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Jet lag disorder

  • Overview


    When you travel across multiple time zones quickly, you may experience jet lag, also known as jet lag disorder. This temporary sleep issue affects anyone. Your body has an internal clock called circadian rhythms, which signals when to stay awake and sleep. Jet lag occurs because your internal clock remains synced to your original time zone and is not adjusted to the new time zone of your destination. The more time zones you cross, you will likely experience jet lag. Jet lag may cause daytime fatigue, sickness, difficulty staying alert, and stomach problems. However, there are steps you can take to help prevent or reduce the effects of jet lag, making your vacation or business trip more comfortable.

  • Symptoms


    Jet lag symptoms can vary significantly from person to person. You may experience only one or several symptoms, including difficulty falling asleep or waking up too early, daytime fatigue, inability to focus or function normally, stomach problems such as constipation or diarrhea, a general feeling of unwellness, and mood changes. The severity of symptoms can be worse the farther you travel, especially if you fly east. These symptoms typically occur within a day or two after travelling across at least two time zones and may take approximately one day to recover for each time zone crossed.

  • When to see a doctor


    Jet lag can take a toll on your body, but the good news is that it’s only temporary! However, if you’re someone who frequently travels and experiences the dreaded jet lag, it might be worth looking into seeing a sleep specialist. They can provide helpful tips and tricks to combat jet lag and get you back feeling like your energetic self in no time.

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  • Causes


    Crossing multiple time zones can disrupt your circadian rhythms, also known as your internal clock that regulates your sleep-wake cycle. This can result in jet lag, which can occur at any time. For instance, if you depart from New York at 4 p.m. on Tuesday and arrive in Paris at 7 a.m. on Wednesday, your internal clock will still believe it is 1 a.m. This means you will feel like sleeping when Parisians are waking up.

    It usually takes a few days for your body to adjust to the new time zone. During this period, your sleep-wake cycle and other body functions, such as hunger and bowel habits, will remain out of sync with the new location. Sunlight is a significant factor that affects circadian rhythms by influencing the release of melatonin, a hormone that helps cells in the body work together. When there is low light, the hypothalamus in the brain signals the pineal gland to release melatonin, while the opposite occurs during daylight hours.

    It is essential to expose yourself to the proper timing of light, which is crucial to your internal clock, to help ease the adjustment to a new time zone. However, changes in cabin pressure and high altitudes during air travel may also contribute to some symptoms of jet lag, regardless of the time zone. Additionally, the low humidity levels in planes may lead to dehydration, which can also contribute to some symptoms of jet lag.

  • Risk factors


    Several factors increase the likelihood of experiencing jet lag, including crossing multiple time zones, flying east and being a frequent flyer. Older adults may also need more time to recover from jet lag than younger individuals.

  • Prevention


    You can take a few simple steps to prevent or minimise the effects of jet lag. If you have an important event that requires you to be alert and focused, consider arriving a few days early to allow your body time to adjust. Getting plenty of rest before your trip is essential, as starting sleep-deprived can exacerbate jet lag symptoms. Gradually changing your schedule before you leave can also help. If you’re travelling east, try going to bed an hour earlier each night for several nights before your trip. If you’re heading west, go to bed an hour later for a few nights beforehand.

    Additionally, try to eat meals at times that correspond to your destination’s time zone. Light exposure is crucial in regulating your body’s circadian rhythms, so it’s important to time it properly. If you’re travelling west, exposing yourself to light in the evening can help you acclimate to a later time zone. Conversely, morning light exposure can help you adjust to an earlier time zone if you’re heading east. However, if you’ve travelled more than eight time zones to the east, it’s best to wear sunglasses and avoid bright light in the morning. If you’ve travelled west by more than eight time zones, avoid sunlight a few hours before dark for the first few days. Once you arrive at your destination, set your watch or phone to the local time and try to sleep during the local nighttime, regardless of how tired you feel. It’s also important to stay hydrated by drinking plenty of water and avoiding alcohol and caffeine. If it’s nighttime at your destination, try to sleep on the plane using earplugs, headphones, and eye masks to block out noise and light. If it’s daytime, resist the urge to sleep. By following these tips, you can help minimise the effects of jet lag and enjoy your travels to the fullest.

  • *Please note that the information provided in the article is for reference purposes only. It is essential to consult a doctor before applying any of the suggestions mentioned.

Content Details

Medical info from Mayo Clinic, for reference only. Visit Hoan My for better advice.

Last updated on: 14/08/2023