Melatonin
Melatonin is a hormone made by the pineal gland in the brain, mainly at night, and is part of the body's sleep-wake rhythm. Supplements contain synthetic melatonin.
Also listed as N-Acetyl-5-Methoxytryptamine, Melatonine, Melovine, Melatol
The average improvement is modest
A 2013 analysis of 19 trials involving 1,683 participants with primary sleep disorders found sleep began about seven minutes sooner and lasted about eight minutes longer than with placebo. Sleep quality also improved slightly. The pooled results describe an average across studies, not a promised response for every restless sleeper. 1
Timing is part of the treatment
A 2024 analysis of 26 randomized trials found that dose and administration time influenced the observed sleep effects. Its dose-response modeling is useful for research, but does not establish one best bedtime dose for everyone. 2
Persistent insomnia needs a broader answer
NCCIH summarizes guidelines that recommend cognitive behavioral therapy for insomnia as initial treatment and find insufficient evidence to recommend melatonin for chronic insomnia. This does not erase the modest trial benefits; it puts them in the context of treating an ongoing sleep disorder. 3
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Sleep3 effects
Stress & Mood3 effects
No study is linked to this rating.
No study is linked to this rating.
No study is linked to this rating.
All studies
7 publications are linked to Melatonin, newest first.