What is Jet Lag? Jet Lag is a very common temporary sleep disorder. Most people have experienced this disorder while traveling. It's not only for those flying long distances but for driving and any sort of travel that takes you from your usual time zone. What causes Jet Lag? Circadian Rhythms are the key to jet lag. Our exposure to sunlight helps to determine our sleeping patterns. Jet lag comes from your body's natural biological "clock" becoming thrown off from the time zone changes. Your body has a natural "clock"