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What is jet lag and how can we help reduce it?

Jet lag is a short-term sleep problem, when your normal sleep is disturbed after a long flight – especially when crossing several time zones. Altered circadian rhythms – meaning your body clock going out of sync – are thought to be the main cause.

Symptoms can include extreme tiredness, difficulty sleeping and waking up, indigestion and problems with concentration and memory.1

There is no known cure for jet lag but there are things you can do to help reduce its effects.

Bask in the sunlight

Light is one of the main things controlling your body clock. So, going outside and getting a good dose of sunlight during the day can help your body adapt to the new time zone faster.2 If you plan to be in direct sunlight, be sure to protect your skin from burning with suitable clothing and sunscreen.

At bedtime, you should limit artificial light and block out any outside light to make the room dark enough for you to sleep.

Change your sleep routine

You should start to plan and slowly change your sleep routine before your trip. You could go to bed or wake up one hour earlier (or later) – nearer the time in your future destination.

Keep hydrated

The dry air inside plane cabins can lead to dehydration, which can increase the effects of jet lag, so drink plenty of water during your flight.

Avoid caffeine and alcohol

Drinking plenty of water does not mean all kinds of beverages! It’s not known if caffeine and alcohol affect your body clock but they will dehydrate you, so should be avoided.1,3

Time your meals

Meals are not as important as light, but can help the shift in your body clock. Like with your sleep routine, think about moving your meals by one hour before or after your usual eating time before your trip.


Exercise increases your natural body chemicals called endorphins, which can improve your mood and make you more alert. It is also important to stretch your legs on a plane to ensure good blood flow and help avoid blood clots.



Date of preparation: April 2019




1. NHS Jet lag.

2. Choy M, Salbu R. Jet Lag: Current and Potential Therapies. PT 2011; 36(4): 221–224.

3. Herxheimer A, Waterhouse J. The prevention and treatment of jet lag: It's been ignored, but much can be done. BMJ 2003; 326(7384): 296–297.

All accessed April 2019.