Beating jet lag: what really helps after long-haul flights

You land after a long flight, the sun is shining – and all your body wants is to sleep. Or you’re lying wide awake in your hotel bed at 3 a.m. Jet lag comes with long-haul travel, but you’re not helpless against it. On our trips to Asia, the Americas and Africa, the time difference is always something we have to deal with. Here’s what health authorities and sleep research say really helps.

What happens in your body when you have jet lag?

Your body has an internal clock that controls sleep, hunger, body temperature and hormones on a 24-hour cycle. It takes its cues mainly from daylight. When you fly quickly across several time zones, the clock outside suddenly no longer matches the one inside. Almost everyone knows the result:

• trouble falling asleep at night, or waking very early
• tiredness and drowsiness during the day
• poorer sleep quality
• problems with concentration and memory
• often an unsettled stomach as well

According to the NHS, symptoms usually improve within a few days as the body adjusts to the new time zone.

How long does jet lag last – and why is east worse?

A rough rule of thumb: about one day per time zone crossed. Fly from Germany to Bangkok (five to six hours’ difference depending on the season) and it can take almost a week until you’re fully back in rhythm. That’s an average, though – some people cope with time differences much better than others.

Direction makes a difference. Flying east shortens your day: you have to go to sleep earlier than your body is used to. Flying west lengthens the day, and you simply stay up a little longer. Because most people’s body clock runs slightly longer than 24 hours, stretching the day is easier than shortening it. That’s why flying to Asia feels harder for many people than flying to New York.

Direction	What happens	What matters
East (e.g. Asia)	The day gets shorter, you need to sleep earlier	Seek morning light, dim the lights in the evening
West (e.g. USA)	The day gets longer, you stay up later	Use afternoon and evening light, don’t go to bed too early
Short trip (2–3 days)	Adjusting is hardly worth it	Schedule appointments within your usual waking hours

Light: the most important lever

Light is the strongest cue for your body clock. The US Centers for Disease Control and Prevention (CDC) explains that deliberate exposure to light at the right time of day – and deliberately avoiding it at the wrong time – helps the body adapt to the new time zone.

• Flying east: Get outside in the morning. Bright morning light moves your body clock forward. In the evening, prefer dimmed light and less screen time.
• Flying west: Make use of late-afternoon and early-evening light, for example with a walk. That keeps you awake longer so you fall asleep on local time.
• For big time jumps (eight hours or more), bright light at the wrong time can even push your clock in the wrong direction. Jet lag calculators work out, for your specific flight, when to seek light and when to avoid it.

What can you do before you fly?

Adjusting doesn’t have to start at your destination:

• Shift your sleep schedule: A few days before departure, go to bed and get up a little earlier (heading east) or later (heading west), in small steps.
• Start well rested: Boarding the plane already exhausted makes things harder than they need to be.
• Choose your flight wisely: The CDC suggests choosing a flight that arrives at a time when you can make use of daylight straight away. Landing in the morning or early afternoon is often easier than arriving in the middle of the night.

How should you behave on the plane?

Set your watch to destination time when you board and follow it:

• If it’s night at your destination, try to sleep – with an eye mask, earplugs or noise-cancelling headphones.
• If it’s daytime there, try to stay awake: watch films, read, get up and walk a few steps.
• Drink enough water. Cabin air is dry.
• Go easy on alcohol and caffeine, especially in the hours when you want to sleep. Both disturb sleep.

The first days at your destination

• Switch to local time immediately: Eat, sleep and get up by the local clock – even when it’s hard.
• Short naps, not long siestas: Sleep for several hours during the day and you’ll be awake again at night. If you really can’t manage, keep it to a short power nap in the early afternoon.
• Move outdoors: A walk combines daylight and exercise – two of the best remedies for tiredness.
• Use caffeine strategically: A coffee in the morning can help you stay awake. Skip it from the afternoon onwards.
• Keep the first days relaxed: Don’t schedule important meetings or long drives on the day you arrive.

Tip: On your first day after a long-haul flight, plan a fixed outdoor goal – a park, a market or a walk on the beach. You’ll automatically get daylight and exercise and make it through to the evening.

What about melatonin and sleeping pills?

Melatonin is the hormone your body uses to signal night. How well it works against jet lag is assessed differently: the CDC refers to US sleep medicine guidelines that list timed melatonin as an option for frequent travellers. The UK’s NHS, on the other hand, does not recommend it because it considers the evidence insufficient.

For you, that means: don’t experiment with melatonin or sleeping pills on your own – talk to your doctor or pharmacist first, especially if you take other medication.

Short trip: is adjusting worth it?

If you’re only at your destination for two or three days, a full adjustment often isn’t worth it. The CDC notes that on short stays it can make sense to stay on home time and schedule appointments for the hours when you’re awake anyway. That spares you a second round of jet lag on the way home.

Our conclusion

You can’t avoid jet lag entirely, but you can make it much shorter. The most important adjustments cost nothing: light at the right time, a clear sleep schedule on local time, exercise and being mindful of caffeine and alcohol. If you’d like to arrive well rested, our article on upgrading to business class shows ways to get a lie-flat seat on long-haul flights.

For ideas for your next long-haul trip, read about a month in Bali and a week in New York, or browse our destinations and videos.