We all know that tired, drained feeling after a long journey. The reason for this is often not just mere exhaustion, but jet lag. Jet lag is a sleep-wake cycle disorder caused by crossing multiple time zones in a short amount of time.
Jet lag symptoms such as fatigue, sleep disorders or loss of appetite can vary in intensity. If you don't want to spend the first few days of your well-deserved vacation fighting the symptoms, you should already take preventive measures. In this article we would like to show you what you can do against jet lag.
the essentials in brief
- Jet lag means a disruption of the sleep-wake cycle. This occurs when traveling across multiple time zones in a short space of time. The inner clock gets confused. For each time zone crossed, one speaks of one day that the body needs to get used to it.
- Typical jet lag symptoms are insomnia and fatigue. This is often associated with poor concentration, mood swings and headaches. Loss of appetite, digestive problems and general malaise can also be effects of jet lag.
- There are natural measures to prevent and combat jet lag. One effective way is to adjust your body to the new time zone before you travel. A healthy level of rest and exercise is also important upon arrival.
Definition: What is jet lag?
Jet lag is a sleep-wake cycle disorder caused by crossing multiple time zones.(8) Jet lag symptoms occur on long-haul flights where you cross three or more time zones. A maximum of 12 time zones can be crossed both to the east and to the west.
Jet lag is not the same as travel fatigue. The latter usually recovers after a good night's sleep. Jet lag is actually a disruption of the sleep-wake cycle. Because the body knows exactly when it is time to sleep or eat. To a certain extent, it thinks and functions in a 24-hour cycle.
It confuses the body when this rhythm no longer fits the external circumstances. This is precisely the case when several time zones are crossed during a journey. It can take several days for your body's internal clock to adjust to the new time zone.(1)
The extent to which jet lag affects your body depends on the number of time zones crossed. The more time zones you fly across on your trip, the more jet lag you will feel. On the other hand, the direction plays a role in how jet lagged you are. Traveling to the East is worse than traveling to the West.
Background: What you should know about jet lag
You have just found out when and how you can get jet lag in the definition. But there is a lot more worth knowing about jet lag that we don't want to withhold from you. In the following we will explain what that is in detail.
What are the symptoms of jet lag?
Jet lag means that crossing multiple time zones disrupts the body's sleep-wake cycle. The faster this happens and the more time zones are crossed, the more severe the symptoms usually appear. Difficulty sleeping and fatigue are the most prominent symptoms of jet lag. Feeling tired during the day and unable to fall asleep at night.
However, a number of other symptoms can also become noticeable when the body's internal clock gets messed up. Also common symptoms are:
- mood swings and irritability
- lack of concentration
- loss of appetite
- digestive problems
- General malaise
- dizziness and headache
Not all symptoms are inevitable. And when they do occur, they can vary in intensity and duration. This is an individual question. Older people and women suffer more from jet lag than young people and men.(6) The latter appear to be more adaptable to the transition. After an individual adjustment phase, i.e. as soon as the body has adjusted to the new time zone, the effects of jet lag disappear.
How long does jet lag last?
It can take several days, even one to two weeks, for the body to get used to the new time zone. A rule of thumb says that the body needs about a day for each time zone crossed to adapt to its own rhythm.
The effective duration of jet lag depends on several factors and can be influenced to some extent.
Important factors are, on the one hand, the duration of the journey and the direction of travel. The more time zones are flown over, the more jet lag affects the body. Accordingly, it takes longer for the body to recover. In addition, jet lag is more intense when crossing time zones to the east.
The duration of jet lag, on the other hand, depends on behavior before, during and after the trip. There are a few things you can do before you travel to help you get used to your destination. You can also take measures to prevent jet lag during the flight itself. And there are also ways to effectively combat jet lag at the travel destination itself.
Jet lag occurs when three or more time zones are crossed in a short period of time on long-haul flights. (Image source: Eva Darron / unsplash)
Furthermore, personal characteristics also have an effect on the duration of jet lag. Nocturnal people and those whose sleep-wake cycle is not too constant can adjust to new time zones more easily. Morning people and those with a fixed sleep routine have a harder time with this.
On which trips can jet lag symptoms occur?
Jet lag without a time difference is not possible. So if no time zones are crossed, there is no jet lag. For example, if you fly from north to south or vice versa, crossing fewer than three time zones, you will not experience jet lag symptoms. What you may then feel are travel strains.
Jet lag symptoms usually only become apparent when more than three time zones are crossed. This is the case when you travel west or eastbound.
Does east or west travel cause worse jet lag?
The effects on the body are more noticeable when you fly east. The reason is that the day gets shorter as you travel east. The body has bigger problems with this than if time is pushed back and the day is longer.
This is the case when traveling west. On the day of arrival when traveling west, the body simply has more time to adapt to the new conditions.(2) The body is said to need around 20 percent less time when traveling west to get used to the new time zone.
Can toddlers and pets get jet lag?
Whether young children suffer from jet lag depends on whether they already have a fixed sleep-wake cycle. This is not yet the case for babies up to the sixth month. They do not yet have an internal clock and therefore cannot suffer from jet lag.
However, children with a regulated sleep-wake cycle can experience jet lag just like adults. The severity of the symptoms also depends on individual factors in children. They can vary in intensity and last a long time. As a rule, however, children overcome jetlag faster than adults because their own sleep-wake cycle is simply not as pronounced.
Domestic animals and farm animals also suffer from the time change. Similar to humans, animals can also have a sense of time and an internal clock. Cows, for example, get used to fixed feeding and milking times. But pets such as dogs and cats also recognize recurring activities and adapt to them from now on.
Animals also suffer from jet lag when their usual rhythm is disrupted. They also need a few days to adjust to the new time zone. The most common symptoms in animals are restlessness and insomnia.
Do melatonin tablets help against jet lag?
The body produces the hormone melatonin, which ensures a good and restful sleep. Consequently, more melatonin is released in the dark than during the day when it is light. The sleep hormone is formed in the pineal gland in the diencephalon and then goes into the blood. From here, it triggers fatigue.
Anyone suffering from jet lag can take melatonin tablets to normalize the disrupted sleep-wake cycle. In terms of quantity, you should stick to a dose between 0.5 and a maximum of 5 milligrams. The tablets should be taken just before bedtime or an hour or two before.
However, the effect of melatonin tablets is not clear.
Some studies prove their effectiveness, others dispute them.(4.5"> Side effects and long-term consequences are also unclear.(1.2"> It is therefore advisable to first consult specialists such as doctors or pharmacists.
That's why we recommend taking melatonin tablets as a last resort. There are other ways to prevent and combat jet lag. We will then show you what they are.
As an alternative to the melatonin tablets, you can also try regular sleeping pills such as valerian or Z-Drugs to level off your sleep-wake cycle. However, you should try it the natural way first, because sleeping pills also affect your organism and can confuse the body.
Is jet lag a reason for disability?
In principle, jet lag is not a sufficient reason for incapacity to work. However, if jet lag triggers serious sleep disorders that last for several days, it is advisable to see a doctor. If the psychological strain is correspondingly high, a career break can be ordered in such a case.
Sleep disorders impair performance and the ability to concentrate. Because if you don't sleep enough, you're tired and exhausted. Chronic sleep problems often have their roots in the psyche: stress, pressure at work or bullying can be triggers for sleep disorders.
In summary, tiredness and a bad night are not enough to be (temporarily) declared unfit for work. However, if jet lag causes sleep disorders, a doctor should analyze your situation. If necessary, they can release you from work for a few days.
Tips against jet lag: With these measures you can effectively prevent and combat jet lag
The body's internal clock gets scrambled when you cross multiple time zones on long flights. This is perfectly normal. Your sleep-wake cycle gets messed up. It takes time for the body to get used to the new conditions.
You can positively influence this process with targeted measures before, during and after the trip. If you don't want to suffer from jet lag symptoms for long while on vacation, you should read the following sections carefully. We will show you effective ways to combat jet lag.
Maintain your own sleep-wake cycle
One way to combat jet lag is to maintain your own sleep-wake cycle. However, this is only indicated for short trips. If you're not going away for more than three or four days, that makes perfect sense. Because the body needs energy to adapt to a new rhythm. The effort is not worth it for short trips.
With this method you are pursuing the goal of avoiding double jetlag. Short trips across several time zones harbor the risk that the jet lag from the outward journey has not yet been completely overcome and new symptoms appear on the return journey. This messes up the body twice.
In preparation you have to calculate the time difference between your destination and your home country. In this way you can then determine sleeping and eating times in the travel destination, which you should definitely adhere to. So you must not adapt to the new circumstances.
Adapt sleep-wake cycle to new time zone
If your trip lasts longer than several days and you cross several time zones in a short time, then adjusting your sleep-wake cycle to the new time zone is the right strategy for you days before departure.
| travel direction | Preparation |
|---|---|
| east | Time is advanced on long journeys to the East. For your preparation this means: Go to bed an hour earlier and get up an hour earlier every day. |
| west | Time is turned backwards on long journeys west. For your preparation, this means: go to bed an hour later every day and get up later. |
With the adapted sleep-wake rhythm to the destination, you should also adjust your meal times accordingly. This makes it noticeably easier for you to get used to the new time zone after the flight, because your internal clock has already adjusted to some extent.
Also, note that if you don't want to be plagued by severe jet lag symptoms at home, you'll need to adjust your sleep-wake cycle before heading home. So towards the end of your trip you should try to get your internal clock used to the time at home.
Behave properly on the flight and after arrival
There are a number of things you can do on the flight and in the days following your arrival in the new time zone to reduce or combat jet lag symptoms. These are in particular:
- Set time to destination
- Drink water, but avoid coffee and alcohol
- Expose yourself to daylight and create darkness
- Find a balance between rest and exercise
In the following you can read what the individual measures include and why they are effective against jet lag.
Set clock to destination
If you adapt your sleep-wake cycle to the time zone of your travel destination, then you should already change your clock accordingly on the plane. This will help you to adjust your behavior to the new time zone.
If it is night time in your destination during the flight, you should try to sleep on the flight. This will help you get used to the day-night rhythm of the new time zone more quickly.
If you orientate yourself according to the new sleep-wake cycle during the flight, it will also be easier for you to go about your normal daily routine in the first few days after landing.
When it's time to sleep at your destination, an in-flight nap will help combat severe jet lag symptoms. (Image Source: Annie Theby / unsplash)
Those who cannot sleep well when traveling by air can prevent jet lag by choosing the right flight time. Choose the flight so that you arrive at your destination in the evening. Then stay awake during the flight so you can go to sleep in the new time zone.
Drink water, but avoid coffee and alcohol
In general, when traveling by air, it is important to drink enough water or juices. The dry air in the cabins has a dehydrating effect on the body and mucous membranes. The longer the flight length, the more liquid you should drink.
Drinking enough water also helps against jet lag, because not drinking enough water increases the symptoms. So it would be counterproductive if you nullified the measures taken against jet lag because you didn't drink enough water. Your water balance should not only be at a healthy level on the flight, but also in the days after arrival.
Negative in trying to stay hydrated is ingesting fluids that dehydrate your body. This is the case with alcohol, but also with caffeinated beverages such as coffee and black tea. It is therefore advisable to avoid a glass of wine with food or coffee in the morning until your body has adjusted to the new time zone.
Expose yourself to daylight and create darkness
As already seen, the body produces the sleep hormone melatonin. When it's dark, more of it is poured out that you get tired. Less of it is produced in daylight, so you stay awake. With daylight and darkness you can control the release of melatonin to a certain extent.
Regardless of whether you stick to your own sleep-wake cycle or adapt to the new time zone: Fresh air is good for your body. The daylight also helps you overcome fatigue. Because it inhibits the release of melatonin.
Conversely, you should ensure that your room is completely darkened at night or during bedtime. Darkness naturally stimulates melatonin production. This should make it easier for you to stick to your bedtime when it's dark.
Find a balance between rest and exercise
Jetlag triggers symptoms such as tiredness, poor concentration, mood swings and headaches. In this respect, it is advisable that you take it easy for the first few days at the travel destination. Avoid stress and take it easy. Moderate activities have a positive effect on acclimatization. Find the right balance between relaxation and exercise for you.
Not overexerting your body doesn't mean you shouldn't be active at all. On the contrary. A little exercise after a long journey is even necessary for the body to avoid thrombosis. Don't push him too hard, though, especially if you're feeling tired and listless.
But if you have trouble falling asleep, a light exercise session can work wonders and be so exhausting that you fall into bed tired in the evening.
Conclusion
It's perfectly normal for the body's internal clock to get confused when crossing multiple time zones. Jetlag is the effect of this and can vary in severity. But now you know what measures you can take to effectively combat jet lag symptoms.
So before you travel, think carefully about whether you want to adapt your sleep-wake cycle to the new time zone or whether you want to keep it. Then try to adapt and stick to this rhythm. If you then behave in an exemplary manner on the trip yourself, the vacation can begin without delay and annoying side effects.
References
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