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Hormone

Melatonin

A hormone that regulates the sleep-wake cycle and supports circadian rhythm alignment.

Evidence gradeCross-checked · High
A+
WeakModerateStrong
4.5/ 5 rating

KÖGN Health grades Melatonin as A+ (Strong evidence) and rates it 4.5 out of 5.

Last reviewed · June 2026

CategoryNatural · Hormone
AvailabilityOTC

Primary effects

  • Improved sleep
  • Circadian rhythm regulation
  • Recovery support

How it works

Signals the body to prepare for sleep, regulating circadian timing and recovery processes.

Overview

Melatonin is one of the most well-researched sleep-regulating compounds. It is particularly effective for sleep onset difficulties and jet lag, as it helps reset the body’s internal clock. While it is generally safe for short-term use, long-term daily use may reduce natural endogenous production in some individuals. It is best used strategically rather than as a permanent sleep dependency solution.

Related ingredients

Graded entries that target the same cognitive goals.

Categories

Natural NootropicsSleep & RecoveryNeuroprotection & LongevityHormonal SupportDaily Foundational NootropicsOver-the-Counter (OTC)High Evidence

Educational information, not medical advice. The evidence grade is KÖGN’s editorial assessment of published research, not a health claim. Speak to a qualified clinician before changing what you take.