Coronavirus (COVID-19)

COVID-19 Vaccines  |   Visitor Policy  |  What to expect when visiting Mercyhealth  |     Mercyhealth FAQ  |  CDC FAQ  |  Antibody Testing Information  |  COVID-19 Lab Testing  |   Virtual Visit... continue reading

Health Library

Return to Index
by Kerr SJ

Preventing Jet Lag

eating on a plane image If you have ever traveled across multiple time zones, you are probably all-too-familiar with the sleepiness, fatigue, and headaches of jet lag. For a long time, jet lag was considered to be something that was all in your head. Now, research has shown that jet lag has real, biological causes.

Not Just in Your Head

Your body has in internal clock. It controls your body temperature, blood pressure, hormone levels, and other biological processes. This clock helps determine when you sleep and wake. When you fly across time zones, your internal clock gets out of sync with your new location. This means you may feel sleepy during the day or wake up in the middle of the night. Jet lag may cause:
  • Fatigue
  • Difficulty concentrating
  • Trouble sleeping at night
  • Weakness
  • Clumsiness
  • Headache
  • Stomach ache, lack of appetite
Jet lag does have a biological cause, and knowing the cause can help you know how to prevent it.

Stay One Step Ahead of Jet Lag

If you wait until you arrive at your destination to think about jet lag, it may be too late. Try some of these suggestions before your next big trip.

Rest Up

Preparing for a vacation or business trip can mean a flurry of last minute errands, phone calls, and packing, but make sure you get enough rest. Starting your trip tired can mean you never get back on track—not a fun way to spend a vacation or be successful on a business trip. As much as possible, get plenty of rest before take-off. Try getting a headstart on the time change by staying up an hour later (if you are traveling west) or going to bed an hour earlier (if you are traveling east) for several days before your trip.


Before and during your flight, make sure you are getting plenty to drink. Stick to non-caffeinated, non-alcoholic beverages, since caffeine and alcohol can act as stimulants. Dehydration can make sleepiness and fatigue worse.

Plan Ahead

If you are travelling across many time zones, plan your trip knowing that you will most likely have some jet lag. Keep the schedule light for the first 2 days of your trip to give yourself some time to recover. If you can, choose a flight that allows you to arrive at your destination in the early evening. Then, try to stay up until 10 pm local time to help your internal clock adjust to the new time zone.

On Arrival

After you arrive at your destination, you can take steps to help with symptoms of jet lag.

Get on Schedule

Adjust your daily routine to fit the new time zone as soon as possible. When you arrive, change your watch to coincide with the new time zone. Even if you feel tired during the day, try not to sleep. If you must nap, limit it to no more than 2 hours.

Get Outside

Get outdoors into natural light. Sunlight will help your internal clock adjust more quickly.
Melatonin is a hormone found in the human body that helps regulate sleep. Your body produces melatonin according to the amount of light you are exposed to.
Melatonin supplements have gotten a lot of attention as a possible cure for jet lag. However, the evidence from clinical trials examining melatonin is inconsistent. Melatonin has been shown to be effective if you are crossing more than 5 time zones traveling east (losing 5 hours), but it may not have a noticeable effect if you are only traveling across a few time zones. Melatonin may even be harmful if you have epilepsy or take warfarin, so talk to your doctor if you are considering taking it.
When you travel, you may want to wear a sleeping mask when you sleep to make sure your body is producing enough melatonin to help you adjust to your new time zone and stave off jet lag. Your body will produce more melatonin in a dark room than in one that is dimly lit.

Get Some Sleep

When it is finally time for bed in your new time zone, you might find it difficult to sleep. New and unfamiliar noises can keep you awake even if you are very tired. Try some white noise: a fan, air conditioner, or even a radio on static can block out those unfamiliar noises and help you sleep. If those are not available, you can download an app on your phone or tablet.
Experiencing some jet lag is probably unavoidable, especially if you are traveling over many time zones. Do your best to be well-rested before your journey begins, and make sure to get enough rest throughout your trip. There may not be a quick fix, but a few simple steps and some planning can keep severe jet lag at bay.


American Academy of Sleep Medicine
National Sleep Foundation


Better Sleep Council of Canada
Health Canada


Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. 2002(2): CD001520.
Jet lag. Centers for Disease Control and Prevention website. Available at: Updated April 21, 2013. Accessed April 16, 2015.
Jet lag and sleep. National Sleep Foundation website. Available at: Accessed April 16, 2015.
Jet lag: what you should know. Am Fam Physician. 2006;73(10):1808.
Melatonin. EBSCO Natural and Alternative Treatments website. Available at: Updated December 15, 2015. Accessed April 21, 2017.
Melatonin for jet lag. EBSCO DynaMed Plus website. Available at: Updated June 2, 2010. Accessed April 16, 2015.

Revision Information

Mercyhealth MyChart Sign In
is the if statement working?