What Is Jet Lag?

By Brandon Peters, MD

Jet lag is a circadian disorder that transiently occurs after rapid travel across multiple time zones. It may be associated with other physical symptoms, including disturbed sleep. Learn about this common condition, its symptoms, and potential treatments.

If you have ever flown across a few time zones, you are undoubtedly familiar with the struggles of adjusting your sleep to the new hours. Why is jet lag, as it is called, so hard to tolerate and is there anything to be done?

First, it should be recognized that your body wishes to keep a regular sleep schedule. Certainly we are creatures of habit, and our bodies like when we go to bed and get up at the same time every day. Our biological clock, which is controlled by part of the brain called the suprachiasmatic nucleus, helps us to keep a regular schedule by releasing hormones on a regular pattern. This pattern is called a circadian—or “near day”—rhythm. Our sleep follows this same regular pattern.

When we disrupt the regularity of these cycles, our body treats us unkindly by making us sleepy or alert when we don’t wish to be. For example, if you were to go to bed three hours early tonight, you would have great difficulty falling asleep. However, if you fly from California to New York and crawl into bed at your normal bedtime, you are effectively attempting the same thing.

Causes

Rapid travel across multiple time zones leaves the circadian rhythms out of sync with the destination’s light-dark cycles. These rhythms affect sleep and wakefulness as well as metabolism, body temperature, and hormone release. It can take time for the internal circadian rhythm to be re-synchronized to external time cues. Jet lag is sometimes called desynchronosis, referring to the misaligned sense of time.

As a general rule, it is possible to adapt at an average rate of 1 hour per day. For someone who lives in California to fly to New York and cross three time zones, it would usually take 3 days to adjust to the new time zone. It is generally easier to travel westward and harder to travel eastward for most people.

Social jet lag may cause less intense symptoms and occurs in people who delay their bedtime and wake time by 1 to 2 hours on weekends and then have to correct as the work week resumes on Monday. This shift in the circadian timing may affect the start of the work week for several days.

Significance

In the new location, circadian signals may conflict with environmental and social cues in the context of jet lag. This may lead to a constellation of symptoms, including:

• Excessive daytime sleepiness

• Fatigue

• Insomnia

• Irritability

• Poor concentration

• Digestive problems (dyspepsia)

• Malaise (feeling unwell)

These symptoms may be disruptive and may be exacerbated by sleep deprivation, dehydration, sleep environment changes, and stress associated with travel.

Testing

The presence of the typical symptoms in the context of jet travel confirms the diagnosis without the need for further testing. In research, it is possible to measure an individual’s circadian pattern with tests that detect melatonin levels, often sampled from repeated saliva measurements. There are new blood tests also coming into clinical use that may identify the circadian rhythm.

Associated Conditions

Jet lag is most commonly associated with insomnia, defined as difficulty falling asleep or returning to sleep after waking. If insomnia occurs for less than 3 months, it is termed acute insomnia. As most people would be taking trips of a shorter duration than this, it could be grouped with other briefer disturbances of sleep. In some cases, jet lag may trigger a disruption that may evolve into a chronic form of insomnia.

Treatment

How can we counter our circadian rhythm when we travel? There are several techniques to reduce the effects of jet lag.

One solution would be to keep the same hours as our original time zone, going to bed and getting up based on the times at home.  his may not be the best way to enjoy our travels, especially if we fly great distances. An alternative would be to slowly adapt to the new time zone prior to leaving.

It may be possible to prepare the body gradually prior to departure by slowing adjusting bedtime and wake time to match the destination’s time. This can be done by adjusting our sleep by an hour for a week at a time. If we are crossing two time zones, the change can occur over two weeks. If traveling west, we would go to bed and get up an hour later for one full week. During the second week we would repeat the same, going to bed and getting up another hour later. If traveling east, we would go to bed and get up an hour earlier each week. If we can slowly adapt to the change, we will tolerate it better.  Unfortunately, unless the trip is quite lengthy, we wouldn’t be able to adjust the other way for our return home.This adjustment may be enhanced with properly time light exposure.

Light is one of the primary synchronizers of the circadian rhythm in sighted individuals. It may advance the timing of sleep earlier if the light exposure occurs in the 2 hours prior to the normal wake time or immediately upon awakening. Sunlight is best, but the use of light boxes or light therapy boxes may also have a role.

Beyond light, it may be important to address the symptoms that occur. Caffeine or strategic napping may relieve sleepiness. Other stimulant medications could also have a role. It may also be helpful to use hypnotic medications to aid sleep, including over-the-counter melatonin or prescription pills, such as:

• Zolpidem (Ambien)

• Eszopiclone (Lunesta)

• Zaleplon (Sonata)

• Ramelteon (Rozerem)

These medications to aid both wakefulness and sleep may ease the transition to a new time zone.

Conclusion

If you have a big trip coming up, you might plan ahead in how you can adjust your circadian pattern of sleep and wakefulness with some of the interventions outlined. This may help to optimize your experience while traveling to avoid the symptoms of jet lag.

Sources: 

Drake CL and Wright KP. Shift Work, Shift-Work Disorder, and Jet Lag. Principles and Practice of Sleep Medicine, 6thed., Philadelphia, Elsevier, 2017. pp.714-725.

American Academy of Sleep Medicine. International Classification of Sleep Disorders, 3rd ed. Darien, IL: American Academy of Sleep Medicine, 2014.

Gooley JJ. Treatment of circadian rhythm sleep disorders with light. Annals of the Academy of Medicine, Singapore. 37(8):669-76, 2008 Aug.

Sack RL. The pathophysiology of jet lag. Travel Medicine & Infectious Disease. 2009 Mar;7(2):102-10.

Sack RL. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. Sleep. 30(11):1460-83, 2007 Nov 1.

Srinivasan V, et al. Jet lag: therapeutic use of melatonin and possible application of melatonin analogs. Travel Medicine & Infectious Disease. 6(1-2):17-28, 2008 Jan-Mar.

How to Avoid Snoring on a Plane with Simple Treatments

Snoring on a plane is a common issue that many travelers face, and understanding how to manage it can significantly improve both your comfort and that of your fellow passengers. Several factors contribute to snoring while flying, but there are effective strategies you can adopt to reduce or even avoid it altogether.

DEHydration

To begin with, one fundamental approach to addressing snoring on a plane is to stay well-hydrated. The air inside an aircraft is notably dry, which can lead to dryness in the throat and nasal passages. This dryness can exacerbate snoring by causing the throat tissues to become irritated. To combat this, it’s advisable to drink plenty of water before and throughout your flight. Keeping a water bottle handy and sipping regularly can help maintain moisture in your throat and reduce the likelihood of snoring. Avoid caffeine and alcohol as these will lead to dehydration.

Nasal Congestion

Another key factor is managing nasal congestion, which can contribute significantly to snoring. If you’re prone to nasal congestion, such as might occur with allergies, using a nasal decongestant before your flight can be beneficial. Over-the-counter nasal sprays or decongestant pills can help clear your nasal passages and reduce inflammation, making it easier to breathe and decreasing the chances of snoring. It’s important to follow the instructions on these medications carefully to avoid any potential side effects.

Alcohol and Muscle Relaxants

Avoiding alcohol, sedatives, and muscle relaxants before and during your flight is another important consideration. These substances can relax the muscles in your throat, which can lead to a partial obstruction of the airway and increase the likelihood of snoring. By opting for non-alcoholic beverages and steering clear of sedatives, you can help keep your throat muscles from becoming too relaxed and minimize the risk of snoring.

Body Position

Your seating position on the plane also plays a crucial role in how likely you are to snore. Ideally, try to maintain an upright position if you can. This position helps keep your airway open and reduces the chances of snoring. If you need to sleep, use a neck pillow to support your head and keep it from tilting backward. This helps prevent your tongue and soft palate from collapsing and blocking your airway.

Breathing Exercises

Breathing exercises can also be beneficial in reducing snoring. Simple exercises, such as practicing deep, slow nasal breathing, can help open up your nasal passages and improve airflow. Additionally, strengthening the muscles in your throat through vocal exercises—like repeatedly saying “ahh” or making a singing sound—can help reduce the vibrations that lead to snoring. Incorporating these exercises into your routine before and during your flight can contribute to a quieter rest.

Breathe Right Strips and Snore Guards

For some travelers, using anti-snoring devices might be a practical solution. Nasal strips, which are applied to the outside of your nostrils, can help open your nasal passages and enhance airflow. Similarly, there are travel-friendly mouthpieces and snore guards designed to keep the airway open by repositioning the jaw. Even mouth tape may be an option to consider. While not all devices are suitable for every traveler, experimenting with these options might help you find a solution that works for you.

Additional Factors to Consider

Another method to counteract the dry air inside the plane is to use a portable humidifier, though this may not always be feasible during the flight. Instead, you might use a saline nasal spray to help keep your nasal passages moist. If a humidifier is not an option, these sprays can be a practical alternative for maintaining moisture in your throat and reducing the likelihood of snoring.

Maintaining a healthy lifestyle is a longer-term approach that can also impact your tendency to snore. Excess weight, particularly around the neck, can increase the risk of snoring. Regular physical activity and a balanced diet can help manage your weight and strengthen the muscles in your throat, thereby reducing snoring. Additionally, avoiding smoking can improve overall respiratory health and decrease the likelihood of snoring.

Finally, ensuring you get quality sleep before your flight is crucial. Being well-rested improves muscle tone and helps reduce the likelihood of snoring. If you find it difficult to sleep in noisy or bright environments, consider using earplugs or an eye mask to improve the quality of your rest. A full night’s sleep can help you wake up feeling more refreshed and less prone to snoring.

Conclusion

In summary, addressing snoring on a plane involves a combination of staying hydrated, managing nasal congestion, avoiding alcohol and sedatives, and maintaining an appropriate seating position. Breathing exercises, anti-snoring devices, and strategies to combat dry air can also be effective. By taking these steps, you can enhance your comfort and ensure a more pleasant flying experience for yourself and those around you.

This article was created using OpenAI’s ChatGPT on September 13, 2024 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.