Melatonin For Sleep: When It Works, When It Doesn't & Other Options

While many people know it as a sleep aid, melatonin is first and foremost a hormone that our bodies produce to keep our sleep-wake cycles on track. When consumed as a low-dose supplement, melatonin may help sleep in some cases, but it won't necessarily prove effective for everyone.

"Melatonin plays a key role in regulating our circadian rhythm," explains Shelby Harris, PsyD, DBSM, a behavioral sleep doctor and the author of The Women's Guide to Overcoming Insomnia. "The pineal gland is inactive during the day, but as the sun goes down, it activates and naturally produces melatonin to help induce sleepiness. About two hours before you naturally awaken in the morning, melatonin production slows and you begin to slowly awaken."

David Kennaway, Ph.D., the research program leader of the Circadian Physiology Group at The University of Adelaide in Australia, adds that while regulating circadian rhythm is one of melatonin's jobs, it isn't the only one. The hormone also plays a role in cardiovascular function1, blood sugar2, immunity3, reproductive health, hormonal health, and a number of other processes in the body.

Seeing as it's such a powerful and all-important hormone, Kennaway notes that melatonin is not marketed as a supplement in most countries outside the U.S. and Canada. It's only available as a prescription—and one that is only intended for short-term use in adults.

Melatonin's main job is sending the signal that it's time for bed. As such, Harris has seen melatonin supplements be most effective for those looking to adjust to bedtimes their bodies are not used to (when acclimating to a new time zone or trying to become less of a night owl, for example).

For these purposes, she says melatonin is best consumed in low doses (0.5 milligrams to 1 milligram) in the 30 to 60 minutes leading up to your intended bedtime. "If you're taking more than 3 to 5 milligrams nightly, then melatonin isn't likely for you. There's just no data suggesting that more than [0.5 milligram to 1 milligram] is indicated for sleep issues, and sometimes more is just more," she notes.

When taken on a nightly basis, there is limited evidence5 that melatonin will improve sleep quality. While it may make it easier to fall asleep slightly quicker, Kennaway notes it won't necessarily make it easier to stay asleep or reach deep sleep stages. All this to say: If melatonin has not worked quite as you wanted it to in the past, you wouldn't be alone.

Kennaway notes that he's seen many people expect melatonin to make up for bad habits like eating heavy meals or drinking alcohol too close to bedtime, using electronics late at night, and keeping an inconsistent bedtime—which it definitely cannot do.

"It can help some people, but it isn't the cure-all for everyone that it frequently is thought to be," Harris echoes.

All other sleep supplements are like melatonin in that they can't make up for poor sleep hygiene. Nor can they treat recognized sleep disorders like insomnia. Instead, they are meant to serve an adjunct—supplementary—role in an otherwise healthy nightly routine.

If you've already cleaned up your sleep routine and are looking to further support your sleep with a non-melatonin supplement, there are a few key things to look out for.

For starters, look for ingredients that have been studied in humans, backed by sleep-relevant science, and dosed properly. Fillers like binders; preservatives; artificial colors, flavors, or sweeteners; as well as allergens like gluten, eggs, dairy, or soy are best avoided and often unnecessary.

Be wary of any claims that a supplement can treat sleep disorders. Not only do dietary supplement regulations forbid that, as Harris and Kennaway both note, but those with sleep issues that are getting in the way of their lives will want to see a doctor who can set them up with a regimen that may include lifestyle adjustments, cognitive behavioral therapy, other remedies, or a combination of these strategies.

Melatonin is a hormone that our bodies produce around bedtime, and it doesn't necessarily translate to nightly use as a sleep-promoting supplement. If you have tried taking melatonin in the past to no avail, clean up your sleep regimen and consult your doctor if you suspect a larger issue could be at play. For those without underlying conditions, trying one of these non-melatonin sleep aids may also be helpful.*