Melatonin: The Right Dose Is Much Lower Than Most Supplements Provide
Most melatonin supplements contain 5–10 mg, but research shows 0.5–1 mg is often equally effective with fewer next-day effects. This guide explains the evidence and how to use melatonin correctly.
Quick Answer
The effective dose of melatonin for sleep onset is 0.5–1 mg, not the 5–10 mg found in most over the counter products. Higher doses cause supraphysiological blood levels, can blunt the body's natural melatonin signal over time, and increase next day grogginess.
Key Takeaways
- 01---
- 02The body has melatonin receptors (MT1, MT2) that operate like a dimmer switch, not an on/off button. Receptor saturation occurs at much lower doses than most supplements provide.
- 03The clinical dosing guidelines in most European countries cap melatonin at 2 mg for sleep disorders, reflecting this evidence.
- 04| Use | Evidence Level |
- 05|---|---|
Quick Answer
The effective dose of melatonin for sleep onset is 0.5–1 mg, not the 5–10 mg found in most over-the-counter products. Higher doses cause supraphysiological blood levels, can blunt the body's natural melatonin signal over time, and increase next-day grogginess. Melatonin works best for circadian timing issues (jet lag, shift work) rather than treating insomnia disorders.
Why Dose Matters Disproportionately Here
Melatonin is a hormone produced by the pineal gland that signals darkness to the body. Normal peak endogenous levels are approximately 70–150 pg/mL. A 10 mg supplement produces blood levels 10–30× above the physiological peak.
The body has melatonin receptors (MT1, MT2) that operate like a dimmer switch, not an on/off button. Receptor saturation occurs at much lower doses than most supplements provide.
Evidence for Low-Dose Melatonin
A frequently cited 2001 study (Lewy et al., Chronobiology International) found 0.5 mg was as effective as 3 mg for phase-shifting circadian rhythms. A 2014 Cochrane-associated review concluded doses below 1 mg were effective for jet lag with a better side-effect profile than higher doses.
The clinical dosing guidelines in most European countries cap melatonin at 2 mg for sleep disorders, reflecting this evidence.
What Melatonin Is Good For
| Use | Evidence Level |
|---|---|
| Jet lag | Consistent — reduces adaptation time |
| Shift work circadian adjustment | Moderate |
| Delayed sleep phase disorder | Moderate |
| Sleep onset insomnia | Preliminary — modest effect |
| Chronic insomnia disorder | Insufficient — not recommended as first-line treatment |
Melatonin does not treat insomnia disorder (difficulty staying asleep, non-restorative sleep). For chronic insomnia, Cognitive Behavioural Therapy for Insomnia (CBT-I) has far stronger evidence.
Timing Is Critical
Melatonin's effect depends heavily on when you take it relative to your natural circadian phase:
- For sleep onset: 30–60 minutes before target sleep time.
- For jet lag (eastward travel): Take at destination bedtime, starting the day of travel.
- For jet lag (westward travel): Lower impact; melatonin is less effective for westward adjustment.
- For phase advance (early sleep): Take in the evening, 5–6 hours before natural sleep time.
Taking melatonin at the wrong phase can worsen circadian misalignment.
Dosage Reference
| Use | Dose | Timing |
|---|---|---|
| Jet lag / shift work | 0.5–1 mg | At destination bedtime |
| Sleep onset | 0.5–1 mg | 30–60 min before bed |
| Children (short-term, under medical advice) | 0.5–1 mg | 30 min before bed |
| Maximum studied dose | 5 mg | Limited added benefit over 1 mg |
Safety Notes
- Melatonin is generally regarded as safe for short-term use.
- Long-term use effects on endogenous melatonin production are not fully characterised — most guidelines recommend using it intermittently rather than nightly indefinitely.
- Children: Short-term use under medical advice appears safe. Long-term effects on pubertal timing are theoretically possible but unstudied adequately.
- Pregnancy: Limited safety data; avoid unless under medical supervision.
- Drug interactions: Additive effects with sedatives. May affect warfarin — check interactions.
Practical Next Steps
- Start with 0.5 mg — most pharmacies carry this dose or it can be achieved by cutting a 1 mg tablet.
- Take 30–60 minutes before your target bedtime.
- Use for jet lag or circadian adjustment, not nightly as a sleep aid.
- For persistent insomnia, pursue CBT-I before relying on melatonin.
FAQ
Frequently Asked Questions
Medically reviewed
Last reviewed May 9, 2026 by Migaku Editorial Team