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evidence · mechanism · dose
Supplements/Compound

Melatonin

Pineal hormone that signals biological night — most effective for circadian-rhythm shifts.

Sleep & RecoveryHealthy Aging

Overview

An indoleamine hormone synthesized in the pineal gland from serotonin. Released in darkness; signals biological night to peripheral tissues.

Natural sources
  • Endogenous (pineal gland)
  • Small amounts in tart cherries, pistachios
Common forms
  • Immediate release
  • Extended release (better for sleep maintenance)

Mechanism of action

Acts on MT1 (sleep onset) and MT2 (circadian phase) receptors in the suprachiasmatic nucleus and peripheral tissues.

Pathways
  • · MT1/MT2 receptor signaling
  • · Circadian rhythm regulation
  • · Antioxidant (direct radical scavenging)
Receptors
  • · MT1, MT2 (G-protein coupled)

Effects on the body

Decreases
Sleep onset latency
Supports
Circadian rhythm re-alignment (jet lag, shift work)
Supports
Antioxidant defense

Organ system effects

Brain & CNS

Receptor agonism in SCN drives sleep onset and phase shifts.

Endocrine

Modest effects on cortisol rhythm and reproductive hormones (avoid high doses long-term).

Evidence-based benefits

Reduces sleep onset latency (~7 min average)

Moderate evidence

Highly effective for jet lag

Strong evidence

Useful for shift-work sleep disorder

Moderate evidence

Helpful for delayed sleep phase disorder

Moderate evidence

Potential side effects

Common
  • · Morning grogginess (especially at high doses)
  • · Vivid dreams
Rare
  • · Headache
  • · Dizziness
Serious
  • · Potential effects on reproductive hormones with chronic high-dose use

Drug interactions

Anticoagulants
May increase bleeding risk.
moderate
Immunosuppressants
Mild immunomodulator.
moderate
Sedatives
Additive CNS depression.
moderate
Anti-hypertensives
May modestly lower BP.
minor

Safety & non-supplemental interactions

Educational summary — always confirm with your clinician or pharmacist before starting, stopping, or combining with prescription therapy.

Avoid if you are
  • ·Pregnant or trying to conceive
  • ·Breastfeeding
Avoid with these conditions
  • ·Autoimmune disease
  • ·Seizure disorder
  • ·Depression
Avoid / monitor with these medications
  • ·Alcohol, benzodiazepines, opioids, sedating antihistamines (additive CNS depression)
  • ·Warfarin and anticoagulants
  • ·Immunosuppressants
  • ·Diabetes medications (glucose effects)
  • ·Hormonal contraceptives (raise melatonin levels)
  • ·Fluvoxamine (raises melatonin 17-fold)

Supplement interactions

Pairs well with
  • Magnesium glycinate
    Complementary mechanism for sleep quality.
  • L-theanine
    Promotes relaxation without sedation.
Avoid combining with
  • Alcohol
    Disrupts sleep architecture; defeats melatonin's purpose.

Dosing & bioavailability

Typical dose
0.3–1 mg (low-dose physiologic)
Beginner dose
0.3 mg
Study range
0.1–5 mg
Upper safe limit
Not formally defined; doses >3 mg often produce next-day grogginess
Best form
Immediate-release for onset; extended-release for maintenance
Timing
30–60 min before desired sleep time; for jet lag, time to destination dusk
With food?
Without food (faster onset)

Where to buy

Affiliate-style search links to reputable retailers. We don't endorse specific brands — verify third-party testing (USP, NSF, Informed Sport) before purchase.

Compound
Melatonin
Amazon
Wide selection · fast shipping
Compound
Melatonin
iHerb
Global delivery · curated brands
Compound
Melatonin
Thorne
Practitioner-grade · NSF tested

Scientific evidence (11)

Meta-analysisCochrane Database · 2002

Melatonin for the prevention and treatment of jet lag

Herxheimer A, Petrie KJ

Cochrane review of 10 RCTs of melatonin for jet lag across ≥5 time zones.

Key findings

Remarkably effective: 0.5–5 mg taken close to target bedtime; 0.5 mg as effective as 5 mg with fewer side effects.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — Reduces sleep onset latency

Live PubMed search

Live results for "Melatonin Reduces sleep onset latency" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "Reduces sleep onset latency". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — Highly effective for jet lag

Live PubMed search

Live results for "Melatonin Highly effective for jet lag" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "Highly effective for jet lag". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — Useful for shift-work sleep disorder

Live PubMed search

Live results for "Melatonin Useful for shift-work sleep disorder" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "Useful for shift-work sleep disorder". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — Helpful for delayed sleep phase disorder

Live PubMed search

Live results for "Melatonin Helpful for delayed sleep phase disorder" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "Helpful for delayed sleep phase disorder". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — randomized controlled trial

Live PubMed search

Live results for "Melatonin randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — meta-analysis

Live PubMed search

Live results for "Melatonin meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — pharmacokinetics

Live PubMed search

Live results for "Melatonin pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — safety adverse events

Live PubMed search

Live results for "Melatonin safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Melatonin — dose response

Live PubMed search

Live results for "Melatonin dose response" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Melatonin and "dose response". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewGoogle Scholar · 1970

Google Scholar: Melatonin — clinical evidence

Live Scholar search

Cross-database citation index for Melatonin as it relates to "clinical evidence".

Key findings

Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

Open study
Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.