Origin & tradition
Not traditional as a supplement: melatonin's role as a sleep and circadian hormone was identified in the 1950s–60s.
Western tradition · Neurohormone
Beyond sleep: melatonin is a potent mitochondrial antioxidant whose production declines ~80% from youth to old age.
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Not traditional as a supplement: melatonin's role as a sleep and circadian hormone was identified in the 1950s–60s.
Key active: Melatonin (N-acetyl-5-methoxytryptamine — pineal neurohormone).
Melatonin acts as a direct free-radical scavenger, mitochondrial membrane stabilizer, and circadian anchor. Its decline with age (~80% reduction) is considered a driver of circadian disruption and mitochondrial aging. Clinical trials cover sleep quality, cancer adjuvant, cardiovascular risk, and cognitive aging.
Effect summary
| Health outcome | Effect | Magnitude | Grade |
|---|---|---|---|
| Sleep onset latency | Decreases | Strong | A |
| Jet lag recovery | Increases | Strong | A |
| Circadian rhythm phase shift | Increases | Strong | A |
| Antioxidant / mitochondrial protection | Increases | Moderate | B |
| Sleep quality (total) | Increases | Moderate | B |
Grade: A = robust RCTs · B = several RCTs / meta-analysis · C = limited or mixed RCTs · D = observational or early data
Dosage guidance
More is not better — 0.5mg is often as effective as 5–10mg for sleep onset, with fewer next-day effects. High doses suppress endogenous melatonin production. Use the lowest dose that works. Extended-release may help with sleep maintenance.
Informational only — not a prescription or personalised medical advice. Consult a qualified clinician before starting any supplement or medication.
Evidence summary
Extensive human RCTs on sleep; growing trial base for aging endpoints
Melatonin acts as a direct free-radical scavenger, mitochondrial membrane stabilizer, and circadian anchor. Its decline with age (~80% reduction) is considered a driver of circadian disruption and mitochondrial aging. Clinical trials cover sleep quality, cancer adjuvant, cardiovascular risk, and cognitive aging.
According to PubMed and ClinicalTrials.gov: trial counts from ClinicalTrials.gov, peer-reviewed literature from PubMed. Counts auto-refresh weekly; last checked 2026-06-12. They include trials across many endpoints, not only longevity.
Informational only — not medical advice, a treatment claim, or a substitute for a qualified clinician. Evidence strength varies; we show mixed and null results on purpose.
Evidence collections
Compare the evidence
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