Jet lag has a nasty habit of turning what should be a once-in-a-lifetime experience into something that 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 Toronto to London at 7pm your local time. But, owing to the five-hour time difference, that means your flight is leaving at 12am the following morning in the UK. You arrive at 8am local time, but, for you, your internal clock thinks it’s now 3am. This shift between time zones could 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 a plane's cabin 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: 

• Sleep disturbances

• Digestive disturbances

• Headaches

• Irritability

• Decreased physical performance

• Decreased mental performance

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

28 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 travellers 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 University of Montreal suggests that you need between 12 and 24 hours to recover from one hour of time difference. 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 cited by the Canadian Sleep Society has shown that approximately two-thirds of international travellers experience signs of jet lag, but anyone can 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 travellers jetting off across the world for one reason or another. According to the latest tourism activity stats released by the government, Canadians alone made 42.9 million visits abroad in 2024. If we use the figure above, that means approximately 28.3 million of them experienced jet lag.

5. Eastwards is harder to acclimatize to than westbound

Those travelling to the east – who’ll be losing hours – are found to have a harder time acclimatising to their new timezone than anyone headed in the opposition direction. This is because it’s easier to delay sleep than it is to force it.

6. Older travellers are more susceptible 

It’s bad news for those seeing the world in their twilight years. Seniors are likely to feel the effects of jet lag more acutely, needing more time to recover, so factor this into your plans if you’re an older traveller.

7. More than half of Canadians would sacrifice a week’s vacation for a better bed

We’ve all been there. Sometimes the excitement and energy expended on a trip away means we come back mentally recharged, but physically wiped out. A national survey reveals 53% of Canadians would give up a week’s luxury vacation for a better bed. One third would pay up to $500 for a week’s worth of quality rest.  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. 

8. Despite its impact, jet lag is not the only contributor to sleep loss

As we’ve seen, jet lag can have a monumental impact on how well we sleep when we travel. But it’s not the only contributor to a poor night’s rest when we’re off on our adventures. You may experience something called the first night effect, when only half the brain enters deep sleep. The other half remains alert because you’re in an unfamiliar location, meaning you don’t feel as rested.

9. Business travellers lose close to an hour of sleep a night

Travelling 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 travellers 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. Worrying about the outcome of a business meeting may also have an effect, especially since jet lag can reduce our concentration and decision-making, both important elements of our working lives.  

10. 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 travellers, 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. And even those travelling for leisure aren’t immune, with 45% worrying about post-vacation fatigue before they’ve even returned home. 

11. 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.

12. 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.

13. Disruption to normal rhythms was the next biggest factor

The same survey found that 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. 

14. 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. The same survey found that 5% of people said they struggled to comfortably keep food down after returning home or arriving in a new location.

15. 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.

16. Sleep routine takes a lot longer to bounce back

In less positive news, your circadian rhythm and bedtime routine might take a bit longer to go back to normal. The same Oura research 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 begin to gel properly again. This was especially true after longer trips to the east.

17. 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. Lack of sleep makes it more difficult for us to regulate our emotions and worsen any existing symptoms of anxiety and depression. That can have a huge impact beyond returning to normal sleep patterns, with it dragging into your day-to-day life.

18. Losing sleep can leave you more stressed

If jet lag does strike on your travels, it can leave you feeling a little more on edge during your time away. Multiple studies have shown a link between lack of sleep and stress, with one feeding into the other. So, if you haven’t had enough sleep you’re more likely to feel stressed, and if you already feel stressed you’re more likely to lose sleep.

19. 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. Sleep deprivation means we’re more likely to experience depression, or struggle with physical health conditions like heart disease. 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.

20. 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.

21. 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 USD in 2024 (approximately $604.15 million CAD), having been rapidly driven forwards by the evolving use of technology and tools within the sleep management sector.

22. 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 USD (approximately $604.15 million CAD) to $619.3 million USD (approximately $848.22 CAD) in that time.

23. Sleep tourism is something people are keen to try

As if that wasn’t already enough, a lot of travellers 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. One survey found that 77% of people want to go on a sleep tourism trip, while 98% considered good sleep to be a vital part of their vacation.

24. Many people will pay more for a sleep enhanced room

Such is the weight being placed on a good night’s rest, that travellers are willing to go as far as to pay more for a room which has been designed with enhancing the sleep experience in mind. 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 USD (approximately $2397.31 CAD).

25. 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%).

26. But sleep tourism can also be domestic

Despite the clear desire for travellers to get out and see more of the world at a slower pace, sleep tourism can also be a domestic pursuit. Canadian residents took 90.6 million trips that included a domestic visit in the second quarter of 2025 alone, up by 10.9% compared to the previous year. While we don’t know how many of these trips included a sleep tourism element, it shows there’s an appetite for travel within our borders.

27. 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 USD ($204.05 billion CAD) 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 10 actionable tips to try when you’re next travelling 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 20-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. A common recommendation is to drink eight 250ml cups of water per day, but the right amount is really down to the individual. 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 travelling 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 travellers – particularly those flying for business – to adopt their usage. A recent report found that 69% of people travelling 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 10-to-20 minutes at maximum and avoid napping too close to bedtime. A 3pm cut-off point is ideal.

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 melatonin was added to the Prescription Drug List in Canada in 2025, and some countries have restrictions on how much melatonin you can use to drift off. 

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.