Jet lag happens when your body’s natural clock, or circadian rhythm, is disrupted by traveling to different time zone. This temporary sleep condition affects your energy and state of alertness.

Your body is aligned on a 24-hour cycle or body clock.

Your body follows this internal clock to perform specific biological functions, like releasing hormones that help you sleep, or increasing your body temperature to help you wake up at the start of your day.

Jet lag, also called desynchronosis or circadian dysrhythmia, is temporary, but it can interfere with your day in many ways. It can cause:

  • tiredness
  • drowsiness
  • lethargy
  • upset stomach

These symptoms aren’t dangerous, but they can affect your well-being. Preparing for jet lag, and possibly preventing it, can help you ensure this common disorder doesn’t disrupt your next trip.

Your body is naturally set to a 24-hour cycle that’s known as your circadian rhythm. Your body’s temperature, hormones, and other biological functions rise and fall according to this internal time gauge.

Jet lag disrupts your body’s clock for several reasons:

Your clocks don’t align

When you travel, your body clock may no longer align with the time in your new location.

For example, you may fly out of Atlanta at 6 p.m. local time and arrive in London at 7 a.m. local time. Your body, however, thinks it’s 1 a.m.

Now, just as you’re possibly reaching peak fatigue, you need to stay awake another 12 to 14 hours to help your body adjust to the new time zone.

Sleep timing

You could help prepare your body to the new time zone by sleeping on the plane, but several factors make it difficult to sleep while traveling. These include temperature, noise, and comfort level.

On the other hand, you might sleep too much on the plane and also throw off your body clock. This can happen because the barometric pressure on planes tends to be lower than air on the ground.

This is similar to being on a mountain that’s 8,000 feet (2.44 km) above sea level. While there’s just as much oxygen in the air, the lower pressure may result in less oxygen reaching the bloodstream. Lower oxygen levels may make you lethargic, which can encourage sleep.


Too much sunlight in the plane’s cabin or getting too much screen time while traveling can also affect your body clock. This is because light helps control how much melatonin your body makes.

The hormone melatonin helps your body get ready to fall asleep. It’s released in the brain at night when lights are dimmer.

During the day or when it’s bright, your body slows down melatonin production, which helps you be more awake.

Travel fatigue

Medical studies show that travel fatigue also contributes to jet lag. Changes in cabin pressure and high altitudes during air travel may contribute to some symptoms of jet lag, regardless of travel across time zones.

Some people may get altitude sickness when traveling on a plane. This can cause symptoms that may worsen jet lag like:

  • headache pain
  • fatigue
  • nausea that may worsen jet lag


Dehydration may also contribute to some symptoms of jet lag.

If you don’t drink enough water during your flight, you can get slightly dehydrated. In addition, humidity levels are low in planes, which can cause more water loss.

Coffee and alcohol

Travelers tend to enjoy beverages on a plane that they may not normally drink in those amounts or at those times.

Drinking coffee, tea, and other caffeinated beverages may prevent you from getting enough sleep on the flight. Caffeine can also make you more dehydrated.

Drinking alcohol might make you drowsy, but it can worsen the quality of sleep. Alcohol may also cause fatigue, headache pain, nausea, and other side effects that worsen jet lag.

Other factors that impact jet lag

Flying allows you to cross multiple time zones very quickly. It’s a very efficient way to travel. The more time zones you cross, the more severe your symptoms of jet lag may be.

Older travelers are more likely to experience more severe symptoms of jet lag than younger travelers. Young travelers, including children, may have fewer symptoms and adjust to the new time more quickly.

The direction you’re flying can have a big effect on your jet lag symptoms, too.

Symptoms tend to be more severe when traveling eastward. That’s because staying awake later to help your body adjust to a new time zone is easier than forcing your body to go to sleep earlier.

Jet lag occurs when your body’s natural rhythms are significantly upset by travel. When you fight your body’s natural rhythm to match the new time zone, you may begin experiencing symptoms of jet lag.

These symptoms usually show up within 12 hours of arriving at your new location, and they may last several days.

The most common symptoms of jet lag include:

  • tiredness and fatigue
  • drowsiness
  • irritability
  • feeling slightly disoriented and confused
  • lethargy
  • minor gastrointestinal issues, including upset stomach and diarrhea
  • excessive sleepiness
  • insomnia

For most people, symptoms of jet lag are mild. If you’re experiencing more severe symptoms, like cold sweating, vomiting, and a fever, you may be experiencing something else, such as:

If these symptoms last more than 24 hours, see a doctor for treatment.

You can help prevent or reduce jet lag by following these tips and strategies:

1. Snooze on the plane

Try to sleep on the plane if you’re traveling eastward and into a new day. Bring earplugs and eye masks to help reduce noise and light.

2. If you’re arriving at your destination while its nighttime there, try to stay awake for a few hours before you land.

This is when it’s a good idea to use screen time and light to help rewire your sleep schedule. Go to bed when you arrive and wake up in the morning to get acclimated to the new time zone.

3. Select flight times strategically

Pick a flight that allows you to arrive in the early evening. This way, staying up until it’s time for bed in your new time zone isn’t as hard.

4. Power nap

If bedtime is too far out and you need a nap, take a power nap of no more than 20 to 30 minutes. Sleeping longer than that may prevent sleep later in the night.

5. Plan extra days

Take a cue from athletes and arrive to your destination a few days early so you can get used to the time zone before any big event or meeting you plan to attend.

6. Anticipate the change

If you’re flying eastward, try getting up several hours earlier for a few days prior to your departure. If you’re flying westward, do the opposite. Stay awake later and wake up later to help you adjust before you even take off.

7. Don’t hit the booze

Avoid alcohol and caffeine the day before and the day of your flight. These drinks can interfere with your natural clock and prevent sleep. They may ultimately make the symptoms of jet lag worse.

8. Jet lag diet

Avoid salty and sugary foods while traveling. Stay hydrated with more fresh fruit and vegetables.

Also avoid overeating. A balanced diet can help reduce some jet lag symptoms like poor sleep, fatigue, bloating, and an upset stomach.

9. Get some exercise

It can be difficult to avoid sitting while on a flight, but a little exercise can help you sleep better. Try to stretch your legs whenever you can. Stand up only when it’s safe to do so.

If you’re changing flights, take a stroll around the airport or stand instead of sitting at your departure gate.

10. Drink herbal tea

Choose non-caffeinated herbal teas instead of coffee or tea. Research shows that drinking chamomile tea before bed can help improve how fast you fall asleep and your quality of sleep.

Jet lag doesn’t always require treatment, but a few options are available if the symptoms are bothersome and prevent you from performing your daily tasks.


The sun’s light tells your body it’s time to be awake. If you can, get outside in the sunlight during prime daylight hours once you get to your location. This can help reset your body clock and reduce symptoms of jet lag.

Light therapy

Lighted boxes, lamps, and visors can help reset your circadian rhythms. The artificial light simulates the sun and helps cue your body to be awake.

Once you arrive to your new destination, you may use this treatment to help you stay awake during periods of drowsiness so your body can better adjust.


Melatonin is a hormone your body naturally produces in the hours before bedtime. You can take over-the-counter (OTC) melatonin supplements to trigger sleep when your body is fighting it.

Melatonin is fast-acting, so take it no more than 30 minutes before you’re able to sleep.

Make sure you can also sleep a full 8 hours when you take it. Melatonin may make you drowsy if you wake up before the effects have worn off.

Sleeping tablets

If you experience insomnia when you travel, or if you have difficulty sleeping in new places, talk with your doctor about sleeping pills.

Some of these medications are available as OTC products, but your doctor can prescribe stronger versions if necessary.

Sleep medication has several side effects, so be sure to talk with your doctor and understand what they are before you take anything.

Eat at standard mealtimes

One study found that altering when you eat can help your body adjust to jet lag. Your body may signal hunger at times close to when you would typically eat. If you can, ignore those hunger cues.

Eat at the appropriate time for your new time zone to help your body follow the new cues. The foods you eat can also affect your quality of sleep once you do go to bed.

Take a hot bath

Take a relaxing hot bath or shower before you go to bed. This can help your body wind down and fall asleep faster.

Other home remedies

A good night’s sleep is a treatment that cures a lot of ills. Here are some tips to follow before you travel:

  • Rest well before you travel and don’t start your journey sleep deprived.
  • Have a light dinner a few hours before you plan to go to bed.
  • Avoid computer, TV, and phone screens for a few hours before you sleep.
  • Dim the lights a few hours before bedtime.
  • Drink chamomile tea or try relaxing essential oils like lavender to promote sleep.
  • Get a full night of sleep on your first night at the new location.
  • Reduce distractions by turning off phones and silencing electronics.
  • Use ear buds, noise machines, and eye masks to eliminate noise and light.
  • Adjust your schedule accordingly.

It may take several days for your body to adjust to the new time zone. Adjusting your eating, working, and sleeping schedules right away can help speed up the process.

While you adjust, you may experience symptoms of jet lag. Jet lag will likely end in a few days after you arrive.

Give yourself time to adjust to the new schedule, and you’ll still be able to enjoy your trip.