Does melatonin help with jet lag?
Yes, mostly after flights across 5 or more time zones, and more flying east than west. In a 2002 review, nine of ten trials found melatonin cut jet lag when taken close to bedtime at the destination, 10pm to midnight. Doses from 0.5 to 5 mg worked about the same, and more than 5 mg didn’t add anything.
It’s tempting to take melatonin on the plane, or at 3pm local time when the fog hits, and both are the wrong hour. The trials gave it at bedtime in the new time zone, and the same review warned that a dose early in the day can make you sleepy and slow down your adjustment.
We’d take 0.5 to 5 mg, starting low, at bedtime in the new time zone for the first 4 nights, and plan your daylight as closely as your dose. Light moves your body clock too, and the wrong light at the wrong hour can push it the wrong way.
Your body clock is like an old watch you can only wind forward or back an hour or so a day, with melatonin and light as your fingers on the crown.
How long it takes to adjust
Real travelers’ clocks move about 57 minutes a day after flying east and about 92 minutes a day after flying west, so going east is harder. That puts a 6 hour flight east at about 6 days to adjust on your own, and a 7 hour move west at about 5.
| Trip | Your clock has to move | Days to adjust on your own |
|---|---|---|
| New York to Paris | 6 hours earlier | About 6 |
| Los Angeles to Tokyo | 7 hours later | About 5 |
| New York to Los Angeles | 3 hours later | About 2 |
| Chicago to London | 6 hours earlier | About 6 |
One trip, worked through
New York to Paris in winter, sleeping 11pm to 7am at home. Your body temperature low, the point your light plan turns on, sits about 3 hours before you wake, so about 4am New York time, which is 10am in Paris.
On the day you land, wear dark sunglasses from 7 to 10am, then get outside from 10am to 1pm. Light before the low would push your clock the wrong way, and light after it pulls you toward Paris time. Take 0.5 to 5 mg at about 10:30pm, starting low, for the first 4 nights. Each day the light window moves about an hour earlier, and after about 6 days you’re on Paris time.
Flying west is gentler, and the trials found less benefit from melatonin that way. From Los Angeles to Tokyo, the plan is mostly evening light on the first days and a dark room after.
Before you fly
Charmane Eastman and Helen Burgess, sleep researchers at Rush University in Chicago, suggest starting before you fly. Before a trip east, that means going to bed and getting up about an hour earlier each day, with bright light soon after you wake, and they write that even one or two days of it helps reduce the jet lag after. The planner offers this as an optional start 3 days out.
When to skip it
- Under 5 time zones. The trials found benefit from 5 zones, so light alone is usually enough. Melatonin is optional.
- Trips of 3 nights or fewer. Stay on home time where you can. Melatonin works by moving your clock, and you want yours to stay put.
- Epilepsy or blood thinners such as warfarin. The review found case reports of possible harm. Ask your doctor first, as you should if you take any daily prescription.
Outside the US, melatonin is often prescription only, so check your own country’s rules. Don’t drive after a dose, which includes the rental car the morning after.
Put your cities, date and usual sleep into the planner below for a card a day: when to take it, when to wear dark glasses and when to get outside.
Plan your trip
Paris is 6 hours ahead of New York on that date. Your clock has to move 6 hours earlier, the hard way: about 6 days on its own.
Every day
3 days beforeMon, Dec 7
If you can, go to bed and get up an hour earlier than usual, with bright light soon after you wake. In the lab, a move of an hour a day like this shifted the clock without jet lag.
2 days beforeTue, Dec 8
- If you can, go to bed and get up 2 hours earlier than usual, with bright light soon after you wake.
1 day beforeWed, Dec 9
- If you can, go to bed and get up 3 hours earlier than usual, with bright light soon after you wake.
Pack dark sunglasses and an eye mask.
The day you landThu, Dec 10
Sleep on the plane if you can. It's night where you're going.- Dark sunglasses from 7am to 10am, and keep the room dim. Light now would push your clock the wrong way.
Get outside from 10am to 1pm. Daylight now moves your clock the way it needs to go.
0.5 to 5 mg at 11pm, bedtime here, starting low.- Sleep 11:30pm to 7am on the local clock.
Day 2Fri, Dec 11
- Dark sunglasses from 6am to 9am, and keep the room dim. Light now would push your clock the wrong way.
- Get outside from 9am to noon. Daylight now moves your clock the way it needs to go.
- 0.5 to 5 mg at 11pm, bedtime here, starting low.
- Sleep 11:30pm to 7am on the local clock.
Day 3Sat, Dec 12
- Keep the room dark, and wear dark sunglasses from when you wake until 8am.
- Get outside from 8am to 11am. Daylight now moves your clock the way it needs to go.
- 0.5 to 5 mg at 11pm, bedtime here, starting low.
- Sleep 11:30pm to 7am on the local clock.
Day 4Sun, Dec 13
- Keep the room dark, and wear dark sunglasses from when you wake until 7:15am.
- Get outside from 7:15am to 10:15am. Daylight now moves your clock the way it needs to go.
- 0.5 to 5 mg at 11pm, bedtime here, starting low.
- Sleep 11:30pm to 7am on the local clock.
Day 5Mon, Dec 14
- Keep the room dark until 6:15am. You'll be asleep for it.
- Get outside from 7am to 9:15am. Daylight now moves your clock the way it needs to go.
- Sleep 11:30pm to 7am on the local clock.
Day 6Tue, Dec 15
- Keep the room dark until 5:15am. You'll be asleep for it.
- Get outside from 7am to 8:15am. Daylight now moves your clock the way it needs to go.
- Sleep 11:30pm to 7am on the local clock.
Day 7Wed, Dec 16
- Keep the room dark until 4:15am. You'll be asleep for it.
- Get outside from 7am to 7:15am. Daylight now moves your clock the way it needs to go.
- Sleep 11:30pm to 7am on the local clock.
Day 8Thu, Dec 17
About adjusted. Keep your usual hours here, get outside in the morning and keep evenings dim.
Times are on the local clock. Your body temperature low is your home wake time minus 3 hours, and it moves about 57 minutes earlier a day after flying east, about 92 minutes later after flying west. The 3 hour light windows, the 4 nights of melatonin and the short-trip rule are ours.
4 sources
- Herxheimer A, Petrie KJ, Melatonin for the prevention and treatment of jet lag, Cochrane Database of Systematic Reviews, 2002pubmed.ncbi.nlm.nih.gov
- Eastman CI, Burgess HJ, How to travel the world without jet lag, Sleep Medicine Clinics, 2009pubmed.ncbi.nlm.nih.gov
- Khalsa SBS and others, A phase response curve to single bright light pulses in human subjects, Journal of Physiology, 2003pubmed.ncbi.nlm.nih.gov
- National Center for Complementary and Integrative Health, Melatonin: What You Need To Know, last updated May 2024nccih.nih.gov
