How to Adjust to a New Time Zone and Avoid Jet Lag

Light Exposure, Medications May Adjust Your Circadian Rhythm

Learning how to adjust to a new time zone to avoid jet lag is helped by light exposure
Learning how to adjust to a new time zone to avoid jet lag is helped by light exposure. Funky Illustrations from Holland/Moment/Getty Images

If you have traveled a considerable distance, the last thing you want to deal with is jet lag. How do you avoid jet lag? More to the point, what is the best way to adjust to a new time zone? If you can learn how to adjust to a new time zone, with light exposure and medications as needed, you will enjoy your travels all the more.

Lessons in How We Sleep Can Improve Jet Lag

First, it is important to understand why we feel sleepy when we do.

This is dependent on two processes: homeostatic sleep drive and circadian rhythm. The sleep drive is our desire for sleep; the longer we stay awake, the sleepier we become. This is due to the build up of a chemical in the brain called adenosine. The circadian rhythm complements this and also dictates the timing of our sleep. This nearly 24-hour rhythm encourages us to sleep when we do. It is the circadian rhythm that is most impacted by travel.

The circadian rhythm is something that our brain generates in an area called the suprachiasmatic nucleus. This is close to the optic nerves that perceive light, and light is the strongest factor controlling our circadian rhythm. (This will become important later.) There are other weak influences called zeitgebers (or "time-givers"). These include the timing of meals, the temperature of our environment, and other social cues (like other people being awake at certain times).

When we abruptly change time zones, there is a dramatic shift in our exposure to light and misalignment of our body’s sense of day and night and the new environment occurs.

Time Zones and Direction of Travel Become Important

The sudden disruption of our circadian rhythm that occurs with jet lag can be distressing.

The number of time zones that we cross is key. Traveling across the country and changing only a few time zones is generally well tolerated, but long flights crossing oceans and continents can prove more challenging. In general, it can take one day for each time zone changed to adjust. For example, if you have traveled across 5 time zones, it may take up to 5 days for your circadian rhythm and sleep to fully adjust.

The speed of travel can also play a role. If you are taking an airline flight or a leisurely drive, the effects of passing through time zones can be quite different. This is due to the time that the travel itself takes. A long car trip takes more time, leading to synchronization between the time it takes to travel and the slow change of time zones, allowing an easier transition to occur. If it takes 10 hours to pass through a time zone while driving, then you have essentially allowed a half day to accommodate to the shift.

The direction of travel has an important role, too. Many people say, "East is a beast, west is best." This acknowledges that traveling in a westward direction is often easier for people to tolerate because it is easier to shift the circadian rhythm later.

To think about it another way, consider how easy it is to stay up a few hours later in the night and how challenging it can be to wake up that much earlier in the morning.

How to Adjust to New Time Zones

If you find yourself traveling a great distance, you may want to learn how to adjust to a new time zone. Few people may plan ahead, making a gentle transition by gradually shifting their sleep schedule (bedtimes and wake times) before departing home to anticipate the new time zone. Most people get on a plane and deal with the consequences when they get there.

This abrupt reset can be somewhat difficult.

The most common symptoms associated with jet lag include poorly aligned sleepiness (during the day) and wakefulness (with insomnia at night), headache, and stomach upset. Fortunately, there are some interventions that can help ease the transition.

The most important factor in resetting your body clock is light exposure. As indicated above, it has the strongest control over your circadian rhythm. It is best to get 15-30 minutes of direct sunlight exposure immediately upon awakening. Go for a walk, sit on the patio and read the newspaper, or have breakfast outdoors. You will find that keeping a regular bedtime and wake time with morning light exposure will help a great deal. 

Medications may also have a role to play in aiding this change. A low dose of melatonin several hours before your desired bedtime may help align your circadian rhythm to the new time zone. Higher doses may also aid sleep if taken at bedtime. Other sleeping pills can also be helpful to ease the transition. Sleepiness during the daytime can be counteracted by caffeine, strategic naps, and even stimulant medications in extreme cases. It is important to avoid drowsy driving while adjusting to the new time zone.

Another way to really build up a desire for sleep is to extend your period of wakefulness. This will generate a very robust sleep drive and may counteract some of the issues related to a misaligned circadian rhythm. Much like pulling an all-nighter, your desire for sleep will be exceptionally strong if you stay awake for a prolonged period, no matter what time zone you find yourself in. You might try to limit the amount of sleep you get on your flight, so that you are sleepier, and stay up once you have arrived until you reach your normal bedtime based on local time.

As your trip winds down, you should be mindful of your return to the prior time zone. If you can ease yourself into the change by gradually adjusting your bedtime and wake time in 30-60 minute increments towards the new clock setting, it will be easier. If not, you can always follow the same advice outlined above to adjust to the new time zone at home.


Kryger, MH et al. "Principles and Practice of Sleep Medicine." Elsevier, 5th edition. 2011.

Continue Reading