Jet lag is a temporary sleep problem that can affect anyone who quickly travels across several time zones. It is a combination of fatigue and other symptoms caused by traveling abruptly across different time zones. When you travel across more than two time zones by plane, your bodys "internal clock" or circadian rhythm needs time to adjust to the new sleep and wake cycles at your destination. Jet lag occurs because your bodys internal clock is synced to your original time zone, and it hasnt changed to the time zone of where youve traveled. The more time zones crossed, the more likely you are to experience jet lag.

Jet lag symptoms usually occur within a day or two after arrival at the destination and can include daytime fatigue, an unwell feeling, trouble staying alert, stomach problems, mood changes, and insomnia. Symptoms can vary, and some people may not notice any problems adapting to a new time zone. Although symptoms are temporary, they can affect your comfort while on vacation or during a business trip.

There is no cure for jet lag, but its effects can be reduced with careful planning. Strategies include maximizing your exposure to daylight to "reset" your body clock and napping briefly during the day when sleepy. Medical experts generally agree that flying eastward may cause more severe jet lag symptoms than flying toward the west.