Jet Lag: Symptoms, Causes and How to Recover Faster

Jet lag is a sleep disorder caused by flying quickly across time zones, so your body clock is still set to home time while the clock on the wall says something else. It causes poor sleep, daytime sleepiness, trouble thinking clearly, a general unwell feeling and stomach upset (CDC). Your body clock shifts by only about 1 hour a day after flying east and about 1.5 hours a day after flying west, which is why eastward trips usually feel worse (CDC). This guide explains what jet lag is, its symptoms, why direction matters, how long recovery takes, and how to recover faster with light, sleep timing and melatonin.

It is educational, not medical advice.

Key Takeaways

• What it is: a mismatch between your internal clock and local time after crossing at least two time zones (CDC).
• Direction matters: for most people it is easier to push the clock later (flying west) than earlier (flying east) (CDC).
• Light is the main lever: after flying east, get bright morning light; after flying west, avoid bright early morning light (CDC).
• Melatonin research: in a review of 10 trials, 9 found melatonin taken close to the target bedtime at the destination reduced jet lag after flights across five or more time zones (Herxheimer and Petrie, 2002).

What Is Jet Lag?

Your body runs on a roughly 24-hour internal clock, the circadian rhythm, that times sleep, alertness and digestion. Light is the main signal that keeps it in step with local time (see our guide to the circadian rhythm). When you fly across time zones faster than the clock can adjust, it stays on home time for days. Jet lag is the result: a sleep disorder tied to travel across at least two time zones (CDC). How bad it gets depends on how many time zones you cross, the direction you fly and individual differences (CDC).

Jet Lag Symptoms: What Does Jet Lag Feel Like?

The CDC lists these symptoms (CDC):

• Trouble falling asleep or staying asleep at night
• Sleepiness during the day
• Difficulty concentrating and thinking clearly
• Feeling generally unwell
• Stomach and digestive upset

Because your clock is still on home time, after an eastward flight you may lie awake at the new bedtime and struggle to get up in the morning; after a westward flight you may get sleepy in the early evening and wake very early. Staying hydrated helps, because low fluid can make the physical symptoms worse (CDC).

Is Jet Lag Worse Going East or West?

East is usually harder. Most people find it easier to delay their clock than to advance it, and on average the body adjusts about 1.5 hours a day after westward travel but only about 1 hour a day after eastward travel (CDC). That is also why jet lag can feel worse coming home: if your return flight is the eastward leg, your clock has to move in the harder direction, often just as you go back to work.

The same light and timing steps work at home; our guide to how to fix your sleep schedule explains how to move your bedtime earlier without travel.

How Long Does It Take to Recover From Jet Lag?

A rough guide based on those average adjustment rates (CDC):

Time zones crossed	Flying east (about 1 hour a day)	Flying west (about 1.5 hours a day)
3	About 3 days	About 2 days
6	About 6 days	About 4 days
9	About 9 days	About 6 days

These are averages; individual differences mean some people adjust faster or slower (CDC). Online jet lag calculators work on the same idea, and the steps below can speed things up.

How to Recover From Jet Lag Faster

1. Shift your sleep before you leave

In the days before the trip, move your sleep about 1 hour later per day if you are flying west, or 1 hour earlier per day if you are flying east (CDC).

2. Time your light

Light is the strongest signal your clock receives. After flying east, get bright light in the early morning; after flying west, avoid bright light in the early morning. Once you arrive, get as much natural daylight at your destination as you can (CDC).

3. Keep naps short

Longer daytime naps can make it harder to sleep at night (CDC), so if you need one, keep it short. Our guide to non-sleep deep rest is an alternative when you are wiped out in the afternoon.

4. Watch caffeine and alcohol

Avoid caffeine in the hours before bed; the CDC's sample schedule stops caffeine after 4 p.m. Keep alcohol low, since it can help you fall asleep but makes sleep more broken (CDC).

5. Drink enough water

Low fluid can worsen the physical symptoms of jet lag, so drink water through the flight and on arrival (CDC). See our guide to electrolytes for the foods that help.

6. For short trips, stay on home time

For trips of less than about 2 days, the CDC suggests not trying to adapt at all and keeping your home sleep hours where you can (CDC).

If you need a nap after a flight, our guide to how long a nap should be explains how to keep it short so you can still sleep at night.

Melatonin for Jet Lag: What Research Shows

Melatonin is a hormone your brain releases in darkness and that light suppresses (CDC). Timed melatonin can shift the body clock: taken when your internal clock thinks it is early evening, it moves the clock earlier, which helps eastward travel, and taken when your clock thinks it is morning, it moves it later, which helps westward travel. Taking it at the wrong time can make the mismatch worse (CDC).

A Cochrane review of 10 trials found that 9 showed melatonin taken close to the target bedtime at the destination (10 p.m. to midnight) reduced jet lag after flights across five or more time zones; doses of 0.5 to 5 mg worked similarly, and doses above 5 mg were no more effective (Herxheimer and Petrie, 2002). The CDC notes that 0.5 to 1 mg is often enough to shift the clock and advises against high doses over 5 mg (CDC). The review authors also flagged that people with epilepsy and people taking warfarin should be careful with melatonin (Herxheimer and Petrie, 2002).

Our Melatonin Nasal Spray provides 200 mcg of melatonin with L-theanine per serving, for use as part of your bedtime routine; follow the label. Learn more on our melatonin ingredient page, in our melatonin dosage guide, in how long melatonin lasts and in melatonin side effects. Talk to a doctor before using melatonin if you take medication, are pregnant or breastfeeding, or have a health condition.

When to Talk to a Doctor

Jet lag should fade as your clock catches up. If sleep problems last well beyond the time your trip would explain, or you travel often and struggle every time, talk to a doctor. For more help with sleep at home, see how to fall asleep fast and our sleep health hub.

Frequently Asked Questions

What is jet lag?

A sleep disorder caused by rapid travel across at least two time zones, which leaves your body clock out of step with local time (CDC).

What are the symptoms of jet lag?

Poor sleep at night, daytime sleepiness, trouble concentrating, feeling generally unwell and stomach upset (CDC).

Is jet lag worse going east or west?

East, for most people. The body adjusts about 1 hour a day after flying east and about 1.5 hours a day after flying west (CDC).

How long does jet lag last?

Roughly one day per time zone after flying east, and a bit less after flying west, though people vary (CDC).

Why is jet lag worse coming home?

If your flight home is eastward, your clock has to move earlier, which is the harder direction for most people (CDC).

What is the fastest way to recover from jet lag?

Shift your sleep before you leave, time your light exposure, keep naps short, limit alcohol and caffeine near bedtime, and drink water (CDC).

Does melatonin help jet lag?

In a review of 10 trials, 9 found melatonin taken near the target bedtime at the destination reduced jet lag after flights across five or more time zones (Herxheimer and Petrie, 2002). Timing matters, and the CDC advises against doses over 5 mg (CDC).

Should I adjust to local time on a short trip?

For trips of less than about 2 days, the CDC suggests staying on your home sleep schedule where you can (CDC).

For a steady daily rhythm once you are home, see our science-based morning routine and how much deep sleep you need.

Sources

• Centers for Disease Control and Prevention. Jet Lag Disorder. CDC Yellow Book: Health Information for International Travel. CDC
• Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. 2002. PubMed 12076414
• Lewy AJ, et al. Light suppresses melatonin secretion in humans. Science. 1980. PubMed 7434030
• Burgess HJ, et al. Human phase response curves to three days of daily melatonin: 0.5 mg versus 3.0 mg. J Clin Endocrinol Metab. 2010. PubMed 20410229
• Ebrahim IO, et al. Alcohol and sleep I: effects on normal sleep. Alcohol Clin Exp Res. 2013. PubMed 23347102

These statements have not been evaluated by the Food and Drug Administration. This content is for education and is not medical advice. Our products are not intended to diagnose, treat, cure or prevent any disease. Talk with a healthcare provider before starting a new supplement if you are pregnant, breastfeeding or taking medication.