, so you can transition to a deeper sleep state. Without enough melatonin, we can have a very hard time falling asleep and many people suffer from insomnia. Now that science better understands how the body produces melatonin, and there are ways to synthetically manufacture it, you can improve your natural melatonin production or supplement it, whichever works for you.

How is melatonin produced?

Melatonin is produced according to our body’s intake of light. The retina in the eye perceives light and dark and sends various signals to the brain. We know that melatonin is produced by the conversion of serotonin. Serotonin, considered one of the “happiness hormones,” is changed into melatonin by the pineal gland, a small pea-sized gland in the brain. In our bodies, protein is converted to tryptophan, then to hydroxy-tryptophan (5HTP), then serotonin, and then melatonin. The melatonin then goes into the bloodstream and makes us sleepy.

The start of this hormone chain, the one that ends in the production of melatonin, happens in relation to lack of light. Our bodies have an internal biological clock that sends out signals based on things in the environment. When light occurs in the morning the brain detects the light and sends signals to the body to wake up, raise its temperature, and speed up its metabolism. It sends out different hormones to accomplish this. The production of melatonin ceases during daylight hours and levels are almost undetectable. When we lose light in the evening the levels increase and signal the body to become drowsy and to fall asleep.

Melatonin disruption

There are numerous ways in which this hormonal conversion chain might be interrupted, causing a decrease in the amount of needed melatonin and disrupting sleep. In a normal, healthy individual the most likely interrupters are lifestyle related, like watching television before bed, not getting sufficient daylight during the day, having irregular sleep schedules, traveling through different time zones, or too much nighttime light exposure.

Regulating with Light and Dark

Prior to about a hundred years ago, human sleep and work cycles were more predominantly dictated by daylight. We worked while the sun was up and slept while it was dark. This is a naturally occurring cycle that our bodies desire to mimic. We innately want to be up and active when the world is light and awake, and to slow down and sleep when the light goes and the natural world is at rest.

So too in the cycle of the year; we automatically sleep more in the winter when there is less light, and we sleep less in the summer when the sun is up longer. In more primitive agricultural societies, this natural rhythm of working and sleeping according to the light was a given way of life.  People worked longer hours during the growing and harvesting seasons and slept less because the light suppressed the production of melatonin and kept people awake. We also were outside more, exposed to more daylight, and this kept our melatonin levels in balance.

The body adapts to the amount of daylight it gets and adjusts its circadian rhythm or 24-hour clock accordingly. The body also adjusts its’ sleep/wake cycles based on exposure to light. For example, if you have no exposure to daylight and work inside all day, then keep yourself exposed to bright indoor light in the evening, the body can become challenged with differentiating when it should sleep. The body produces melatonin just after dark (and only in the dark) and the accompanying drowsiness signals time for sleep. But if your evening environment is relatively bright light right up until bedtime, you may not easily fall asleep because melatonin will not be produced.

It wasn’t until after World War I that electric lights were more universally incorporated into homes and buildings. We gained the freedom to extend our workday and change our sleep patterns. This change was only moderate at first, but over time our work hours and our sleep patterns have changed more and more, and become more irregular. We don’t go to bed when it gets dark or wake up with the sun.

We choose our sleeping and waking schedules based on our lifestyle. We might work varying shifts in a business that runs 24 hours a day. In recent times, we have incorporated into our lifestyles numerous light giving appliances like, televisions screens, computer screens, tablets, and phones, all which require direct eye contact with a form of light. When we use them later in the day, they can confuse our brains and neutralize the production of melatonin when it is needed most, right before sleep.

Aging and Melatonin

One final thought on how melatonin works. It naturally decreases as we age making it harder and harder to sleep as we get older. Many seniors find sleep a challenge and could benefit from melatonin supplementation.

Increasing Melatonin

If you are having difficulty sleeping, and especially if you are older, have a non-traditional schedule, or travel substantially, you might want to look at ways to increase your melatonin. This can be accomplished in two different ways.

  1. First, you can increase melatonin through natural lifestyle adjustments primarily focused on light exposure.
  2. Secondarily you can increase it through supplementation.

Both have pros and cons, but can readily help increase melatonin and improve sleep.

Increasing melatonin naturally

You can increase melatonin and support your circadian rhythm naturally. You need to be aware of your schedule and the amount of light you are getting. Some experts say that having a good night’s sleep begins in the morning. It is recommended that you start by getting up at the same time every day, and preferably with the sunrise. You can use an alarm or even a dawn simulator alarm to get you up and going with the light. Light-based alarms can be easily found on Amazon under “dawn simulator” or “light therapy.”

Once up, you need to think about getting enough daylight, ideally outdoor sunlight, an hour or more in the morning. Change your afternoon walk to the morning, get up and go for a bike ride, have breakfast in a sunny window. This light exposure will decrease melatonin, and help you manage your overall sleep cycle.

In place of sunlight, like on an overcast day, or when the temperatures are too cold to go out, consider a light tray of some kind. Also readily available on Amazon or other online sites, light trays are now small portable devices that simulate daylight. Often used for seasonal affective disorder (SAD) they can help re-regulate your sleep hormones.

In general, natural remedies to increase melatonin production focus on light. How much daylight are you getting during the day, how much artificial light are you exposed to in the evening after dark? If you can increase daylight, especially in the early part of the day, and decrease exposure to electric indoor light for several hours before bed; it will affect melatonin and improve sleep. Lowering lamps, turning off all overhead lighting, reading on a Nook or Kindle in an otherwise dark room before bed, can all help. The goal is to re-train your body’s biological clock to a more natural rhythm with light and dark.

Increasing melatonin with supplements

A second way to increase melatonin is by taking it in a supplemental form. This can be done orally, and it is generally taken about 30 minutes prior to bedtime.

There are a number of different brands and types of melatonin that can be purchased at your neighborhood pharmacy (without a prescription) or at your local health food store. There are natural and synthetic forms of melatonin, sublingual tablets that melt under the tongue and don’t have to be swallowed (great for kids), and time-released versions for better sleep all night.

For children and people who have difficulty swallowing, in addition to the sublingual forms, there are liquid versions, gummies, tinctures, and sprays.

Melatonin is not covered by insurance because it is considered a nutritional supplement. It not regulated by the FDA, and considered a PRN, a remedy that you can take “as needed.” It is, however, fairly inexpensive. When traveling, it is suggested that you start taking melatonin several days before you leave, two hours before bedtime.


Supplementing with melatonin is considered a safe and effective way to improve sleep as long as you keep dosage in an acceptable range. The ubiquitous recommendation is to start with a very low dose (.25 or .5mg) and increase over time. You can raise the dosage by .5mg every three or four days until you reach a level between 1-3mg, something in that range should work well for most people.

There are no reports of fatality due to overdose, however, the recommendation is not to exceed 6mg. If you want to increase beyond that it should be under the supervision of a health care professional. You can find a dose that works for you and supplement with this dose for a few months, then stop and test how you are sleeping without it.

Using it for a period of time can trigger the body’s natural melatonin production, and you may find you can sleep fine without it. If, after several weeks of initially trying melatonin, you don’t seem to be getting results you should discontinue usage.

Related: Can you overdose on melatonin?

Melatonin and Good Sleep Hygiene

Naturally increasing or supplementing melatonin may not be enough and it is recommended that you combine it with good sleep hygiene or sleep practices like:

  • No electronics/screens at least an hour before bed
  • Sleeping in a dark cool room
  • Using light blocking curtains if needed
  • Sleeping on your side
  • Going to bed at the same time every night
  • Skipping naps
  • Having a bedtime routine, like a warm caffeine-free drink, brushing teeth, reading for 10 minutes, going to bed
  • Avoiding alcohol
  • Keeping lights low for several hours before bedtime
  • No television or reading in bed
  • Getting plenty of exercise
  • Spending time daily outside in the sunshine

Side Effects, Warnings and Efficacy

In general, melatonin is considered a very safe remedy. Side effects are rare if it is taken properly and at the correct dosage. Too much melatonin can cause drowsiness the following day and impair cognitive function and in rare cases people report symptoms like nausea, dizziness, or headache. Children seem to tolerate it extremely well.

There are warnings if you are pregnant, or nursing, or have an autoimmune disease; do not take melatonin without medical supervision. If you have a seizure disorder like epilepsy or suffer from depression, you should check with your doctor before starting it. There are a number of medications that can have reactions with melatonin like sedatives and blood pressure medications. Again, check with your doctor before starting melatonin, especially if you are on any prescription drugs.

The efficacy of melatonin is somewhat debated. Research is conflicted about how well taking supplemental melatonin really works. Some tests, where participants were given a placebo, indicated melatonin did not improve sleep; whereas other tests have indicated good results.

Melatonin is used by a large number of people (the Centers for Disease Control and Prevention (CDC) have estimated that over 3 million people in the United States are taking melatonin and the number is increasing) and until there are more clinical trials, anecdotal evidence and self-trial may be your best bet.

Disability, Disease and Sleep

Melatonin is successfully used to help regulate sleep with a number of disabilities and disorders that have sleep associated challenges like insomnia. In particular, both children and adults who are blind and experiencing circadian rhythm sleep disorders are helped by using melatonin. It is routinely recommended for individuals with attention deficit hyperactivity disorder (ADHA) and has become commonplace for use with autism.

Further, there is evidence that it is helpful with a wide range of developmental disabilities that have insomnia as a comorbid factor. The insomnia associated with cerebral palsy and traumatic brain injuries (TBI) are helped by melatonin, and mental health conditions like bipolar. It is also popular for use with physical maladies like restless leg syndrome and chronic obstructive pulmonary disease (COPD).

Research and Melatonin

Supplemental melatonin lives in an interesting middle ground between a prescriptive medicine and a dietary supplement. It is a natural hormone that is accepted and recommended by both physicians and natural health practitioners, and anecdotally at least, it seems to be effective for sleep problems associated with a wide range of disorders.

It is not linked with any serious side effects, and research supports short-term use without concerns. There is, however, no real data on long-term usage and outcomes. Longitudinal studies are one area of recommended research regarding melatonin.

Further, with limited studies, there is a caution about over generalization. For example, one study found that melatonin increased the symptoms of rheumatoid arthritis and a conclusion was drawn that melatonin was not good for autoimmune diseases. More research needs to be done in a number of areas before definitive claims can be made one way or another. Currently, there is not enough scientific evidence to substantiate claims about the efficacy of supplemental melatonin or the long-term effects.

Other Beneficial Effects

Since melatonin is a naturally occurring substance in the body, we do know some of the supportive roles it plays, and how it supports better health overall. In addition to inducing sleep, it can also relieve symptoms associated with some medical conditions and is showing great promise for help with withdrawal from certain drugs. We know that melatonin:

  • Is a strong antioxidant
  • Is an anti-inflammatory
  • Supports immune health
  • Supports eye health
  • Helps treat stomach ulcers
  • Helps relieve heartburn
  • Regulates fat cells
  • Mitigates the effects of radiation
  • Helps with withdrawal from drugs in the Benzodiazepine class
  • Helps with nicotine withdrawal
  • Supports memory function
  • Reduces mouth sores from radiation
  • Eases or alleviates ringing in the ear (tinnitus)


Melatonin is a hormone called the “sleep hormone,” that is produced in the brain and that plays a critical role in helping us fall asleep and stay asleep. The amount of melatonin we have is dependent on our exposure to daylight and darkness and happens from a chain reaction of hormones that result in melatonin.

It is important to remember that melatonin is only produced when the body experiences darkness and that this production can be disrupted by even small amounts of light. When light interferes, melatonin levels can become too low, causing a lack of drowsiness and making it difficult to transition into sleep. This causes a need to increase our melatonin levels. We can do this naturally through adjusting our exposure to light and dark, or through taking a melatonin supplement.

If using supplementation, the amount is usually determined on an individual basis, through increased trial dosage. Melatonin comes in lots of forms, like liquid or gummies, for ease of ingestion. Supplementation is especially popular for travel when sleep schedules, and light and dark conditions, may be altered from the norm. Melatonin only has rare side effects that are not serious or life-threatening, and it is widely endorsed for short-term use. Long-term use is still being studied along with effectiveness. Melatonin’s popularity would support the need for more research studies.

Melatonin seems to have a positive effect on sleep disturbances associated with a number of disabilities and disorders like autism and TBI, as well as more short-term conditions like jet lag. Melatonin also has numerous health benefits for our bodies like reducing inflammation, acting as an antioxidant, and helping us properly regulate the production of fat.

Sometimes to improve sleep, we need to combine increased melatonin with good sleep hygiene practices like “no screen time” before bed, more exercise, no alcohol, and more exposure to sunlight during the day.

Overall, increasing melatonin is an excellent way to ensure improved sleep. It works with the body’s natural hormone production in maintaining our biological clocks. In contrast to narcotic sleep aids, melatonin appears safe with little or no side effects and is an easy and inexpensive way to support better sleep.