Jet lag

What is jet lag? | Jet Lag Symptoms | What causes jet lag | How to prevent jet lag? | Practical Tips | Conclusion on jet lag

Long-haul flights in themselves are usually not that pleasant: hours of sitting with limited legroom, no fresh air and a lot of time in a small space with many people. As if that weren't enough, there is also a special physical strain due to long flights: jet lag.

Jet lag is a disruption of the sleep-wake cycle. This happens because his body's internal clock deviates from the local time at the destination. In order for this deviation to be noticeable, this only occurs on long-haul flights over several time zones (minimum 3 hours)

Jet lag can disrupt sleep and cause other annoying symptoms that linger for days after the flight, negatively impacting your travel, whether private or business.

Knowing about the symptoms and causes of jet lag and ways to reduce it can make traveling to distant lands more enjoyable.

What is jet lag?

Jet lag is a disruption of the circadian sleep-wake cycle. This disorder occurs when the internal 24-hour clock, called the circadian rhythm or cycle, does not match the local day-night cycle.

A person's circadian rhythm aligns with daylight. It promotes alertness during the day and sleep at night. This internal clock synchronizes with the 24-hour day to promote sleep quality and physical and mental health. Geographical location clearly has an influence on the circadian rhythm here, since the times for sunrise and sunset are location-dependent.

Jet lag usually only occurs when traveling east or west across three or more time zones. If you fly from Munich to Islamabad, Pakistan and arrive at 8pm, your body may still function as if it were in Munich at 5pm. This jet lag can result in staying up later than you would like or feeling more tired than usual.

Common symptoms of jet lag

The most common jet lag symptoms include:

Difficulty sleeping:
For one thing, falling asleep can be harder or you wake up earlier than you should. Jet lag can also cause sleep to be fragmented into restless sleep phases.

Daytime sleepiness: Jet lag often leads to feeling sleepy and tired during the day.

Impaired Thinking: You may have problems with attention or memory, or simply feel like your thinking is slowing down.

Impaired Physical Function: Peak physical performance may be impaired because the body feels tired

Emotional Difficulties: Some people with jet lag feel irritable.

Stomach problems: Jet lag can lead to gastrointestinal problems such as loss of appetite, nausea or even constipation and irritable bowel syndrome. [1]

People with jet lag suffer from one or more of the above symptoms. Symptoms can appear immediately or a few days after arrival. Interestingly, many travelers sleep well the first night after a flight, only to have trouble sleeping for the next few days.

Jet lag can last from a few days to a few weeks. rule of thumb; Jet lag symptoms last 1 to 1.5 days per time zone flown through. From Munich to New York this could then take 6 to 9 days.

But: the duration of the symptoms varies from person to person.

Can jet lag have long-term consequences?

Jet lag is usually a short-term problem that goes away once the body's circadian rhythm adjusts to local time. For people who frequently take long-haul flights, such as pilots, flight attendants, and frequent business travelers, jet lag can become a chronic problem

A chronically out-of-sync circadian rhythm can lead to persistent sleep problems, which in turn can lead to insomnia. A healthy internal clock is important for the overall health of the body.

Jet lag factors

Most people experience jet lag worse when traveling east than when traveling west. This can be explained by the fact that it is generally easier to delay the internal clock than to advance it.

Jet lag does not occur on north-south flights such as Munich to Johannesburg that do not cross multiple time zones.

Not everyone who takes a long-haul flight gets jet lagged. Several factors affect the likelihood and severity of jet lag:

Trip Details: Total distance, number of stops, time zones flown, direction of travel, local daylight hours, length of stay at destination can all impact the duration and severity of jet lag.

Arrival time: The time of arrival at the destination can affect the circadian rhythm. For trips to the east, there is evidence that jet lag is lower for afternoon arrivals than for early morning arrivals.

Sleep before the trip: Poor sleep in the days before a flight can increase the likelihood of jet lag after a trip.

Stress: When you're stressed, your mind and body can become tense in ways that interfere with sleep and make it harder to manage jet lag.

Alcohol and coffee consumption: Many people drink alcohol and coffee during the flight. Both substances can disrupt sleep.

Many factors play a role in jet lag. Therefore, it is very difficult to predict who will develop jet lag, how severe it will be, and how long it will last. But it's safe to assume that at least a little bit of jet lag will occur if more than three time zones are crossed during the flight.

How to prevent or reduce jet lag?

Jet lag can spoil the first few days of a vacation or business trip. Therefore, travelers strive to minimize the effects of jet lag.

The key to combating jet lag is to quickly adjust your daily rhythm to the time zone of your travel destination. Until that is achieved, there are steps you can take to relieve symptoms.

The following sections cover methods for readjusting circadian rhythms and practical tips for reducing jet lag.

Light against jet lag

Light has the strongest influence on the circadian rhythm. Targeted lighting can help set your internal clock to avoid or reduce jet lag.

Sunlight has the highest degree of illumination and the strongest circadian effects. Various types of artificial light can also affect the circadian rhythm to a lesser extent.

Properly timed periods of daylight and darkness can help synchronize circadian rhythms with local time. When access to natural light is limited, light therapy lamps can provide bright illumination with a greater impact on the circadian clock.

Melatonin against jet lag

Melatonin is an endogenous hormone that helps make you feel sleepy and controls your circadian rhythm. Normally, melatonin is produced in the evening, a few hours before bedtime, but this schedule can be thrown off by jet lag.

Studies confirm that melatonin is suitable as a sleep aid and can reduce the time it takes to fall asleep [1] and in some cases also increase total sleep time and improve sleep quality [2].

Change your sleep schedule in advance

A slightly more involved method of preventing jet lag is to adjust your sleep schedule in the days leading up to your trip so that when you arrive at your destination, there is less of a discrepancy between your circadian rhythm and local time.

In addition to changing bedtime, this approach often also involves the use of melatonin and light exposure to proactively alter circadian rhythms.

However, this approach may not be feasible depending on your daily routine and your work, family, and social commitments.

Practical tips to reduce jet lag

A number of practical tips before, during and after your flight can help reduce sleep disturbances and jet lag:

Reduce jet lag before departure

Planning the first days of the trip:
Make sure you get enough sleep. Add buffers to your schedule in case you're feeling sluggish, and try to arrive a few days before an important meeting or event if possible. This gives you time to acclimate.

Minimize travel stress:
Don't wait until the last minute to pack or head to the airport. Hurrying can add to the stress and make the journey more difficult.
Get a good night's sleep: Make sure you get a good night's sleep at least a few nights before your trip so you don't start out sleep deprived.

Reduction of jet lag during flight

Drink enough:
Drink water to stay hydrated and to counteract the dehydration that can occur during the flight.

Limit alcohol and coffee:
Reduce alcohol and caffeine intake on board. Or better yet, leave it out altogether.
Eat healthy and light:

Reduce the risk of digestive problems with a healthy and light diet. Eat fruit and vegetables rather than heavy, high-calorie, and greasy foods.

Get up and move: Blood clots and stiffness can occur if you sit for too long. Walking, standing and slightly stretching a few times during the flight can reduce these risks.

Reduction of jet lag after arrival

Exercise: Take time for a walk or other light physical activity. Outdoor exercise with adequate daylight hours helps rebalance your circadian rhythm.

Avoid alcohol, caffeine and heavy meals: Avoid excessive consumption of caffeine and alcohol as well as heavy and high-calorie meals.

Resist the temptation of long naps: Avoid the temptation to take an extra long nap. Try to limit naps to less than 30 minutes.

Conclusion on jet lag

Jet lag can be annoying and can easily ruin the early days of your long-awaited vacation. But: If you follow a few tips, the effects can be minimized so that you can fully enjoy your stay or vacation. Just don't go full throttle immediately after arrival, but move and relax. And with a melatonin spray as a little sleep aid, you should be able to have a jetlag-free holiday quickly.

Sources

[1] https://pubmed.ncbi.nlm.nih.gov/28648359/
[2] https://pubmed.ncbi.nlm.nih.gov/23691095/