Jet lag

Overview

Melatonin has the strongest evidence for jet lag, with medium effect size, evidence, and trust across 11 studies. Taking melatonin while traveling may improve alertness and reduce daytime sleepiness after arrival, though it does not always speed falling asleep or improve sleep quality.

Lower doses around 0.5 mg appear as effective as higher doses, while doses above 5 mg may add little benefit but increase drowsiness. Benefits appear greatest when traveling eastward across five or more time zones. See the heatmap and evidence reviews below for full details.

Effect graph

Unlock now

Relevant supplements

Relevant supplements sorted by DEX Score.


Melatonin	★★★★★	Medium

Unlock now

Studies

Find individual evidence reviews for supplements sorted by DEX Score.

1 supplement for rated at least stars. All purchase bands. No minimum star filter.

MelatoninView supplement →

Consider purchase★★★★★

How we scored this

Effect SizeMediumEvidenceVery HighTrustMedium

Evidence Review

Taking melatonin while traveling can help with jet lag. A dose of 2–3 mg at bedtime for a few nights after arrival may improve alertness and reduce daytime sleepiness. It may also help with fatigue, though it does not always make falling asleep faster or improve sleep quality.
Lower doses as small as 0.5 mg work just as well as higher doses, and taking more than 5 mg doesn’t add benefit but may make you feel overly drowsy. The best results are seen when traveling eastward across five or more time zones. Starting melatonin before the trip does not help prevent jet lag, and for westward travel the benefit is less certain. Immediate-release types are generally more effective than slow-release types.

Browse 11 studies1 meta-analysis

RCTMelatonin treatment for eastward and westward travel preparation2010

In a jet-lag preparation trial, 3 mg regular-release, sustained-release, or surge-sustained melatonin advanced circadian phase for eastward and westward travel adaptation.

Effect: Benefit
Dose: 0.5 mg/day

View on PubMed

MetaEfficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis2006n=651

A meta-analysis of 17 RCTs (651 participants) found no evidence that exogenous melatonin improved sleep onset latency in secondary sleep disorders or sleep restriction conditions, though it appeared safe short-term.

Effect: No Benefit
Participants: 651

View on PubMed

Controlled trialMelatonin and zopiclone as facilitators of early circadian sleep in operational air transport crews2004

In 30 transport aircrew, melatonin 2 mg or zopiclone 5 mg facilitated early circadian sleep after transatlantic missions without impairing post-sleep psychomotor performance.

Effect: Benefit
Dose: 2 mg/day

View on PubMed

Systematic reviewMelatonin for the prevention and treatment of jet lag2002

A Cochrane systematic review concluded melatonin near destination bedtime can reduce jet lag after crossing five or more time zones, with larger eastward shifts benefiting most.

Effect: Benefit
Dose: 5 mg/day
Population: Adults

View on PubMed

RCTJet lag: clinical features, validation of a new syndrome-specific scale, and lack of response to melatonin in a randomized, double-blind trial1999

In 257 physicians after a 6-hour eastward return flight, none of four melatonin regimens (5 mg, 0.5 mg bedtime, or shifting 0.5 mg) clearly outperformed placebo on jet lag ratings.

Effect: No Benefit
Duration: 5 days
Dose: 5.0 mg/day

View on PubMed

Melatonin: aeromedical, toxicopharmacological, and analytical aspects1999

A review of melatonin aeromedical use concluded it modulates circadian rhythms and is widely self-administered for sleep disorders, though optimal dosing remains debated.

View on PubMed

RCTComparative study to determine the optimal melatonin dosage form for the alleviation of jet lag1998n=320

In 320 travelers after eastward flights, melatonin 5 mg fast-release reduced jet lag symptoms more than 0.5 mg fast-release, 2 mg controlled-release, or placebo over 4 days.

Effect: Benefit
Duration: 4 days
Dose: 5.0 mg/day
Participants: 320

View on PubMed

RCTA double-blind trial of melatonin as a treatment for jet lag in international cabin crew1993

In 52 international cabin crew, late-start melatonin 5 mg for 5 days showed a trend toward faster jet lag recovery versus early-start or placebo regimens.

Effect: Benefit
Duration: 5 days
Dose: 5 mg

View on PubMed

RCTMelatonin and jet lag: confirmatory result using a simplified protocol1992n=15

In 30 travelers on eastward flights, melatonin 8 mg on return day and for 3 days improved global efficacy, morning fatigue, and evening sleepiness versus placebo by day 8.

Effect: Benefit
Duration: 3 days
Dose: 8 mg/day
Participants: 15

View on PubMed

The effect of 6, 9 and 11 hour time shifts on circadian rhythms adaptation of sleep parameters and hormonal patterns following the intake of melatonin or placebo1991

In a controlled study of 6-, 9-, and 11-hour time shifts, melatonin improved circadian adaptation of sleep parameters and hormonal patterns versus placebo after transmeridian travel.

Effect: Benefit

No source link

RCTEffect of melatonin on jet lag after long haul flights1989n=20

In 20 volunteers after long-haul flights, melatonin 5 mg before, during, and after travel reduced jet lag symptoms versus placebo in a crossover trial.

Effect: Benefit
Duration: 3 days before flight, during flight, and 3 days after arrival
Dose: 5 mg/day
Population: ALL patients
Participants: 20
Ages: 28–68

View on PubMed

Unlock now

Evidence visualised

Same ratings as above, aggregated so you can see coverage and imbalance.

Purchase-guidance distribution

How many supplements fall in each purchase band

Effect-size distribution

How large the reported benefits tend to be

Study distribution across 1 supplements for jet lag (11 studies total).
Supplement	DEX	Studies	Meta-analyses	Share
Melatonin	★★★★★68%	11	1	100%

Unlock now

Overview

Effect graph

Relevant supplements

Studies

Evidence visualised

On this page