sleep

Beating jet lag: how not to be a zombie on vacation

You finally saved up enough for that dream vacation. You envisioned delicious food, great sightseeing, and perhaps even a little romance. But wait.  You can’t sleep at night, can’t concentrate when you’re awake, and have a headache that just won’t go away.

You’ve got jet lag, the inevitable compilation of travel across time zones. But how can you beat it? And next time, can you plan ahead so it doesn’t happen at all?

How do our brains tell time?

We all have a built-in clock located in a part of our brain (called the hypothalamus) that governs our sleep-wake cycle (also known as our circadian rhythm). Our natural circadian rhythm is just a little longer than twenty-four hours, but other natural markers of time – known as “zeitgebers” (German for “time-givers”) – help keep us on a twenty-four hour schedule. The most powerful zeitgeber is sunlight. Others include physical activity and outside temperature.

As soon as your eyes tell your brain it’s getting dark outside, your brain prompts the release of melatonin and the lowering of your body temperature, making you tired and ready to hit the hay. At daybreak, a lack of melatonin and increase in your body temperature triggers your ‘rise and shine’ alertness. Your pets have this same built-in circadian rhythm – which is why they annoyingly wake you up at the exact same time each morning.

What exactly is jet lag?

When you travel quickly between different time zones, the new light-dark cycle confuses your internal clock, which can take days to adjust. As a result, you experience jet lag. The major symptoms include:

  • Insomnia (difficulty falling and staying asleep)
  • Daytime sleepiness
  • Difficulty concentrating
  • Constipation and decreased appetite.
  • Lousy or worsening mood

When should you expect to feel better? After about one day pertime zone traveled. For those traveling five or more time zones, you may start to feel better only upon boarding the return flight home, only to have your jetlag symptoms begin again at home.

But what if you didn’t travel across time zones but instead travelled north-south, and you’re still having symptoms such as headache, fatigue and difficulty concentrating? This is called travel fatigue and results from changes in your normal routine (like missing a night’s sleep, not staying hydrated, or eating at different times).  It should resolve after a good night’s sleep and getting back to your regular schedule.

What can you do to avoid jet lag?

The exact strategies depend on the direction of travel.

If you’ll be traveling west to east:

  • Starting three days before leaving, wake up an hour earlier each day and either go outside (if light out) or expose yourself to bright light for an hour.
  • After arriving at your destination, avoid bright light (including from phones and tablets) first thing in the morning.
  • Starting the first night at your new destination, take melatonin (1 to 3 mg of immediate release melatonin should suffice) about 30 minutes before you plan to get in bed. Continue for five nights.

If you’ll be traveling east to west:

  • Starting three days before leaving, go to sleep and wake up an hour later each day. Before your trip, try avoiding early morning light.
  • After arriving at your destination, expose yourself to lots of bright light first thing in the morning.

Melatonin may not be safe if you take the blood thinner warfarin, take certain medications for seizures, of are pregnant or breastfeeding. Speak to your doctor first. Typical side effects include headache, daytime drowsiness, dizziness, nausea, and a decrease in appetite.

Interestingly, the lights from our smartphones, tablets, and televisions can actually block our natural production of melatonin and contribute to insomnia. There are apps on phones and tablets that help filter out blue light. A better strategy, however, is to just keep your phone out of your bedroom.

Special thanks to Dr. Amy Atkeson for reviewing this article.

Marc Eisenberg, M.D., F.A.C.C.

Marc Sabin Eisenberg, M.D., F.A.C.C., is an associate professor of medicine at Columbia University Medical Center and an attending cardiologist at NewYork-Presbyterian Hospital.

Christopher Kelly, M.D., M.S.

Christopher Rehbeck Kelly, M.D., M.S., is a cardiology fellow at NewYork-Presbyterian Hospital / Columbia University Medical Center.