Does Melatonin Work for Sleep?
Many people struggle to fall or stay asleep. And for an increasing number of Americans, the way to fight back is with over-the-counter melatonin supplements.
An analysis by the Journal of the American Medical Association published Feb. 1, 2022, suggested that between 2000 and 2018, the percentage of people using melatonin in the U.S. rose from 0.4% to 2.1%, with most of the jump occurring after 2009.
The trend is alarming to some experts since melatonin isn’t a one-size-fits-all sleep aid. “It is a misconception that melatonin is an effective sleeping medication. Rather, it is a circadian trigger that helps regulate the sleep-wake cycle,” notes Dr. Colleen Lance, a sleep specialist at Cleveland Clinic.
Even in the right circumstances, melatonin use comes with some risks.
What Is Melatonin?
Melatonin is a natural brain chemical that’s sometimes called a “darkness hormone.”
“When the sun goes down, there is a small burst of melatonin that initiates a neurohormonal cascade to prepare you for sleep a few hours later,” Lance says.
Once asleep, melatonin levels rise, peak, and eventually fall as the sun rises in the morning.
Melatonin supplements aim to have the same effect. They contain a synthetic version of melatonin, available in pills in varying doses – such as 1, 3, 5, or 10 milligrams.
Melatonin supplements are also sold in the form of gummies, tinctures (drops), or patches. You can even find sleep “cocktails” or combinations of supplements that include melatonin and other herbs that may promote sleep (such as valerian root), either in pills or droplets.
Who Might Benefit From Melatonin Supplements?
Melatonin supplements are typically recommended for people struggling with a circadian rhythm – or sleep-wake cycle – that’s out of sync. That person could be:
- Someone working the night shift who has trouble sleeping during the day (shift work disorder).
- Someone coping with jet lag after flying in from another time zone (jet lag disorder).
- A high school student who is going to sleep too late at night.
“The goal of using melatonin is to shift the patient’s sleep onset to a more acceptable time. For patients with jet lag, this may be very different than for a high school student who needs to fall asleep earlier,” says Dr. Melissa Bernbaum, director of epilepsy and ambulatory sleep medicine at Northwell Health’s Huntington Hospital in Huntington, New York.
Melatonin is also used for sleep challenges such as:
- Delayed sleep phase syndrome. In this condition, a person’s natural sleep time is delayed by a few hours. So instead of falling asleep at 11 p.m., the person typically falls asleep at 1 a.m. and then wakes up later as a result.
- Irregular sleep-wake rhythm disorder. The condition occurs in people who sleep numerous times within a 24 hour period, such as people who are confined to bed due to chronic illness.
Taking small amounts of melatonin is generally considered safe. It’s not habit-forming and it has no withdrawal symptoms when you stop taking the supplement, even abruptly.
Still, melatonin use isn’t without risk.
The Food and Drug Administration classifies melatonin as a dietary supplement. Unlike prescription medications, supplements are not tested for quality or safety before they land on store shelves. That means:
- You won’t know if other ingredients are in melatonin supplements. Manufacturers may or may not include that information on packaging.
- You can’t be sure exactly how much melatonin a supplement contains – if any – despite marketing promises on packaging. Some evidence suggests that melatonin supplements can contain as much as 478% more of the hormone than what’s listed on the label. “Studies of the commonly found formulations show a lot of variables of the actual amount of melatonin present between manufacturers, and even variation batch to batch from single manufacturers,” Lance says.
As melatonin intake increases, so does the risk for side effects. “Concerns would be for increasing sedation even during the day. In trials, it has been used in combination with other medications as part of general anesthesia, so it’s not to be taken lightly,” Lance warns. “Other side effects can include headache, nausea, vomiting, and dizziness.”
Some other concerns about melatonin:
- It may interact with certain medications, such as those to treat high blood pressure or diabetes.
- It’s unclear if melatonin is safe for use in breastfeeding or pregnant women.
Melatonin is usually recommended for short-term use, just long enough to shift your sleep schedule and get back in sync with your circadian rhythm. “But patients sometimes take it chronically or intermittently without negative consequences,” says Dr. Melanie Pogach, sleep medicine and pulmonary critical care specialist and director of Chronic Respiratory Failure Management at St. Elizabeth’s Medical Center in Boston.
Just make sure to talk to your doctor before taking melatonin supplements, since the dosing and timing of melatonin depend on your sleep condition.
For example, Pogach recommends very low-dose melatonin – 0.3 to 0.5 milligrams – for delayed sleep phase syndrome. “Together with proper light and dark conditions, low-dose melatonin taken two to three hours before the goal bedtime can help to pull sleep earlier,” she says.
Will It Work?
Studies about melatonin’s effectiveness are mixed.
“In my experience, many patients who present to sleep medicine for evaluation report that they have tried melatonin and found it ineffective,” Pogach says. “This is likely because the expectation is that melatonin will fix insomnia and strongly induce sleep. That is not what melatonin does, however.”
Your own melatonin levels may also determine how effective the supplement is.
“When melatonin is taken during a person’s biological day when one’s own melatonin levels are low, melatonin has transient and rapid ability to promote sleep. Sleep-inducing effects are much less consistent when melatonin is taken after a person’s own melatonin rise,” Pogach says.
What Else Will Help?
Remember that no single pill will fix a sleeping problem.
You’ll need to address underlying health conditions or perhaps scheduling challenges that may be causing your sleep issues. You should also practice a regular routine of good sleep habits, such as:
- Going to sleep and waking up at the same time each day.
- Exercising earlier in the day instead of right before bedtime.
- Avoid long naps in the daytime.
- Limiting caffeine intake.
- Avoid food and alcohol intake late in the evening.
- Limiting exposure to blue light (from electronic devices such as smartphones and TVs) at night.
- Creating a comfortable sleep environment that is dark and not too warm.
Other therapies, such as cognitive-behavioral therapy for insomnia, may also help you get some rest.