Jet lag is a condition in which the body's circadian rhythm becomes disregulated, usually due to long-distance air travel.
The condition can last for up to a week, with the recovery rate taking one day per time zone crossed.
When a person crosses many time zones in a rapid manner, the body clock will become desynchronized due to a vast difference in the day and night patterns that it is used to. This upsets the balance between the body's different rhythms, such as for eating and sleeping, and if the body cannot readjust these rhythms quickly, the desychronization results in jet lag.
Symptoms of jet lag can be widely varied, depending on the individual and the number of time zones crossed. The most common problems are fatigue, headaches, inability to sleep, sleeping at the wrong times, feeling irritable or disoriented and mild depression. Some travelers may also experience diarrhea or constipation as symptoms of a disregulated body clock.
Recovery from jet lag can be as little as one day for some to nearly a week for others. The condition is not related to the length of a flight as much as the direction. Flying from east to west, such as across the United States, often results in jet lag.
Travelers can reduce or even eliminate the jet lag effect by trying to adapt to the new time zone before the trip. This can be accomplished by starting the day an hour earlier or later than the normal time, up to a week before departing. Light box therapy may also be of some use when trying to adjust the circadian rhythm.
While traveling, it is best to avoid caffeinated beverages and to drink water to maintain hydration. Some may find sleeping on the plane leads to a quicker adjustment upon arrival. Others may want to take a long trip in small hops, allowing for body clock adjustment along the way. After arrival, exposure to sunlight and properly timed meals can help with jet lag recovery.
Jet lag is a common condition that can be overcome with common sense and proper preparation.