Melatonin’s Main Role Is Circadian Timing
Key takeaway
Melatonin mainly tells the body it is night and helps time circadian rhythms; antioxidant and other roles are secondary research areas, not proven fertility or Alzheimer’s treatments.
- Melatonin marks biological night and supports circadian timing.
- Timing light and (when used) low-dose supplements target this pathway.
| Role | Evidence status | Consumer framing | ||
|---|---|---|---|---|
| Circadian night signal | Established | Primary sleep-fact claim | ||
| Antioxidant (lab/clinical) | Mixed / limited | Secondary, hedged | ||
| Fertility / Alzheimer’s disease-modifying | Speculative / preliminary | Do not headline |