What is melatonin?
melatonin
Melatonin is a hormone that regulates sleep-wake cycles, though its role is often misunderstood. As of October 2025, sleep researcher Michael Grandner noted that some melatonin supplements contain up to 100 times the labeled amount, and that melatonin itself has no sedating properties. In July 2026, Andrew Huberman explained that managing cortisol levels can set the stage for melatonin increase, while Jonathan Wolf argued that sleep medications, including melatonin, are ineffective and have side effects.
How it developed
- Oct 2025 - Michael Grandner said some melatonin supplements contain 100 times more melatonin than labeled.
- Oct 2025 - Michael Grandner stated melatonin has no sedating properties whatsoever.
- Jul 2026 - Andrew Huberman said that ensuring low evening cortisol sets you up for an increase in melatonin.
In the evidence
Every line below is attributed to a named speaker.
Why melatonin rarely treats insomnia: melatonin has no sedating properties and only signals circadian timing; when insomnia stems from conditioned arousal, a timing signal cannot overcome excess activation.
“It has no sedating properties whatsoever.”Michael Grandner · 6 Oct 2025
Some OTC melatonin supplements contain up to 100 times more melatonin than stated on the label.
“Some of them have like 100 times more melatonin that's actually what's on the.”Michael Grandner · 6 Oct 2025
Melatonin does not meaningfully help general insomnia. A meta-analysis found benefit only for circadian rhythm disorders such as delayed sleep phase, not for typical insomnia complaints.
“There was a metaanalysis for looking at melatonin in insomnia beside you know not related to being a night owl and it probably doesn't help them very much.”Yo-El Ju · 6 Mar 2026
High morning cortisol, driven by bright light, caffeine, or exercise, suppresses evening and nighttime cortisol and thereby enables robust melatonin production for sleep.
“If your morning cortisol is high and you can make it higher doing any number of the things I just It ensures that your evening and nighttime cortisol is low and that's what sets you up for an increase in melatonin.”Andrew Huberman · 22 Jul 2026
Jonathan Wolf delivers a sweeping dismissal of all sleep medications.
“All of the medications made, whether it's Ambien or Halcion or melatonin, don't work. So stop taking them, by the way. Just They have side effects. And so sleep medication doesn't work. None of them.”Jonathan Wolf · 16 Jul 2026