Melatonin and Sleep
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.
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 The.
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.
Melatonin in Adults
In adults, research studies have found the clearest potential benefits from melatonin are for people who have sleeping problems related to Delayed Sleep-Wake Phase Disorder (DSWPD) and jet lag.
DSWPD is a circadian rhythm disorder in which a person’s sleep schedule is shifted later, often by a matter of hours. For people with this “night owl” schedule, it can be hard to get enough sleep if they have obligations, such as work or school, that force them to wake up early in the morning. Studies have indicated that low doses of melatonin taken before the desired bedtime can help people with DSWPD adjust their sleep cycle6 forward.
Jet lag can occur when a person travels rapidly across multiple time zones, such as on an intercontinental flight, because their body’s internal clock becomes misaligned with the local day-night cycle. Evidence from small research studies points to melatonin supplements as potentially helping to reset the sleep-wake cycle 7and improve sleep in people with jet lag.
Shift workers — people who work during the night — often struggle with sleep difficulties related to a misaligned circadian rhythm. Studies of melatonin in shift workers have had inconclusive results, although some people report a benefit.
There is debate about whether melatonin is beneficial in otherwise healthy adults who have insomnia, a persistent condition marked by trouble falling asleep or staying asleep. The existing research is not conclusive. Some experts reviewing it find some evidence in favor of melatonin8 while organizations like the American Academy of Sleep Medicine (AASM) have concluded that there is not sufficient scientific support9 for melatonin in reducing insomnia.
