How to get over jet lag faster

Key takeaways

• Jet lag is your body clock running on the wrong time zone. It usually shows up after crossing two or more time zones and fades as the clock catches up.

• Expect about an hour a day. The CDC puts the average adjustment at about 1.5 hours a day after flying west and 1 hour a day after flying east.

• Light is the strongest lever. After flying east, get morning light and avoid evening light; after flying west, do the reverse.

• Melatonin helps some travelers, if timed right. A low dose taken near bedtime at your destination can speed things up, especially on long eastward trips.

• For a trip of under two days, stay on home time. There isn’t enough time to adjust, and shifting back afterward costs you twice.

What jet lag is, and why east is worse

Your body runs on an internal clock that keeps sleep, alertness, hunger and hormone release on a roughly 24-hour cycle. Fly across several time zones and that clock keeps running on home time while the sun, your meals and your alarm switch to the new one. The mismatch is jet lag: poor sleep at night, sleepiness during the day, trouble concentrating, an upset stomach and a general feeling of being off.

The CDC’s guidance for travelers says jet lag needs a trip across at least two time zones, and it puts the average recovery at about 1.5 hours a day after westward travel and 1 hour a day after eastward travel. So a flight from New York to London, five hours ahead for most of the year, can take most of a week to fully settle.

Flying east is harder because the body clock naturally runs a little longer than 24 hours. Pushing it later, as you do after flying west, goes with its tendency. Pulling it earlier, as eastward travel demands, works against it.

Before you fly

If the trip is long enough to adjust to, you can start the shift at home. In the days before an eastward trip, go to bed and get up an hour earlier each day; before a westward trip, an hour later. Moving more than an hour a day isn’t worth it, because a bigger jump barely shifts the clock any faster and tends to leave your sleep out of step with it. Even two or three days of this takes a few hours off the adjustment you’ll face on arrival.

For a short trip of under about two days, it’s usually better not to adjust at all. Keep your sleep and meals as close to home time as you can, and plan important meetings for hours when you’d normally be alert.

On the plane

• Set your watch or phone to destination time when you board, and start thinking in that time zone.

• Sleep on the plane if it’s nighttime at your destination, and stay awake if it isn’t.

• Go easy on alcohol. It can help you nod off but makes sleep lighter and more broken.

• Drink water. It won’t reset your body clock, but dehydration can make the physical symptoms of jet lag worse.

After you land

Light is the main signal the body clock uses to set itself, so when you see it counts for more than almost anything else.

• After flying east, get bright light in the morning, ideally outdoors, and keep the evening dim. Dark sunglasses help if you have to be outside then.

• After flying west, avoid bright light early in the morning and get plenty in the late afternoon and evening.

One exception: after a very long eastward flight, around eight time zones or more, early morning light at the destination can land at the wrong point in your body’s cycle and push the clock the wrong way. A 2009 review of how to travel without jet lag describes this wrong-way shift as common on trips that long, so for the first few days, avoid bright light early in the morning and get it later in the morning instead.

Eat, sleep and plan your day on local time. If you’re struggling to stay awake, a nap of 20 to 30 minutes can help you get through the afternoon, but a long or late nap makes the first night’s sleep harder. Caffeine helps with daytime sleepiness too; stop it at least six hours before bed, since it keeps working long after the cup is empty.

Does melatonin help with jet lag?

For many people, yes. Melatonin is the hormone your body releases in the evening to signal that night has started, and a supplement taken at the right time can nudge your clock toward a new time zone.

A Cochrane review of 10 trials found that melatonin taken close to bedtime at the destination (10pm to midnight) reduced jet lag for travelers crossing five or more time zones, with the bigger benefit on eastward flights. Doses between 0.5 mg and 5 mg worked about equally well, and higher doses added nothing. The American Academy of Sleep Medicine’s guidance on circadian rhythm disorders gives melatonin its strongest level of recommendation for jet lag.

Timing decides whether it helps. Taken earlier in the day, melatonin can make you drowsy at the wrong time and slow the adjustment. A few other things to know:

• In the US, melatonin is sold as a dietary supplement and isn’t held to the standards of a medicine. A Canadian analysis of about 30 products found melatonin content ranging from 83% less to 478% more than the label said, and a 2023 US study found 22 of 25 melatonin gummies were inaccurately labeled.

• People who are pregnant or breastfeeding, have epilepsy, or take blood thinners such as warfarin should check with a doctor before using it.

• The NHS doesn’t recommend it for jet lag, citing a lack of evidence.

Prescription sleeping pills are sometimes used for short stretches after a long trip, but that’s a decision for a doctor.

When jet lag isn’t the problem

Jet lag should ease at roughly a day for each time zone crossed, so within a week or so for most trips. If you still can’t sleep or stay alert after that, it may be something else. Frequent travelers who struggle on every trip can get a tailored plan from a sleep specialist.

Frequently asked questions

How long does jet lag last?

On the CDC’s averages, about a day for each time zone after flying east and about two-thirds of a day per zone after flying west. Most trips settle within a few days to a week.

Should I stay awake all day after an overnight flight?

Try to stay up until a normal local bedtime, getting outdoor light during the day. If you can’t make it, a short nap of 20 to 30 minutes in the early afternoon is fine; set an alarm so it doesn’t turn into a long sleep.

Is jet lag worse flying east or west?

East, for most people. On the CDC’s averages, a trip across six time zones takes about four days to settle after flying west and about six after flying east.

When should I take melatonin for jet lag?

Close to your bedtime at the destination, usually between 10pm and midnight local time, starting the night you arrive and continuing for a few nights.

What’s the difference between jet lag and travel fatigue?

Travel fatigue comes from the trip itself: cramped seats, dry cabin air, a long day. It clears after a good night’s sleep. Jet lag comes from the time difference and lasts until your body clock catches up, which can take days.