Causes of jet lag


Jet lag is primarily caused due to advanced or delayed sleep time while crossing different time zones. It is a result of lack of sync between endogenous Circadian Clock and the sleep-wake hours of the destination time zone. The etiological factors behind jet lag are discussed below-

• Fluctuation and maladjustment in the levels of melatonin (hormone regulating sleep-wake cycles and other physiological functions within the body) that usually reaches peak level in blood at around 2 AM (according to local time zone)
• Crossing multiple time zones within a very short period of time
• Frequent exposure to change in time zones mainly due to occupational requirements
• Travel headed to east ( due to considerable shortening of the day length )
• Complete loss of sleep during the entire time of travel
• Exposure to bright light (illumination within aircraft or sunlight) during an inappropriate time of the Circadian Cycle (due to re-adjustment of the normal Circadian Rhythm)
• Lack of adaptability to Circadian Misalignment (mainly due to age)

• Lack of physical fitness to adjust to changes in sleep-wake cycles or extreme sensitivity to change in time zones
• Dehydration-induced by very high environmental temperature (of destination)
• Shortage of oxygen in the body due to reduced pressure at very high altitudes
• Lack of adjustment with cabin pressure and low humidity within the aircraft (causes dehydration)
• Deterioration of body’s resistance to fluctuations induced by external environment due to age or existing diseases