Jet Lag

Understand jet lag, and its causes and symptoms.

Jet Lag


What is jet lag?

Jet lag, also known as flight fatigue is when your normal sleep pattern is disturbed or your internal body clock (circadian rhythm) is out of sync after a long flight that crosses multiple time zones, usually leading to difficulties in falling asleep or staying awake at the right times.


Jet lag is primarily caused by the abrupt time zone changes during long-haul flights which affects your exposure to light and disrupts the normal release of melatonin (the hormone that plays a crucial role in regulating the sleep-wake cycle), and thus your body clock. Jet lag usually improves within a few days as your body adjusts to the new time zone.


Your jet lag symptoms can vary depending on the number of time zones you’ve crossed, the direction of travel (eastward or westward) and your overall health. The main symptoms of jet lag to look out for are:

  • Difficulty falling asleep or staying asleep at night
  • Trouble waking up in the morning
  • Sleepiness during the day
  • Tiredness and exhaustion
  • Gastrointestinal issues, such as indigestion, constipation, or diarrhoea
  • Concentration and memory problems

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