Jet lag: how long it lasts and how to get over it

You land after a long flight, and by mid-afternoon you could fall asleep standing up. Then at 2am you're wide awake. That's jet lag, and from Australia, almost every overseas holiday crosses enough time zones to bring it on.

Here is why it happens, how long it usually lasts, and simple ways to settle in faster, plus how the Thrive Health Band and the Thrive by Optihealth app can show you when your body has caught up.

What is jet lag?

Your body runs on an internal clock, your circadian rhythm, which tells you when to feel sleepy, hungry and awake across roughly 24 hours. Daylight is its strongest cue.

When you fly quickly across several time zones, that clock is still running on home time while the sun and the local clocks say something else. Until the two line up again, you can feel out of step.

Jet lag can show up as:

feeling very tired during the day
trouble falling asleep, or waking in the middle of the night
foggy concentration and a shorter fuse
a different appetite and an unsettled stomach
generally feeling a bit off

It's different from travel tiredness from the flight itself, which usually lifts after a good night or two.

How long does jet lag last?

Healthdirect says adjusting to a new time zone usually takes at least two or three days. A common rule of thumb from Better Health Channel is roughly one day for each hour of time difference, so a big shift can take a week or more to settle fully.

How long yours lasts depends on:

How many time zones you cross. Brisbane to London is around nine or ten hours; Sydney to Bali is two or three.
Which direction you fly. Flying east tends to feel harder than flying west.
Your age. Body clocks can adjust more slowly as we get older.
How you slept before you left. Starting the trip already short on sleep makes it harder.

Why flying east feels harder

Your body clock finds it easier to stretch a day than to shorten it. Flying west, as you do from Australia to Europe, gives you a longer day, so you are mostly staying up later. Flying east, as you do to the west coast of the US, means trying to fall asleep earlier than your body expects, which is tougher.

That's why the trip home can feel different from the trip out.

How to get over jet lag faster

You can't avoid jet lag completely, but you can help your body clock catch up.

Shift your sleep before you go. For a few nights, move bedtime 30 to 60 minutes towards your destination's time.
Switch to local time on the plane. Set your watch to destination time, and try to sleep and eat as you would there.
Drink water and go easy on alcohol and caffeine in the air. Being dehydrated can make you feel worse.
Get daylight at the right time. After flying east, get morning light. After flying west, get afternoon and evening light. Keep the room dark at night.
Keep naps short. Healthdirect suggests no more than 30 minutes, and staying awake for at least four hours before bed.
Eat on local time. Regular meals at local times give your body clock another cue.
Move during the day. A walk outside combines light and activity.

For a short trip of a few days, it can make more sense to stay close to home time for sleep and meals. If you take regular medicines, talk to your GP before you go about timing them across time zones. And if you are thinking about melatonin or any sleep medicine, talk to your GP or pharmacist first.

Getting back on track at home

Coming home is a second round of jet lag, often while you're also back at work. Give yourself an easy first day if you can, get outside in the morning, and keep your wake time steady even if the first nights are broken. The morning sunlight and circadian rhythm article explains why morning light helps.

See when your body has caught up with Thrive

The Thrive Health Band has no screen, so it's comfortable to sleep in on a plane or in a hotel, and up to 14 days of battery means a shorter trip may not need the charger at all. Overnight it tracks sleep, resting heart rate, HRV and temperature.

Thrive learns what is usual for you right across your health, from sleep, heart and activity to mood, energy, stress, meals, medications and more. After a long flight, you can see how far your sleep and overnight heart rate have moved from your own normal, and watch them settle back day by day. Sleep detail shows your time asleep and stages each night, and naps appear in their own Nap card, so you can see if a "quick nap" turned into two hours.

Tag Travel in your Daily Check-In on travel days. Your Today's Vitality score may sit lower than usual for a few days after a big trip; that's information, not a judgement. Thrive also gives recovery insights, including how much rest you may need to get back to baseline.

In settings, the Bedtime Reminder can use a bedtime from your sleep pattern or one you set yourself, which is handy when you're shifting to a new time zone. Then ask Ask Thrive questions such as:

"How long did my sleep take to settle after my last trip?"
"Is my resting heart rate back to my usual range yet?"
"Do I sleep better after travel when I skip alcohol on the flight?"

If you'd like someone else to keep an eye on how you're going, Thrive Loops lets you share selected information with a participating trainer, health professional or someone you trust. You decide what to share and with whom, and you can change or revoke access at any time.

When to talk to your GP

Jet lag usually fades on its own. If you're still sleeping badly or feeling very tired weeks after you get home, or you travel so often it keeps knocking you around, book in with your GP. Thrive isn't a diagnosis, but your sleep trends and history are right there in the app, and Ask Thrive can help you pull together what has changed and when.

Before you buy

You'll need a compatible iPhone or Android phone, because the Thrive app is on the Apple App Store and Google Play, in Australia and eight other countries. The app stores are only for downloading the app, though; they aren't where you buy the Band or a Plan. You can buy at thrivehealthband.com, or at a participating World Gym Australia location or health and wellness clinic.

The Thrive Health Band is A$660 for the first year under the launch offer. That includes the Band, which is yours to keep, and 12 months of the Thrive by Optihealth app, My Health on the web, Health Fingerprint, Ask Thrive, Thrive Loops and your data, paid once upfront. Prices are in AUD and include GST. Free Australia-wide shipping during the launch offer (usually A$14.99).

Nothing renews automatically. After your first year, you can get a new band plus 12 more months for A$660, or keep your band and renew the Thrive Connected Plan for A$240 a year, or A$29 a month with no lock-in.

You're also covered by a 12-month Thrive Care Warranty, and consumer guarantees under Australian Consumer Law always apply. See Returns if something is wrong with your purchase.

Common questions

Is jet lag worse flying to Europe or America from Australia?

Europe usually means more time zones, but flying west. America means fewer time zones, but flying east, which tends to feel harder. Both can take several days.

Should I sleep when I arrive in the morning?

Try to stay up until a normal local bedtime, with a short nap of up to 30 minutes if you need it.

Can I wear the Thrive Band on a plane?

Yes. It has no screen, so you can wear it on the flight and to bed when you land.

For more answers, see Questions.