As we begin to see the light at the end of the COVID pandemic tunnel, people are feeling safer about doing things that used to be natural and frequent — like traveling. In fact, what the media calls “revenge travel” — traveling more to make up for the lack of time on the road during the pandemic — is leading to increased road trips and longer lines at the airport.

Whether you are traveling for the first time in a long time or have consistently been on the road during the past year, you know that jet lag can be a disconcerting speed bump when you travel by air. Known to the scientific community as circadian desynchrony, more than 90% of travelers experience jet lag when they move from one time zone to another, and it can be a real obstacle to physical and mental health at a time when you need to be alert and well-rested.

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What is Jet Lag?

Jet lag is a temporary sleep disorder that occurs when you travel quickly — usually by air — from one time zone to another. Moving across a single time zone most likely won’t trigger it, but more than that and you may find yourself fatigued and feeling vaguely unwell. Jet lag can cause gastrointestinal issues and problems with concentration and alertness. 

Jet lag is caused by several factors. Crossing two or more time zones disrupts your circadian rhythms — the internal clock that tells your body what time to wake up and go to sleep. For example, if you are used to going to bed at 10 p.m. in your Los Angeles apartment and then fly to New York City, which is four hours ahead, your circadian rhythms won’t think it’s time for bed until 1 a.m., NYC time.

Another influence on jet lag is sunlight, which is the primary influence on your circadian rhythm. The retina of your eye registers light and, during the day, sends a message to a part of your brain called the hypothalamus. The hypothalamus then tells your pineal gland to hold onto a hormone called melatonin and not release it into the body. Melatonin is one reason you’re able to sleep soundly, so lack of it may keep you awake.

A third factor with jet lag is related to the conditions on your plane. As any air traveler can tell you, the air in a plane is dry and lacking humidity. It can also be stale and leave you feeling dehydrated. Add that to the fact that your body is experiencing numerous changes in cabin pressure during the flight, and you have one more reason why you may feel off after a long flight.

Jet lag tends to be more severe the more time zones you travel through and the longer your flight. There is also evidence that it is more difficult to negotiate for older individuals than for younger adults and children. 

What Are Jet Lag Symptoms and How Long Do They Last? 

So how do you know if you have jet lag? If you have been on a plane and crossed several time zones, the probability is that you will have it. Here is what you can expect in the way of symptoms:

  • Disrupted sleep pattern. Either you will not be able to sleep, will sleep for too long, or your sleep will be disturbed. This is probably the most common symptom of jet lag.
  • Fatigue during the day. Until your circadian rhythm adjusts to the new time zone, you may feel tired during daytime hours.
  • Not feeling well. Imagine this to be as if you had a head cold or the flu but without the congestion. You may feel achy or just not up to your usual standards of health.
  • Having a hard time getting through the day alertly. You may have trouble concentrating; if you’re in a group, it may be hard for you to contribute to the conversation.
  • Mood swings or general crankiness. You may feel annoyed about things that usually don’t bother you or find yourself short-tempered when dealing with others.
  • Gastronomic issues. You may experience either constipation or diarrhea or be uninterested in food.

Symptoms tend to worsen the more time zones you’ve passed over, and they may also be slightly worse if you are traveling west to east. A general rule of thumb is to expect to feel unwell for one day for every time zone you go through. So that LA-to-NYC trip may leave you with some symptoms for up to four days.

How To Prepare For Your Trip 

You prepare for your trip by buying tickets and packing your bags. But are there things you can do ahead of time to prepare for jet lag? Preventative measures can indeed make a big difference, and they start with those tickets. If possible, schedule your flights to avoid long layovers in between your departure and arrival time zones. If you can book a flight home to arrive at bedtime, you’ll avoid sun exposure that would throw your circadian rhythm off even more. 

Can you sleep on the plane? For some people, this just doesn’t happen, but if you are able to get some shut-eye when propped up in an economy seat, then book a night flight and sleep while you’re in the air.

There are a number of companies that sell sleep aids for those who want to sleep while in-flight, from neck pillows to personal air fresheners to face masks. Invest in whatever item helps you to sleep deeply on the plane. Try them out in the comfort of your bedroom at home beforehand, so you’re used to them before boarding time.

Also, consider changing your schedule gradually. If you’re heading east, set your bedtime to half an hour earlier each night for a few nights before you leave. Reverse the procedure if you’re traveling west. One trick: try setting your watch to the new time zone a few days ahead of time, too, to help you remember when to sleep.

Another tactic worth trying is the Argonne Anti-Jet-Lag Diet, developed by a biologist, Dr. Charles Ehret, and used by the military. It advocates alternating days of high-protein feasting with days of comparative fasting, with a fast before arrival and then another high-protein feast after you arrive. There aren’t many studies available online to validate this diet, but anecdotally it has seen some success.

How Can You Beat Jet Lag?

Is it possible to avoid jet lag after a long flight? Maybe not, but there are tactics you can take to reduce the severity of your symptoms and the length of time you suffer from them. Here are a few tips for the casual traveler to consider (we’ll look at frequent flyers in the next section):

  • Stay hydrated. Before and after your travels, make a point of drinking more water, tea, or other drinks than you might normally. During the flight, when the cart comes your way, ask for bottled water and sip it throughout the flight.
  • Avoid alcohol. Keep your drinks to those that are non-alcoholic, however. It’s tempting to think that a glass of wine or two either during or after the flight will help you relax and sleep, but alcohol dehydrates you — which causes jet lag in the first place. Alcohol also leads to disrupted, poor-quality sleep.
  • Stay away from caffeine, too. If you’re used to a cup of coffee in the morning, by all means, have it. But don’t binge on coffee or soda in an attempt to stay awake when your body is telling you to sleep after a long flight. That will only disrupt your circadian rhythm even more.
  • Schedule lightly. If at all possible, cut yourself some slack and plan for a light schedule the first day or so after a long flight. If you can’t do that, consider flying to your location a day earlier than you need to be there so that you can have a quiet day on your first day in the new location.
  • Get outdoors when you arrive. Get some sun as soon as you can after arriving. This tells your internal clock to begin the work of resetting to the new time.

Spotlight on Frequent Flyer Jet Lag 

If you are a frequent flyer, either for work or pleasure, then jet lag is probably an old, unwelcome friend for you. When you can, take advantage of all of our suggestions above. In addition, however, here are some tips for hard-core travelers who face jet lag frequently.

  • Take melatonin. Melatonin is available as an over-the-counter drug, and studies show that it may be helpful in letting you sleep during times when you’d normally be awake — which is what can happen after a west-to-east flight. Take a 0.5mg pill to start about 30 minutes before you go to bed — or ask your doctor to recommend a schedule.
  • Light therapy. The Mayo Clinic recommends that you start light therapy three days before travel, exposing yourself to the sun, or using a portable lightbox. If you’re going east, get your sun in the morning. If west, go for evening light. 
  • Exercise. There is anecdotal evidence that a solid run the morning after you travel can help your internal clock reset itself more quickly and painlessly. Studies have been done with animals that suggest that cardiovascular exercise works to reduce the time spent in a jet-lagged state and restore your circadian rhythms in half the time it would otherwise. During the flight, meanwhile, remember to stand and stretch regularly, even taking a walk down the aisle if you’re able to.
  • Eat wisely. Avoid heavy, hard-to-digest meals right before and during your flight. Light snacks that are fruit- or veggie-based are a better bet than anything that is fatty or overly salty.
  • Use an app. Changing your sleeping schedule may, of course, leave you tossing and turning. Consider using a sleep app to provide relaxing sounds, melodies or meditations to help you wind down and prepare your mind and body for restful slumber. There are also apps designed specifically for jet lag — one we like is at — that help you maximize your schedule to smooth out the bumps of traveling over time zones.

Having Trouble Sleeping In Unfamiliar Places? 

Travel, by its very definition, means that you’ll be sleeping in unfamiliar places, whether it’s on the plane, in a friend’s home or hotel room, or even back in your own bed after a long trip. And that often means disrupted sleep — partly due to jet lag and partly because studies show that part of your brain “stands guard” when you’re sleeping in new spaces. 

How does this happen? Researchers have measured slow-wave activity, which occurs in the brain when you’re asleep. During your first night in a new place, they found, the slow-wave activity was greater in the right hemisphere, meaning that part of the brain was half-awake. This is most likely an evolutionary trait that dates back to the days when humanity had many predators, and it was a benefit to be able to half-listen for signs of them while asleep.

The most logical solution for a troubled night’s sleep after travel, of course, is to travel a day early and dedicate your first day in a new location to laying low and allowing yourself to adjust. The second night, studies have shown, is generally better, and a single, lightly scheduled day can be enough to get you back on track.

Avoid naps if you can, however — which also holds true for jet lag in general. Your goal should always be to support your body as best you can in its efforts to adjust to the new light-dark configuration of a different time zone. The best way to do that is to allow yourself to sleep only during the night if you’re able. If you absolutely must close your eyes during the day, make it a short, 20-minute power nap rather than a three-hour snooze, which will only confuse your circadian rhythms even more.

Here’s The Punchline 

Although some jet lag may be unavoidable after a long trip, this doesn’t mean you’re at its mercy. Try some of our suggestions — before, during, and after the trip — to ease the symptoms of jet lag, and incorporate those that work for you into your regular travel routine. The last thing you want to do when you, say, fly to Paris for your first post-pandemic vacation is to be laid up for five days feeling terrible and getting little sleep. By taking advantage of small adjustments to your travel plans, you may instead be ready to go within a day or so, alert and refreshed after a good night’s sleep.