Melatonin
Also known as: N-acetyl-5-methoxytryptamine, sleep hormone, MLT
Melatonin is the hormone the pineal gland releases in darkness to signal night to the body clock. As a supplement it is used for sleep onset, jet lag, and shift-work adjustment. A meta-analysis of 19 RCTs found it shortens time to fall asleep and modestly increases total sleep time. Dose-response work shows 0.3 mg restores nighttime levels in older adults, and lower doses are often as effective as higher ones with less next-day grogginess. It is among the most popular sleep ingredients and works well in gummies.
Research summary
Agonist at MT1 and MT2 receptors in the suprachiasmatic nucleus, advancing circadian phase and lowering core temperature.
Dosage
Daily amounts, of compound.
| Lowest studied | Typical range | Highest studied | Upper limit |
|---|---|---|---|
| 0.3 mg | 0.5–3 mg | 10 mg | — |
0.5–3 mg taken 30–60 minutes before bed. Lower doses are often as effective as higher ones; 0.3 mg raised plasma melatonin to normal nighttime levels in older adults. Doses up to 10 mg appear in clinical studies but add little for sleep onset and increase morning grogginess. Not for children without professional guidance; avoid in pregnancy.
Standardization: ≥99% melatonin (USP)
Source material: synthetic
Format suitability
- Capsule
- Powder
- Tablet
- Softgel
- Gummy
- Liquid
Tiny dose that blends easily; gummies, orally disintegrating tablets, sprays, and liquids are all common. Light-sensitive; protect from UV.
Formulation notes
Additive drowsiness with other sedatives; may interact with anticoagulants, immunosuppressants, and blood-pressure medication. Prescription-only in the EU, UK, and Australia.
- Not for pregnancy
- Restricted in some countries
Sources
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