Introduction
You love your ranch in Montana but were long overdue for a vacation—this time to London. On travel day, the flight was smooth.
You imagined seeing the sights, visiting museums, and maybe even touring Buckingham Palace.
But your vacation hasn't started out so well. You can't
sleep, you're tired, and your stomach is giving you problems.
You
have jet lag.
Key points
- Jet
lag happens when you fly across one or more time zones. Most people need to
cross three time zones to notice jet lag. The more time zones you cross, the
worse jet lag may be.
- Jet lag can happen to anyone. Your age,
fitness, health, and how often you fly don't make a difference in whether you
get it.
- Jet lag usually is worse when a person flies east rather
than west. In other words, it will be worse when a person goes from the United
States to Europe than from Europe to the U.S.
- Jet lag makes you
feel bad, but it isn't serious. Most people get better 3 to 4 days after their
flight.
- The supplement melatonin may help relieve the symptoms of
jet lag. Sleeping pills may help too. But both of these also have downsides.
Jet lag may make it hard for you to fall
asleep, stay asleep, or stay awake during the day. Lack of sleep can make you
feel tired or tense and make it hard for you to focus. You may feel weak, or
you may lose your appetite. You may not be able to have a bowel movement
(constipation), or you may have diarrhea.
The symptoms of jet lag
take a few days to go away:1
- When you fly east, the number of days it takes
to recover from jet lag will be about two-thirds the number of time zones you
cross. For example, if you cross six time zones, it will take you about 4 days
to get back to normal.
- When you fly west, the number of days to
recover equals about half the number of time zones. So if you cross six time
zones, it will take you 3 days to recover.
Jet lag can happen to anyone. Your age, fitness, health,
and how often you fly don't make a difference in whether you get it.
Test Your Knowledge
Symptoms of jet lag include:
Continue to Why?
You
may get jet lag when you fly across one or more time zones. This happens when
you fly east to west or west to east. When you fly north to south or south to
north, you don't cross time zones, so you don't get jet lag.
Crossing time zones disrupts your body's "biological clock," or 24-hour
rhythms (circadian rhythms). You have symptoms because your
biological clock has not adjusted to the new time zone. Your body thinks that
you're still in your old time zone.
For example, if you fly from
Chicago to Rome, you cross seven time zones. This means that Rome is 7 hours
ahead of Chicago. When you land in Rome at 6:00 in the morning, your body
thinks it's still in Chicago at 11:00 the previous night. Your body wants to
sleep, but in Rome the day is just starting.
Other things besides
your wake/sleep cycle are affected. You may not be hungry at dinnertime in
Rome, but you may be very hungry in the middle of the day. Your bowel movements
may be on a different schedule than normal.
As your body adjusts
to the time change, the symptoms go away.
Test Your Knowledge
You can get jet lag when you:
- Take a long road trip.
This answer is incorrect.When you take a long road trip, you may cross
time zones. But the time it takes to cross them allows your body to adjust. You
get jet lag when you cross time zones quickly, as you do in an airplane. All the answers are correct.
- Fly across one or more time zones.
This answer is correct.You can get jet lag when you fly across time
zones. This happens when you fly east or west. All the answers are correct.
- Fly north or south.
This answer is incorrect.You can get jet lag when you fly east or west
across time zones. When you fly north or south, you don't cross time
zones. All the answers are correct.
Continue to How?
You can't cure jet
lag, but you may be able to reduce the symptoms using the hormone supplement
melatonin and sleeping pills. Other treatments besides medicines have not been
studied or have been studied very little, but they may be worth trying.
Melatonin and sleeping pills
Melatonin is a hormone that your body
makes. It regulates the cycle of sleeping and waking. Normally, melatonin
levels begin to rise in the mid- to late evening, remain high for most of the
night, and then go down early in the morning.
Taking melatonin
may help "reset" your biological clock. Studies show that it has reduced the
symptoms of jet lag for people flying both east and west.2
Suggestions about times and dosages vary among
researchers who have studied melatonin. Doctors recommend that you:
- Take melatonin after dark on the day you
travel and after dark for a few days after you arrive at your
destination.
- Take melatonin in the
evening for a few days before you fly if you will be flying east.
The safety and effectiveness of melatonin have not been
thoroughly tested. Taking large doses of it may cause sleep disruption and
daytime fatigue. If you have
epilepsy or are taking
blood thinners such as coumadin (Warfarin), talk to
your doctor before you use melatonin.
The sleeping pills eszopiclone (Lunesta) and zolpidem (Ambien) have been
studied for jet lag. They may help you sleep despite jet lag if you take them
before bedtime after you arrive at your destination.
You may have side effects of headaches, dizziness, confusion, and feeling sick
to your stomach.
Other things to do
None of the things in the
following lists have been proved to reduce jet lag, but some people find them
helpful.
Before you go, and on the plane
- Be well rested
before you start to travel.
- If you are flying east, go to bed 1
hour earlier each night for a few days before your trip. If you're flying west,
go to bed 1 hour later each night instead. But if your trip will last 2 days or
less, stay on your home time.
- Set your watch to your new time zone
as you start flying. If it's nighttime at your destination, try to sleep on the
plane. Sleep masks, earplugs, and headphones may help. If it's daytime at your
destination, try to stay awake.
- On the plane, drink water to avoid
dehydration. Avoid alcohol and drinks that contain caffeine.
When you arrive
- Try to change your schedule to the new time
as soon as you can. For example, if you arrive at 4 p.m., do your best to stay
awake until your usual bedtime. Get up in the morning instead of sleeping late.
- Think about light exposure. If you flew east, try to avoid bright
light in the morning, and get light in the afternoon. To avoid light in the
morning, stay indoors, such as by going to a museum. If you flew west, stay
awake during daylight, and try to sleep after dark. This may help adjust your
body clock and help your body make melatonin at the right time.
- Caffeine may help you stay alert during the day after you
arrive. But it also may make it harder to sleep at night.
If you have an important meeting or athletic event, try
to arrive a few days early so your body can adjust to the new time zone.
Test Your Knowledge
To cure jet lag, you can use melatonin before or after you
travel.
- True
This answer is incorrect.Nothing has been proved to prevent or cure jet
lag. Melatonin may help reduce symptoms.
- False
This answer is correct.Nothing has been proved to prevent or cure jet
lag. Melatonin may help reduce symptoms.
Continue to Where?
Now that you have read this
information, you may be able to reduce symptoms of jet lag. Talk to your doctor
about other things you might be able to do.
Return to topic:
References
Citations
- Waterhouse J, et al. (2007). Jet lag: Trends and
coping strategies. Lancet, 369(9567):
1117–1129.
- Herxheimer A (2008). Jet lag, search date June 2008. Online version of BMJ Clinical Evidence: http://www.clinicalevidence.com.
Credits
| By | Healthwise Staff |
|---|
| Primary Medical Reviewer | Anne C. Poinier, MD - Internal Medicine |
|---|
| Specialist Medical Reviewer | Lisa S. Weinstock, MD - Psychiatry |
|---|
| Last Revised | December 1, 2011 |
|---|
Last Revised:
December 1, 2011
Waterhouse J, et al. (2007). Jet lag: Trends and
coping strategies. Lancet, 369(9567):
1117–1129.
Herxheimer A (2008). Jet lag, search date June 2008. Online version of BMJ Clinical Evidence: http://www.clinicalevidence.com.