What is jet lag?

Jet lag is a sleep disorder which occurs when you cross multiple time zones (generally two or more) within a short period of time. It may result in sleep paralysis (a state between sleep and wakefulness where the brain is unable to distinguish between reality and dream) or short-term insomnia.

Generally, jet lag is faced by long-haul pilots.


The problem lies in the circadian rhythm. It is a biorhythm which repeats roughly every 24 hours, encompassing changes in body temperature, blood pressure, and other functions dependent on the time and the amount of light. When crossing multiple time zones rapidly, the circadian rhythm becomes disrupted. This results in disrupting the established bodily processes, giving rise to the following symptoms:

  • fatigue
  • disorientation
  • nausea
  • headache
  • insomnia
  • dehydration and lack of appetite
  • irritability
  • irrational behaviour

Jet lag symptoms are milder when travelling westwards, because when flying in this direction the day “only” becomes longer and the acclimatisation therefore takes less time. Generally, when travelling eastwards the symptoms tend to be more severe.

Treatment and how to overcome jet lag?

It may take several days for the body to recover from jet lag, depending on the period of time spent flying and also on other factors. However, there are some tips in order to adjust faster. It is important to avoid caffeine and alcohol before going to sleep, to regularly spend time outdoors in the daylight, and to avoid sleeping during the day. Cutting down on heavy meals after arrival and on long exercise before sleep also helps.

When it comes to pilots who are usually away from their base only for a few days, one of the ways often recommended to overcome jet lag is not to try and adjust to the new time zone, but to keep the daily routine of the home base instead. The body therefore does not have to adjust several times in a row within a short period of time.