November 2021
Written by Eric Suni, Staff Writer
Medically Reviewed by Alex Dimitriu, Psychiatrist

Melatonin, often referred to as the sleep hormone, is a central part of the body’s sleep-wake cycle. Its production increases with evening darkness, promoting healthy sleep and helping to orient our circadian rhythm.

The body naturally produces melatonin, but researchers and the public have increasingly taken an interest in external sources of it, such as liquids or capsules, as a way to address sleep difficulties. In the United States, melatonin is sold as a dietary supplement, and a 2012 survey by the National Institutes of Health found it to be one of the most commonly used supplements among both adults1 and children2.

Studies have found that melatonin can improve sleep in certain cases, but it isn’t for everyone. It is important to be aware of and carefully consider melatonin’s potential benefits and downsides. People who want to use melatonin supplement should also be aware of issues related to dosage and the quality of supplements.

What Is Melatonin?

Melatonin is a natural hormone3 that is produced by the pineal gland in the brain and then released into the bloodstream. Darkness prompts the pineal gland to start producing melatonin while light causes that production to stop. As a result, melatonin helps regulate circadian rhythm and synchronize our sleep-wake cycle with night and day. In doing so, it facilitates a transition to sleep4 and promotes consistent, quality rest.

Melatonin created within the body is known as endogenous melatonin, but the hormone can also be produced externally. Exogenous melatonin is normally made synthetically5 in a laboratory and, as a dietary supplement, is most often sold as a pill, capsule, chewable, or liquid.

Can Melatonin Supplements Improve Sleep?

It is well-established that melatonin produced by the body plays a fundamental role in getting quality sleep, so it’s natural to consider whether melatonin supplements can be used to address sleeping difficulties.

Research to date has shown that melatonin supplements may be useful in certain situations for both adults and children.