Staying healthy on holiday | Understanding and avoiding jetlag when you fly

When the body's internal circadian rhythms fail to synchronise with the local time zone, we’re left feeling exhausted and disorientated. If you’re a frequent flyer, you’ve likely felt jetlagged at one point or another.

Jetlag can be an issue for anyone, from holidaymakers and pilots to aircrew and commercial clients. Find out more about why jetlag occurs and what you can do to avoid it, below.

If the right precautions aren’t taken, the body and mind can take time to adapt which can have an impact on the enjoyment of your holiday or the success of your business ventures.

The key takeaways

  • Find out whether you’re going to gain or lose time on your flight
  • Sleep as you fly to help your body clock adjust naturally to a new time zone
  • Take a sleep aid like melatonin the night of your landing to help reset your sleep cycle
  • Stay hydrated to avoid dehydration worsening your fatigue
  • For long haulers, arrange a flight that lands in the morning so you can sleep as you travel.

What is jetlag?

You may find that when you land after a long flight you are ready to sleep, despite it being mid-morning in the country you are now in. This is because your body is still operating on your home time zone, where it might be late evening.

Jetlag refers to a set of symptoms usually associated with sleep and tiredness that can occur when we fly into a new time zone. Because our mind and body use the sun to structure our day, entering a different time zone can throw our internal natural rhythm out of sync.

Thankfully, symptoms are usually temporary and can be easily addressed. Take a look below to find out more about jetlag and to understand what you can do before you fly, on the flight and after you land to avoid the worst of it.

What can I do about jetlag?

Because there are degrees of jetlag, it can be difficult to address without knowing how severe the issue is. Thankfully, there are some basic things everyone can do before they fly, in the air, and when they land.

Before you fly

  • Limit light exposure: our circadian rhythm naturally associates light exposure with being awake. Where possible, limiting light exposure in the hours before you fly can help trick the body into feeling more tired, giving you a better chance of sleeping on your flight.

During your flight

  • Stay hydrated: take as much water on as you can. If you’re on a long flight, this will save you money and ensure you’re not tempted by the on-flight liquid refreshments. Staying hydrated by sipping water frequently helps replace the additional water the body loses at altitude
  • Avoid caffeine and alcohol: whilst this is easier said than done for many of us, caffeine and alcohol only serve to confuse our circadian rhythm further. The best option for staying hydrated on a long flight is water or a diluted soft drink
  • Stretch your legs: like dehydration, remaining sedentary in your seat can cause stiffness, fatigue and circulation issues. Where possible, we recommend taking regular breaks to get up and stretch
  • Get some sleep: try and sleep on a flight that lands in the AM in your new time zone. Then try and stay awake and fall asleep at night. Conversely, on a flight that lands at night, try not to sleep on the flight. Taking melatonin at night on your day of landing can help aide sleep.

After you land

  • Try your best to stay awake: even if you’ve slept in flight, you can still feel the effects of a long day spent in the air. If you land in the day, don’t schedule anything too strenuous that day and try and get a good sleep that night. This gives you time to wind down and acclimatise to your new time zone
  • Get some sun: our circadian rhythm reacts positively to sunlight which reinforces our desire to stay awake. If you’re tired and looking to stay awake, getting out in the sun is a great way to stave off fatigue and keep your head off the pillow
  • Melatonin: taking melatonin the night of your landing can help aide sleep and reset your sleep cycle. If you’re holidaying, this is a great way to ensure fatigue and tiredness don’t impact the rest of your holiday.

What are the common symptoms of jetlag?

Jetlag typically affects sleep because the body is still operating on your native time zone. Depending on whether we’re flying east or west (moving backwards or forwards in time), you may find it easier or harder to adjust. Symptoms also vary depending on how far you’re travelling and whether you’re a frequent flyer.

Take a look below for some common signs and symptoms of jetlag:

  • Waking fatigue: you may feel more tired than usual in the few hours after landing
  • Difficulty falling asleep: if you’re flying in the evening and moving forward a few time zones, you may even find falling asleep difficult if you are landing in the evening or at night
  • Irritability: a lack of sleep can cause irritability and touchiness
  • Insomnia: if you sleep on the plane flying west, you may find it difficult to fall asleep the night you land
  • Difficulty concentrating: a disrupted sleep schedule can make concentrating on anything difficult. This can have major consequences if you’re travelling for work.

What are circadian rhythms and why are they important?

Almost all living organisms have a circadian rhythm. This set of internal processes follow a 24-hour cycle and are physical, mental, biological, and behavioural. They are entirely natural and typically respond to light and dark, which is why we feel naturally drawn to sleep at night and to wake in the morning with the sun.

You might have heard people describe themselves as a “night owl” or “not a morning person”. Chances are, this is out of their control. No two body clocks are the same, meaning we all need slightly different amounts to function properly.

Everything from hormones to the detailed function of our cellular makeup plays a part in regulating our circadian rhythms. Unfortunately, one thing millions of years of evolution hasn’t quite adjusted to is air travel. Whilst we all love to reap the benefits of travelling through multiple different time zones within the space of a few hours, this can wreak havoc on our natural circadian rhythm if we aren’t careful.

Your inflight checklist

If you’re not used to longer flights, consider adding some of the following to your inflight luggage:

  • A comfortable blanket and neck pillow
  • As much drinking water as you are allowed
  • Earplugs or good quality noise-cancelling headphones
  • Healthy snacks to avoid unhealthy inflight refreshments.

How long does jetlag last?

How long jetlag lasts depends on several factors, including how far you’ve travelled, how well you prepared for jetlag and your overall body health and how this typically affects your circadian rhythms.

Jetlag can last days if your body clock requires a few sleep cycles to climatise to a new time zone fully.

If you’re a frequent flyer who’s used to moving between time zones, or you find jetlag doesn’t affect you too badly, you may find staying up when you land and getting a good night’s sleep is enough for you.

Does your direction of travel affect the severity of jetlag?

Yes, the direction you’re travelling in makes a big difference to how you experience jetlag. Travelling west prolongs your body clocks sleep routine, meaning you can adjust easier by simply staying awake a few extra hours.

Flying easterly makes it harder for your body to adjust to your new time zone, as you’re travelling “against” your body clock, which disrupts your natural circadian rhythm.

Can children experience jetlag too?

Children are not immune to jetlag and can even experience it worse than adults. This is because children find it more difficult to cope with disruption to their more regimented sleep schedules than adults do.

If you can avoid taking children on long-haul flights, you should. If they have to fly and already suffer with sleep problems, consider speaking with a GP or healthcare professional before they fly.

What if I’m travelling for work?

If you have a meeting the day you land, it’s vital you sleep on the way over. Turning up to a business meeting tired and fatigued doesn’t help anymore, and only means you will inevitably crash hard afterwards. Regardless of when you land, prioritise taking melatonin that night to ensure you get some shut eye the night of your landing. This will encourage sleep and help to reset your sleep cycle ahead of your busy schedule the following day.

If you regularly fly long-haul for work and are finding jetlag to be an issue, consider speaking with your GP about practical methods you can use to combat tiredness and fatigue in line with your busy schedule.

Last updated Tuesday 1 August 2023

First published on Tuesday 1 August 2023