Jet lag is a temporary sleep disorder that is caused when someone travels across two or more time zones rapidly. The main reason behind its occurrence is that it throws our normal functions out of sync. While a person is travelling across a number of time zones the body clock experiences changes to what its accustomed to, like routine changes in daylight and darkness resulting in disturbances in eating, sleeping, hormone variation and routine body temperature variation.
Adjusting to the jet lag is also dependant on the individual and other circumstances. For example, jet lag is more severe when we travel eastward. While travelling eastward it, it takes approximately one day per time zone to recover from jetlag whereas it takes half the time in the opposite direction. It’s also more severe in older people