Most advice explains why jet lag happens. This is a practical guide on what to actually do to beat jet lag, and when to do it.
Jet lag can make or break a long-distance trip. Shifting time zones can be hard to get your head around, leaving you feeling truly scrambled when you arrive at your destination. If you’re only visiting for a week, you can lose vital days, just trying to recover. It can be dangerous too. I met a friend for drinks on arrival in Bangkok, and was alone in an unfamiliar city at night when the jet lag kicked in. I was confused, lost, and disorientated, not entirely clear on how to get back to my accommodation.
Jet lag can feel unpredictable and a matter of chance, but it responds well to timing, and badly to guessing. The advice below is specifically about when to act, since getting the things backwards can make jet lag worse rather than better.
Start Adjusting 3 to 5 Days Before You Fly
Traveling east, shift your bedtime roughly 30 minutes earlier each night for three or four nights before departure. Traveling west, do the opposite and stay up a little later each night. Shift your meals toward your destination’s schedule over the same period — your body responds to eating times almost as strongly as it does to light. Neither adjustment is dramatic on any single day, but three or four days of it compounds into a meaningful head start on the crossing.
Time Your Light Exposure
This Is the Part Most People Get Backwards. For eastward trips of three to six time zones, get bright light in the morning on the day before and the day of departure, which helps shift your body clock forward. For westward travel, seek out bright light in the evening instead. Getting light at the wrong time of day can push your adjustment in the wrong direction, so this isn’t a “more light is always better” situation.
If you want precision, the Timeshifter app builds a personalised light-exposure and sleep schedule based on your exact flights and sleep pattern. It’s used by professional athletes and shift workers for major time-zone changes and is worth the cost for a crossing of eight or more hours.
On the Plane: Switch to Destination Time the Moment You Board
Set your watch, phone, and mental clock to your destination’s time zone as soon as you’re seated, not when you land. Eat lightly or skip a meal if it falls at an odd hour for your destination, and only sleep if it would be nighttime where you’re headed. Forcing wakefulness or sleep against your destination’s clock undoes the adjustment you started before the flight.
Avoid alcohol on the flight. It may help you fall asleep initially, but it messes with sleep quality and lengthens the adjustment period.
Approach caffeine the same way. It is useful for keeping yourself awake to match destination time, but counterproductive if taken within four to six hours of when you’re trying to sleep. Staying well-hydrated throughout the flight reduces fatigue on landing and makes the adjustment easier: cabin air is drier than most deserts, and dehydration compounds everything.
Melatonin: When and How Much
A small dose of melatonin — 0.5 to 5mg — taken at your destination’s bedtime, not your body’s, helps signal the shift.
Lower doses (0.5 to 1mg) work as well for many people as the higher doses common in US supplements and carry fewer side effects; the 5mg and 10mg tablets widely sold in pharmacies are often more than necessary.
Take it 30 to 60 minutes before your intended sleep time at the destination. It works best as a “starting tonight” tool once you’ve landed, not as something to take pre-emptively for days before you fly.
Your First Evening: Stay Awake Until Local Bedtime
This is the hardest part of jet lag management and also one of the most effective. If you land in the afternoon local time, resist the urge to nap in your hotel. A very short rest of 20 minutes is fine if you genuinely cannot keep your eyes open; anything longer locks in the wrong time zone for days. Aim to stay awake until 9 or 10pm local time on your first night, then sleep through until morning. One proper night’s sleep at local time resets your clock faster than almost anything else.
Your First Morning There Matters Most
Spend at least 45 minutes outdoors in natural light on your first morning at your destination, ideally without sunglasses. This single window does more for resetting your circadian rhythm than almost anything else on this list. Light physical activity — a brisk walk, a run — compounds the effect: your body responds to both light exposure and movement as cues that it’s morning and that your clock should set itself to this location, not home. A morning walk that doubles as light exploration of wherever you’ve landed is one of the more pleasant aspects of long-haul travel when it works as intended.
Caffeine: Use It Deliberately
Once you’ve landed, caffeine is a legitimate tool for extending wakefulness into the evening on your first day. Drink a coffee or tea in the early afternoon if that’s what it takes to get through to local bedtime. Avoid caffeine after 2pm local time (or earlier if you’re sensitive to it), since it has a half-life of five to six hours and can prevent you from falling asleep at local bedtime, which is exactly the outcome you’re trying to avoid. Morning coffee on a normal schedule is fine and may help reinforce the morning signal alongside light exposure.
Short Trips: Sometimes Don’t Bother
For trips of three days or fewer — a long weekend across a few time zones or a two-day work trip — full circadian adjustment may not be worth attempting. Your body won’t fully adapt in that time regardless, and the effort of trying can leave you more disoriented than simply staying mostly on home time and managing fatigue deliberately with sleep timing and caffeine. Reserve the full adjustment protocol for stays of a week or longer where it will actually pay off.
✈️ Find Flights
Use Skyscanner to compare fares across airlines and dates. Booking around three months ahead generally gives the best prices on most routes; flexibility on dates can reduce the fare further.
The Short Version
Shift your sleep and meals a few days before you fly, get light exposure at the correct time rather than just more of it, switch to destination time the moment you board, avoid alcohol and mis-timed caffeine on the plane, stay hydrated, take low-dose melatonin at destination bedtime, force yourself through to local bedtime on your first night, and get outside in natural light on your first morning. Skipping the timing details is usually what separates people who adjust in a day from people who take a week.
