With the summer come plans for travel, including flying long distances. For many travelers, that means jet lag. People who cross several time zones usually find that ambient light and other environmental cues can make their internal clocks go haywire. They have trouble sleeping, and when they do get sleep, it's shallow and fitful. Other jet lag symptoms include fatigue, irritability, nausea, trouble concentrating, headache, and upset stomach.
In general, it takes a day to adjust for every time zone you've crossed, although the older you are, the longer the adjustment will probably take. Eastward travel, which shortens your arrival day, is more troublesome than flights west, which provide extra hours to catch up in the new time zone. On trips that involve crossing only one or two time zones, you may be able to wake up, eat, and sleep on home time.
There's no sure way to avoid jet lag entirely, but you may be able to reduce its effects and duration. Here's how:
Start to shift before the trip. Gradually move mealtimes and bedtime closer to the schedule of your destination. For example, before traveling from the East Coast to Europe, go to bed a half-hour earlier than usual for several nights. If you'll be traveling a few time zones westward, stay up a half-hour later on several consecutive nights.
Keep well hydrated. Mild dehydration is common when traveling by air — and being dehydrated worsens the physical symptoms of jet lag. So drink plenty of fluids before, during, and after your flight. But avoid caffeine and alcohol. Both promote dehydration, and while you might think that coffee could help keep you awake — and alcohol, help you sleep — in fact, both can disturb your sleep.
Switch as rapidly as possible. If you'll be staying more than a day or two, adjust your sleeping and eating schedule to the new time zone as soon as you arrive (adjust your wristwatch on the plane). It can be difficult, but try to stay awake until the local bedtime, to rise in the morning when the locals do, and to get outside in the natural light. Take short naps if you need them. Engaging in social activities can also help your body clock adjust. If you usually exercise, keep it up while you're away.
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.