SupplementsAntioxidantsSleepCircadian
Melatonin is the hormone your brain releases as darkness falls to signal “night”. It’s sold as a sleep aid, and it’s also a potent antioxidant — but its real strength is timing, not sedation.
Key takeaways
- Melatonin is a circadian (body-clock) signal, not a sedative — timing matters more than dose.
- Strongest evidence: jet lag (crossing 5+ time zones) and circadian sleep disorders.1
- It modestly speeds sleep onset; it’s also a mitochondrial antioxidant.
- Use a low dose (0.5–3 mg) at the right time; more isn’t better and mistimed doses backfire.1
What it is
A hormone made by the pineal gland in response to darkness, setting the body clock. As a supplement it nudges the clock and, secondarily, acts as a direct and indirect antioxidant.
The evidence
A Cochrane review found melatonin, taken near the destination bedtime, reduces jet lag after eastward or long flights.1 It helps delayed sleep phase and shift-work timing, and modestly shortens time to fall asleep in insomnia. Its antioxidant role is real biologically but not the reason most people take it.
Dose & timing
0.5–3 mg about 30–60 minutes before the target bedtime. Doses above 5 mg aren’t more effective and can leave melatonin around at the wrong time. Timing is everything.
Safety & who benefits
Safe for short-term use; can cause grogginess or vivid dreams. Avoid before driving. Most useful for jet lag, shift work and delayed sleep phase; discuss long-term or paediatric use with a clinician.
References
Adult research summary for education, not a prescription.
- Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. www.cochrane.org
This article summarises nutrition science for education. It is not a substitute for individual medical advice; consult a professional before starting a supplement, in pregnancy, or alongside medication.