Jet lag is the mismatch between your body’s internal clock and the local time at your destination. It usually appears when you fly across three or more time zones, and it usually passes by itself once the body adjusts. With a little preparation and the right habits, you can make it milder.
What jet lag is
Your body follows an internal clock of about 24 hours, the circadian rhythm. Under normal conditions it lines up with daylight: it keeps you alert while it is light and prepares you for sleep when it gets dark.
When you travel quickly to another time zone, the sun rises and sets at different hours from the ones your body expects. The clock needs days to adjust, and during that time sleep and wakefulness do not go as they should.
What the symptoms are
- Difficulty falling asleep, or sleep that is interrupted.
- Sleepiness and tiredness during the day.
- Difficulty with concentration and memory.
- Stomach discomfort, nausea or constipation.
- Changes in mood.
They may start immediately or a few days after arrival. Many people sleep well on the first night and struggle on the following ones.
How long it lasts
It is usually a temporary problem and fades when the internal clock syncs with local time. For people who often fly long distances, such as pilots, flight attendants and business travellers, the mismatch can keep recurring and spoil sleep for longer. If your sleep does not settle after a long time, talk to a doctor.
Before you travel
Make sure you have rested in the last nights before you leave, so you do not start the trip sleep deprived. Plan the first days at your destination, with time for sleep and for daylight, and do not leave things to the last minute. Rushing and stress make the trip harder.
On trips of several days, some people shift their bedtime gradually a few days before leaving, to get closer to the time at the destination. It may help, but it is not always possible with your work and obligations.
During the flight
Drink water, because it is easy to get dehydrated on a plane. Cut down on alcohol and caffeine or avoid them, and choose light food instead of heavy, fatty snacks. Get up and walk or stretch a little whenever you can.
After you arrive
Light is the strongest factor that sets the internal clock. Get out into daylight, with a walk or light exercise, and try to sleep at the hours the place you are in sleeps. If you do not have natural light, there are also light therapy lamps.
Watch alcohol, caffeine and heavy meals, and if you need a nap, keep it short, under 30 minutes, so it does not spoil your sleep at night.
If the trip is very short
On a trip of one or two days it is not always worth adjusting to the time at the destination. It may be easier to keep, as far as possible, the sleeping and eating hours you have at home, so you do not have to reset them when you return. For longer trips, the advice you read above applies, and it helps to be patient with yourself for the first few days.
Melatonin
Melatonin is a hormone the body produces, usually in the evening, and it helps you feel sleepy. With jet lag it may not be produced at the time you need it. There are supplements and medicines with melatonin, and some studies show they may help. Before you take anything for sleep, talk to a doctor, ideally before the trip.
A good bed is waiting for you
When you come back, the easiest way to find your rhythm again is in a bed that rests you. If you are thinking of changing your mattress, Sleep Match asks how you sleep and what you like and suggests mattresses.
In short
Jet lag passes, and with light at the right time, water, short naps and patience it passes more easily. Browse the mattresses to have sleep waiting for you at home.
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