What Is Jet Lag and What Causes It?
Scientifically, it's known as circadian dischronism, but most of us call it jet lag. Our bodies have an internal clock that determines when we are hungry, when we are sleepy, and when we are wide awake in a 24-hour period. It is the disruption of that internal clock that causes jet lag. Flying east or west for a few hours will put your body in a new time zone, but it can take awhile for the body's internal clock to adjust. This time of adjustment for your internal clock is what is known as jet lag. Some people adjust quickly to the change, and others take more time.
On average, it takes 1 day for every time zone crossed to get your internal clock to synchronize with the new time zone. You can take an active approach to speeding up this process by using some of the ideas in Prevention and Treatment.
Flying north or south, which doesn't involve changing time zones, is a bit easier on the body. However, the dry atmosphere, stale air, cramped posture, and lack of exercise while flying may add to the sense of being out of sync when you arrive at your destination. Generally, drinking some water, getting some fresh air, and exercising will take care of the problem.
