Jet lag

Jet lag occurs when your usual sleep routine is disrupted after a long flight, typically due to traveling across at least 2 time zones, especially in an easterly direction. It gets worse the more times zones you cross.

Why does jet lag happen?

• Your body uses sunlight to help tell the difference between day and night. A chemical in the brain called melatonin plays a big role in this.
• Body functions such as your temperature, heart rate, digestion, and sleep follow a daily cycle called the circadian rhythm, which is usually in a 24-hour period.
• When you travel to a new time zone, this natural cycle gets confused.
• Not getting enough sleep before or during your trip can make jet lag worse.
• There’s no quick fix for jet lag, but you can feel better with some good planning.

Jet lag is usually worse after flying east, for example, from Aotearoa New Zealand to the United States. This is because you 'lose time' and your body clock has to move forward. If jet lag really bothers you, it might help to choose a route that goes west instead of east, if you can.

It can take your body a few days to a few weeks to get used to a new time zone, usually about 1 day for each hour of time difference.

The main symptoms of jet lag are:

• tiredness, exhaustion, fatigue and low energy
• difficulty staying awake during the day, and problems sleeping at bedtime and waking up in the morning
• problems with concentration, focusing and remembering things.

Jet lag can also sometimes cause stomach problems, feeling sick, constipation, changes in appetite and mild anxiety.

It can take your body a few days to a few weeks to get used to a new time zone, usually about 1 day for each time zone, or hour of time difference.

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You can’t completely stop jet lag, but there are ways to make it less severe.

Before you travel

• You can start adjusting your body clock before you travel by slowly changing your bedtime and wake-up time. If you’re going east, try going to bed and waking up an hour earlier each day. If you’re going west, go to bed and wake up an hour later each day.
• When traveling across many time zones, think about breaking the trip with an overnight stop halfway.

During your travel

• Change your watch to the time at your destination as soon as your flight starts. If you can, try to sleep on the plane when it would be night time where you’re going. Using an eye mask and ear plugs can help.
• Drink plenty of water to stay hydrated, as dehydration can make jet lag worse. Avoid too much caffeine and alcohol during the flight.
• Move around by stretching or walking during long flights to help reduce tiredness and keep your blood flowing.

After you arrive

• Spend time outside during the day because natural sunlight helps your body adjust to the new time.
• Eat breakfast, lunch, and dinner at the local meal times, even if you don’t feel hungry.
• Avoid relying too much on caffeine from coffee or energy drinks to stay awake, as it can make adjusting your body clock harder.

Using medication for jet lag is usually not necessary. It’s not a good idea to take sleeping pills during your flight because you need to be alert in case of an emergency. Some travellers use alcohol to fall asleep, but this can actually disturb your normal sleep patterns and make jet lag last longer. Alcohol can also cause headaches and dehydration, making your jet lag symptoms worse.

Some people have found that melatonin, taken at the right time, may help them adjust more quickly to new time zones, particularly after eastward travel. Read more about melatonin for jet lag.