What Is Jet Lag?

Learn how jet lag impacts your mental health.

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What Is Jet Lag?

Jet Lag

Jet lag is a temporary sleep disorder that is caused by traveling rapidly across multiple time zones, due to a mismatch between your internal body clock and the local time of your destination.

Your body has a 24-hour internal cycle known as a circadian rhythm or body clock, that tells you when it’s time to sleep and when it’s time to wake up. Factors like sunlight and hormones like melatonin help set your body clock according to your location, so you sleep and wake up at the appropriate time for that location.

Jet lag typically occurs if you take a flight across more than three time zones because your body clock is still functioning according to your previous location and hasn’t caught up to the timings of your new destination.

This article discusses the symptoms, causes, and mental health effects of jet lag, as well as some prevention and coping strategies that may be helpful.

Physical Symptoms of Jet Lag

These are some of the physical symptoms of jet lag you may experience:

  • Fatigue
  • Lethargy 
  • Headache
  • Drowsiness 
  • Difficulty falling asleep or waking up
  • Poor sleep quality
  • Difficulty with everyday tasks
  • Stomach upset
  • Overall feeling of malaise

Traveling eastward is generally associated with difficulty falling asleep at the usual time whereas traveling westward is associated with difficulty waking up at the usual time.

Mental Health Effects of Jet Lag

While jet lag can be physically tiring, not getting enough sleep can also take a toll on your emotional and mental health. Not being in sync with the local time zone can be confusing and disorienting.

These are some of the mental and emotions symptoms of jet lag you may experience:

  • Irritability
  • Confusion
  • Disorientation 
  • Anxiety
  • Depression
  • Inability to concentrate
  • Lack of mental alertness
  • Lack of interest in food and activities

Causes of Jet Lag

When you travel to a new time zone, your body may have trouble adjusting to it because your circadian rhythm is still attuned to the timings of your previous location. As a result, you may be wide awake even though it’s dark outside and everyone else is sleeping. Or, you may feel extremely sleepy in the daytime when you’re supposed to be awake and functioning.

Jet lag tends to get more severe with each time zone you cross, due to a larger gap between your original time zone and the new time zone you’re in.

Jet lag also tends to be worse when you travel eastward as compared to westward, because you lose time when you go eastward and the day becomes shorter; by contrast, it’s easier for your body to cope when you go westward and the day gets longer.

In fact, apart from your sleep-wake timings, many of your other bodily functions are also synced to your circadian rhythm, such as your body temperature, hormonal activity, heart rate, blood pressure, and digestion.

Therefore, disrupting your circadian rhythm disturbs more than just your sleep cycle. For instance, you may feel hungry according to your mealtimes at your previous location, which may not align with your destination.

Jet lag can be worsened by factors such as:

  • Lack of sleep, due to irregular flight timings, for instance
  • Stress, which could be due to traveling or being in an unfamiliar place
  • Sitting in an uncomfortable position for long periods of time on an aircraft
  • Caffeine or alcohol use
  • Decreased air pressure or low oxygen levels in the aircraft

The severity to which everyone experiences jet lag can vary, but these are some groups that may be more likely to experience it:

  • Older people: While people of any age can experience jet lag, older adults may be more vulnerable to it. They may experience more severe bouts and take longer to recover.
  • Frequent travelers: People who frequently travel, such as business travelers, pilots, and flight attendants, may experience it more often due to their lifestyle.

Coping With Jet Lag

Jet lag typically can last anywhere from a few days to a few weeks—roughly one day per hour of time difference between your original location and new destination.

These are some strategies that can help you cope with jet lag:

  • Follow the timings of your destination: Do your best to follow the sleep-wake timings and mealtimes of your destination location. 
  • Expose yourself to light in the morning: Exposure to light helps your body reset your circadian rhythm. Expose yourself to daylight or bright light in the morning so your body knows it’s time to be awake.
  • Eat small meals: Avoid large, heavy meals and eat small, light meals instead, to prevent digestive discomfort.
  • Avoid alcohol: Avoid drinking alcohol, as it disrupts your sleep.
  • Consume caffeine strategically: Drink tea or coffee strategically during the daytime, to help you stay awake during the day. Avoid caffeine in the evening or night.
  • Avoid exercising at night: Stick to your regular exercise routine, if possible. Avoid exercising at night.
  • Stay hydrated: Drink plenty of water during the day to help you remain fresh and alert.
  • Take short naps: If you’re sleepy during the day and cannot stay awake, limit yourself to a short nap of 15-20 minutes. Setting an alarm can help ensure you wake up and don’t sleep away the day.
  • Try using a sleep aid: Sleep aids like melatonin can help you fall asleep at the right time per your destination. You can take three to five milligrams of melatonin half an hour before bedtime to help you fall asleep. Check with your healthcare provider to ensure it’s safe for you to use.
  • Postpone important events: If you have any important meetings or events, it may be helpful to postpone them until you feel better. Avoid making important decisions until you’ve recovered.

Preventing Jet Lag

If you have a trip coming up, these are some steps that can help you prevent or mitigate the effects of jet lag:

  • Start adjusting your timings before you travel: It can be helpful to start adjusting your bedtime and mealtimes to the timings of your destination before you travel, to make the transition easier. If you’re traveling eastward, try to go to bed an hour or two before normal. If you’re traveling westward, try to go to sleep an hour or two after your normal bedtime.
  • Set your watch in advance: It can be helpful to set your watch to the timings of the new location in advance, so you can start making the transition before you travel as well as on the journey.
  • Factor jet lag into your itinerary: Plan your itinerary taking into account the fact that you may be jet-lagged when you reach. As far as possible, try to avoid scheduling anything important within the first few days of reaching your new destination, so that you have a few days to recover.

A Word From Verywell

Traveling can be stressful enough without adding jet lag to the mix. Jet lag can make you feel tired, irritable, disoriented, and out of sorts. It can make it hard for you to function during the day and cause you to be awake at odd hours.

It can be helpful to plan ahead and factor the effects of jet lag into your itinerary to take some of the pressure off you when you arrive and give your body some time to adjust its rhythm to your destination.

8 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Sanjana Gupta
Sanjana is a health writer and editor. Her work spans various health-related topics, including mental health, fitness, nutrition, and wellness.