Jet lag has a nasty habit of turning what should be a once-in-a-lifetime experience into something which you occasionally have to power through. For those taking long treks between vastly different timezones, adjusting your body clock can make all the difference when it comes to the overall enjoyability of your time away. 

In this data-driven guide, we’re going to take a closer look at what you need to know about jet lag to better understand and, ultimately, beat it. If you’re wondering how to perfectly balance travel, having fun, and getting the optimum amount of sleep while you’re adventuring, be sure to read on.

What is jet lag?

First and foremost, let’s get a better grounding for what it means to actually be jet lagged. First coined by the LA Times in a news article way back in 1966, those experiencing jet lag have had their internal clock – or "circadian rhythm” – disrupted as a result of hopping across one or multiple different timezones. 

Think of it this way: you take off on a flight from San Diego to Barcelona at 7pm your local time. But, owing to the time difference, that means your flight is leaving at 3am the following morning in Spain. 

You arrive at 11am local time, but, for you, your internal clock thinks it’s now 3am. This shift between time zones will leave you groggy and extremely tired – especially if you weren’t able to sleep on the flight.

What causes us to become jet lagged?

As you can imagine, knocking your circadian rhythm out of whack like this can have a huge impact on how awake we feel. Your sleep-wake cycle will struggle to adjust for a short period after travel of this nature, and it can have a wider impact on things like the time of day when you’re hungry, or even when you might need to use the bathroom. 

The amount of sunlight we receive also plays a large role in our body’s ability to function properly. Light can regulate a number of hormones inside of us – but arguably the most important of these is a sleep-supporting one known as melatonin. 

The more light we experience during the day, the less melatonin we can produce. That means if you are exposed to bright natural (or fake) light for extended periods of time, your body won’t register that it needs to produce the hormone to help you fall asleep. 

While less common of a cause, the air pressure inside of a cabin of a plane can also trigger jet lag. Dry air conditions inside the plane will lead to you feeling more dehydrated, which can impact how your body functions. 

What are the symptoms of being jet lagged? 

Most of us know that jet lag will make us feel a lot more tired when we arrive at our destination. But this is far from the only adverse effect which you might feel. Aside from a feeling of extreme tiredness, other symptoms which have commonly been associated with jet lag are: 

• Headaches

• An inability to concentrate 

• A queasy feeling like an upset stomach 

• Mood shifts and a feeling of being low or easily irritable 

• Trouble falling asleep when you try to 

• Drowsiness during daylight hours 

The type of jet lag you experience is going to differ depending on whether you travel east (where you gain hours) or west (where you lose them).

Losing hours might mean that you find it tough to fall asleep, as you try to adjust to a new schedule. Gaining hours might make it harder to stay awake during the day, as this could be a time when your body would normally be asleep. 

30 Important facts about the impact of jet lag and its relationship with sleep 

Now that we have a better understanding of what jet lag is and how it might impact someone on their travels, it’s time to take action. The best way to do that is by understanding the nuances of this pesky flying phenomenon. Let’s dive into these 30 eye-opening facts to make getting your head around jet lag a breeze.

1. Jet lag can start before you fly 

Kicking things off with something less fun, research from the NUS Yong Loo Lin School of Medicine shows that jet lag symptoms can actually begin to surface before you step on a plane. Oura summarized the findings of the school, highlighting that waking up earlier than normal for morning flights meant that some travelers already found themselves at anywhere from a 30-to-50-minute disadvantage when it came to staving off the condition.

2. It takes more than a day to adapt for every timezone you’re in 

Remember how we mentioned the importance of your circadian rhythm when dealing with jet lag? The Sleep Foundation suggests that every time you cross from one timezone to another, it will take your body as much as 1-to-1.5 days to recover. This isn’t a hard-and-fast rule, with the length of time it takes to fall back into your normal routine differing person to person.

3. More than two-thirds of people experience jet lag when they fly long haul 

If you do find yourself experiencing the unpleasant side effects of jet lag, at least take some solace in knowing you’re not alone.  Research has shown that as many as 68% of international travelers who fly regularly will experience some form of it during their time away. That means for every 10 people traveling long haul, almost seven of them will struggle with symptoms at some point after they get off the plane.

4. Over 100 million people get jet lag every year 

And if that wasn’t already an eye-opening amount, the total numbers for global annual jet lag reports are even more stark. A whopping 100 million people are believed to experience jet lag every year, with this number only set to rise as more business and personal trips are taken by travelers jetting off across the world for one reason or another.

5. Eastwards is harder to acclimatize to than westbound travel for short trips

Those traveling to the east – who’ll be gaining hours – are found to have a harder time acclimatizing to their new timezone than anyone headed in the opposition direction. A Science Daily report found that those moving eastwards found it harder to adjust over shorter flights (where only a few timezones might be crossed over). For longer flights, there was less of a noticeable difference, with the average for both directions seeing an average shift of 60-to-70 minutes between sleeping times. 

6. Older travelers are less susceptible 

It’s good news for those seeing the world in their twilight years. The same study showed that those aged 60 and above experienced a smaller immediate impact when it came to the reduction in sleep levels during the first few post-travel days of their trip. When compared directly with a 20-year-old, it was found they lost 15 minutes less of sleep than their elders. 

While the number doesn’t sound that extreme, the net difference could be huge. Seniors are thought to need an average of just 7 hours sleep every day, compared to the 8.5 that young adults aged 18-25 might need. 

7. A quarter of Americans avoid long haul flights 

Sleep Review Magazine found that 23% of people in the US would put off taking a long haul trip to avoid getting jet lagged.

8. More than half will ignore jet lag because of FOMO

The same study also found that most Americans are willing to buckle up and push through in order to get the most out of life. FOMO, or “fear of missing out”, was enough to see at least 53% of respondents say they were willing to ignore the groggy feeling and headaches in order to see more of the world. That despite 42% also saying that they found coping with symptoms of jet lag to be a big challenge.

9. Jet lag means people often need a vacation from their vacation 

We’ve all been there. Sometimes the excitement and energy expended on a trip away means we come back mentally recharged, but physically wiped. Reports show that as many as 79% of travelers come back from a vacation feeling like they need another one just to recover. Jet lag plays a huge role in this, with the adverse feelings leaving many feeling like they need extra time to get their circadian rhythm back in check before they face the perils of a working day.

10. Despite its impact, jet lag is not the main contributor to sleep loss

As we’ve seen, jet lag can have a monumental impact on how well we sleep when we travel. But would it shock you to know that it’s only the second biggest contributor to a poor night’s rest when we’re off on our adventures? Amerisleep found that the biggest barrier to sleep when away from home was actually uncomfortable pillows or mattresses. 

57% of respondents said this was their biggest hurdle for getting enough rest, with jet lag (40%) in a three-way tie in second spot with loud neighbors and noise from the hallway, as well as staying up too late because of vacation FOMO (fear of missing out). 

11. Business travelers lose close to an hour of sleep a night 

Traveling for business already comes with its own struggles. Being away from home and having to work at the same time isn’t something many people actively enjoy. Those issues can sometimes be compounded by the startling numbers regarding how much sleep these kinds of travelers tend to get. 

Reports show they average just 5 hours and 17 minutes of sleep a night, with the typical loss per person sitting at around 58 minutes. While this isn’t solely down to jet lag, the jump between timezones will unquestionably have a huge impact on those figures.

12. A fifth of those are concerned about jet lag even after they get home 

Jet lag isn’t just something which goes away the moment you arrive home. And for business travelers, the reality of feeling groggy both during and after the trip is a real concern. One in five report this as a stressor for any work trip, with as many as 36% going as far as to say jet lag was a major concern in general for any business meeting overseas.

13. The immune system can get weaker after just a few days of poor sleep 

Have you ever noticed that you tend to catch a cold slightly more often after getting back from a long trip? Research shows that travelers experiencing sleep disruption for just 2–3 nights can have a 30% reduction in natural killer (NK) cell activity, a key component of the immune system. 

This makes them more susceptible to infections such as colds or travel-related illnesses. Couple that with the amount of people you’ll be sharing a cabin with, and the chances of picking up a cold thanks to your jet lag go up.

14. Fatigue is the most common symptom of jet lag 

We’ve already briefly touched on the different kinds of symptoms that people will experience when they’re jet lagged. Perhaps to not great surprise, a feeling of immense fatigue and tiredness was the most commonly experienced. 50% of respondents in an In Tech Open survey said that this was the factor which had the biggest impact on them when battling jet lag.

15. Disruption to normal rhythms was the next biggest factor 

28% would say that it was the long-term impact of jet lag on their circadian rhythm which was the hardest to deal with. This disruption to normal patterns of sleep might not have as an immediately noticeable impact, but it can be something which takes longer to recover from after you get back from a vacation.

16. Some people even struggle to eat when jet lagged 

The shift in timezones, as well as the queasy feeling which some of us get after our sleep falls out of its normal rhythm, also meant that a small handful of people found eating to be the biggest jet lag-related issue. 5% said that they struggled to comfortably keep food down after returning home or arriving in a new location. 

17. Sleep duration tends to recover quickly 

In encouraging news, the amount of time we sleep has been found to bounce back relatively fast. Oura found that the amount of sleep someone gets every night was able to rebound to within 12 minutes of their normal baseline within just two days of returning back to normal life at home. For savvy vacationers, that means building in a weekend after your trip to recover will see you in good shape by the time you head back to work on Monday. 

18. Sleep routine takes a lot longer to bounce back 

In less good news, your circadian rhythm and bedtime routine might take a bit longer to go back to normal. The same source said that those wanting to get back into their usual routine after a trip might have to wait anywhere up to 15 days before things began to gel properly again. This was especially true after longer trips to the east.

19. A lack of sleep can have a huge impact on wider mental health 

The crux of the issue is that a lack of sleep brought on by jet lag can have a big effect on your overall mental health and wellbeing. Reports suggest that as many as 46% of people experience a big dip in their overall mental health as a result of missing sleep. That can have a huge impact beyond returning to normal sleep patterns, with it dragging into your day-to-day life.

20. Losing sleep can leave you more than twice as stressed 

If jet lag does strike on your travels, it can leave you feeling a little more on edge during your time away. Research shows that a lack of sleep can leave you feeling as much as 2.5 times more stressed than you would on a regular day. This kind of level was commonly experienced by those who got less than 6 hours of sleep on a given night.

21. Sleep issues commonly precede periods of feeling low

What’s more, falling out of our circadian rhythm puts us in a position where we’re slightly more susceptible to other mental health and wellbeing issues. A study from Harvard showed that people who regularly struggle to get enough sleep were four times more likely to develop a serious mental health condition.

22. For some, travel actually means more chances to sleep 

Interestingly though, jet lag isn’t always a factor for those who travel. In fact, in some cases the hop between timezones seems to have the opposite impact. A study has shown that those who might usually be classified as “underslept individuals” actually got more sleep while they were on their travels, whereas those who regularly got more than 7.5 hours a night tended to see their total hours of sleep dip.

23. The jet lag therapy market is now worth billions

A variety of techniques and preventative measures used to combat jet lag are often grouped together under the banner of “jet lag therapy”. This includes supplements, as well as light therapy.  This market reached a whopping $441.1 million in 2024, having been rapidly driven forwards by the evolving use of technology and tools within the sleep management sector.

24. The market is expected to grow further in the future 

And this looks like it’s only the beginning for the wider market. Forecasted figures show just how much of a factor the need to battle jet lag has become, with predictions from the folks who crunch the numbers suggesting that from 2025 through to 2033, the value of these transformative treatments and preventative measures is expected to grow at a rate of 3.73% per year. That would see the total value jump from $441.1 million to $619.3 million in that time. 

25. Sleep tourism is an alternative which one in five people are now trying out 

As if that wasn’t already enough, a lot of vacationers are now also taking the power of sleep back into their own hands. Sleep tourism is a new phenomenon where people are actively seeking out places to go and get the rest and relaxation they need as an intrinsic part of their time away. It’s thought that as many as 20% of all travelers are expected to go on this kind of trip at some point on an annual basis.

26. A lot of people will pay more for a sleep enhanced room 

Such is the weight being placed on a good night’s rest, that travelers are willing to go as far as to pay more for a room which has been designed with enhancing the sleep experience in mind. The same survey found that 43% of respondents were willing to hand over more money to make sure that they weren’t going to see their overall sleep quality levels suffer. In total, it’s thought that those on a sleep tourism getaway were willing to spend an average of $1,752.

27. Italy, Japan, Greece and the Maldives lead the way for sleep tourism

The best spots to try this revolutionary new form of tourism? Well, you’ll find them dotted all over the globe. From Asia to Africa, Europe to North America, there is a wide array of serene destinations which tourists looking for tranquil travel are trying out. 

Kyoto in Japan ranks first, with 19% of respondents saying they’d give this historic cultural hub a try. The islands of Santorini in Greece (14%, the Amalfi Coast in Italy (13%), and the Maldives (11%) were the next most popular. When it came to North America, Big Sur in California led the way with 8% of responses, followed by its neighbour the Napa Valley (8%) and Arizona’s desert town of Sedona (7%). 

28. But nearly two-thirds of sleep tourism is domestic

Despite the clear desire for travelers to get out and see more of the world at a slower pace, the bulk of sleep tourism is still more of a domestic pursuit. Market research shows that close to two-thirds of sleep tourism happens in the form of staycations, with 63% of people going on this kind of vacation choosing to stick within their own borders.

29. The sleep tourism market is another which is expected to see major growth 

Just like with the growing popularity of jet lag therapy, the market for sleep tourism looks ready to steamroll on. Many estimate as much as 12.4% of compound annual growth in the sector between now and 2030, with its total value rising to $148.98 billion in that time if those figures turn out to be correct.

10 Ways you can prevent jet lag from becoming a factor on your trip 

Now that you’ve got a better grasp of how and why jet lag can have such an impact on a trip away, it’s time to take the power back. While there’s no guaranteed way to make sure jet lag doesn’t impact you in some capacity, there are plenty of tricks to help reduce that unwanted feeling of lethargy or grogginess. Here are eight actionable tips to try when you’re next traveling on a long haul flight.

1. You can prevent jet lag by sleeping earlier before travel 

Our first snippet of advice is to gradually adjust your sleep schedule prior to the date of your trip. This doesn’t have to be anything dramatic. Something as simple as going to bed 15 minutes earlier (if you’re headed east) or later (if you’re going west) every night for around two weeks prior to your trip will have a big impact. Also think about doing the same thing when it comes to when you eat. Getting your circadian rhythm in line with your new timezone can mitigate several potential hours of lost sleep.

2. Consider arriving a few days early, or building in rest days 

If you’re going away with a specific purpose in mind, such as a business meeting or to attend an event, planning to arrive a little before the time you need to is another smart idea. Most of the more extreme symptoms of jet lag will slowly wear off after a few days in a new timezone, which gives you a window to turn up, get to grips with them, then start to feel more like yourself again in time for the main purpose of your trip. If there isn’t a specific event you’ve travelled for, these extra days will still give you a chance to guarantee you’re experiencing your vacation to its fullest.

3. Manage your bright light exposure 

We’ve already discussed how getting too much exposure to light can keep you awake when you might want to sleep. But, naturally, the opposite can also be true. Even just getting outside for 10-to-30 minutes can help provide enough vitamin D and melatonin suppression to make sure you’re feeling awake enough to take on the day.

4. Staying hydrated can reduce the impact of jet lag

Keeping up your hydration levels is another way to make sure you’re doing what you can to stave off some of the more challenging symptoms. It’s thought that the average human man needs about 15.5 cups (or 3.7 litres) of water a day to keep their body functioning at top capacity, while a woman needs 11.5 cups (2.7 litres). Making more of a concerted effort than you usually would to drink during travel, as well as the days before and after. If it helps, you can set reminders to drink every hour or so.

5. Change your watch before you travel 

While it won’t have the same impact from a physical perspective, changing your watch to the timezone you’re traveling to can help to make the transition between them a little easier. Starting this a few days before you travel will also give you a rough idea of what your body feels like during times when you might need to eat or sleep in your travel destination. You can find the timezone you’ll be visiting online.

6. Consider an app which helps to prevent jet lag 

More awareness than ever exists around how and why we need to battle jet lag. As a result, there are now plenty of apps which exist to make drifting off to the land of nod faster than ever before. And there’s a clear keenness from travelers – particularly those flying for business – to adopt their usage. A recent report found that 69% of people traveling for this reason were either already using these kinds of apps, or intended to start using them in the future.

7. Try not to nap for too long when you arrive (particularly eastwards) 

It might be tempting to catch a little shut eye when you travel (especially if you’re moving eastwards, where your body will feel like you’ve lost sleep). But doing this can actually keep your internal clock out of rhythm for longer. If you feel like you absolutely have to sleep, try to cap it at 15-to-30 minutes at maximum.

8. Melatonin has emerged as one remedy for those unable to sleep on their travels

We’ve already discussed how melatonin plays a big role in the ease with which we fall asleep. If you find that you’re struggling to drift off, it’s now possible to buy melatonin supplements which can make falling asleep faster. 78.4% of respondents in a recent study said that using the hormone supplement helped them, with it having a peak impact on them after roughly one hour after usage. Just be aware that while melatonin is available over the counter in the US, it is prescription-only in some countries.

9. Tasimelteon is another alternative 

An alternative to melatonin is the supplement tasimelteon. This was found to increase total sleep time in participants of a study by as much as 85 minutes per night. It was also found to improve next-day alertness (the time it took to wake up and feel ready to face the day) by as much as 15 minutes.

10. Light therapy can also battle jet lag

Light therapy is another option for those wanting to improve sleep time. While this is more useful after returning from a trip, it still plays an important role in making sure sleep patterns return to healthy levels. The process sees the use of special light boxes, or dawn simulators, which can help to trigger the body’s ability to manage its own circadian rhythms.