You land somewhere exciting after a long flight, ready to explore, and then it hits you. You are wide awake at three in the morning, dragging yourself through the afternoon, and hungry at all the wrong times. Jet lag can take the shine off the first days of a vacation and make a business trip feel like a blur, and the return home can be just as rough.
Jet lag cannot always be avoided entirely, but it can usually be made shorter and milder with a bit of planning. This guide lays out a simple plan for the days before you fly, the flight itself, and the first days after you arrive, built around how your body clock actually works. It is general information, not medical advice, so if you have a health condition, take regular medication, or are thinking about using sleep aids or supplements, talk to a doctor or pharmacist before your trip.
What jet lag is and why it happens
Your body runs on an internal clock, known as the circadian rhythm, that cycles roughly every 24 hours. It helps decide when you feel sleepy and alert, when you get hungry, and when various body processes speed up or slow down. This clock is kept in sync with the outside world mainly by light, and to a lesser degree by meals, activity, and social routines.
When you fly quickly across several time zones, the clock on your wall changes instantly, but your internal clock does not. For a while, your body still thinks it is in your home time zone. You might feel sleepy in the middle of the afternoon at your destination because, as far as your body is concerned, it is the middle of the night. That mismatch is jet lag.
Common symptoms include:
- Trouble falling asleep at night or waking up far too early
- Daytime sleepiness and low energy
- Difficulty concentrating
- Irritability or a low mood
- Upset stomach, changes in appetite, or irregular digestion
- A general sense of feeling “off” or unwell
The Centers for Disease Control and Prevention (CDC) notes that jet lag tends to be worse the more time zones you cross, and that it is often harder to adjust when traveling east than west. Flying east shortens your day and asks your body to fall asleep earlier than it wants to, which most people find tougher than staying up a little later.
East versus west: know which way you are shifting
Before planning anything, figure out which direction you need to move your body clock. This affects almost every step that follows.
- Flying east (for example, from the United States to Europe): You need to go to bed and wake up earlier than your body is used to. Morning light at your destination is your friend.
- Flying west (for example, from Europe to the United States, or from the US East Coast to Hawaii): You need to go to bed and wake up later. Afternoon and early evening light helps you stay up.
If you are crossing only one or two time zones, or staying somewhere for just a day or two, it may be easier to stay on your home schedule as much as possible rather than trying to adjust. For longer trips and bigger time differences, a deliberate plan pays off.
Before your flight: start shifting early
The days before departure are your best chance to give yourself a head start. You do not need to overhaul your life, but small changes add up.
Shift your sleep a little each day
For a few days before you leave, move your bedtime and wake time gradually toward your destination’s schedule. Heading east, go to bed and get up a bit earlier each day. Heading west, go to bed and get up a bit later. Even a partial shift means fewer hours of adjustment once you land.
Use light on purpose
Light is the strongest signal your body clock responds to. When shifting earlier for an eastbound trip, get bright light soon after you wake up and keep evenings dimmer. When shifting later for a westbound trip, seek out light in the evening and keep your mornings darker. A morning walk outdoors or an evening stroll can do more than you might expect.
Arrive well rested
Many travelers stay up late packing, then start the trip exhausted. Starting with a sleep debt makes jet lag worse. Pack a day or two early, plan your route to the airport, and give yourself a calm final evening. If you can, choose a flight that lets you arrive at a reasonable time of day for your plans.
Plan your first day at the destination
Think about how you will spend the first afternoon and evening after landing. A light schedule with outdoor time, an easy meal, and a sensible bedtime works better than either a packed agenda or an afternoon spent in a dark hotel room.
During your flight: set your watch and your habits
Once you board, start living on destination time as much as you reasonably can.
Switch to destination time immediately
Change the time on your watch and keep your phone set to update automatically. Then ask yourself what time it is at your destination. If it is nighttime there, try to rest. If it is daytime, try to stay awake, at least for most of the flight.
Sleep smart on overnight flights
An eye mask, earplugs or noise-canceling headphones, and a supportive neck pillow make sleeping on a plane far more realistic. Choosing a window seat means you will not be woken by neighbors who need to get up. Wear comfortable layers, since cabin temperatures can vary.
Drink water and go easy on alcohol and caffeine
Cabin air is dry, and feeling dehydrated can make you feel worse on arrival. Drink water regularly. Alcohol may seem to help you doze off, but it tends to lead to poorer quality sleep, and the CDC advises travelers to limit it. Caffeine can be useful for staying awake when it is daytime at your destination, but avoid it in the hours before you plan to sleep.
Move around
Get up and walk the aisle when it is safe to do so, and do simple seated stretches such as ankle circles and calf raises. Movement helps you feel less stiff, and health authorities, including the CDC and the World Health Organization (WHO), recommend it on long flights to support circulation. If you have a history of blood clots or other risk factors, ask your doctor about additional precautions before flying.
Time your meals
Try to eat according to destination mealtimes rather than whenever a tray appears. Some travelers find that skipping an in-flight meal served in the middle of their destination’s night, and eating a good breakfast after landing, helps reset their sense of timing. Lighter meals can also be easier on the stomach while flying.
After you arrive: the first three days
The first few days at your destination make the biggest difference. These are the habits that help your body clock catch up.
Get outside in daylight
Natural light is the most effective tool you have. After an eastbound flight, aim to get outdoors in the late morning and early afternoon, and be a little more cautious about very early morning light in the first day or two, since it can occasionally push your clock the wrong way. After a westbound flight, spend time outside in the afternoon and early evening. Even on a cloudy day, outdoor light is far brighter than indoor lighting.
Stay active, but keep it gentle
A walk around your new neighborhood, a visit to a park, or some light sightseeing helps you stay awake and gets you into the daylight. Save strenuous workouts and demanding activities for when you feel more adjusted.
Nap carefully, or not at all
When you are exhausted, a long afternoon nap is tempting, but it can make it much harder to sleep at night. If you truly need a nap, keep it short, set an alarm, and take it earlier in the afternoon rather than close to bedtime.
Eat on local time
Sit down to meals at local mealtimes, even if you are not especially hungry. Regular meals are another cue that helps your body settle into a new rhythm. A heavy meal right before bed may make sleep harder, so keep dinners reasonable.
Protect your first nights of sleep
Make your hotel room as sleep-friendly as possible: dark, quiet, and cool. Use the blackout curtains, an eye mask, or earplugs if needed. Put your phone away well before bed, or at least turn on its night mode, since bright screens can make it harder to wind down. If you wake up in the middle of the night, keep the lights low and try relaxing in bed rather than starting your day.
About melatonin and sleep aids
Melatonin is a hormone your body naturally makes in the evening to signal that it is time to sleep. Some travelers use melatonin supplements to help shift their body clock, and the CDC mentions it as an option that some people find helpful for jet lag. However, timing matters, products vary in strength and quality, and melatonin can interact with certain medications.
Prescription and over-the-counter sleep medications carry their own risks, including next-day grogginess and interactions with alcohol. Because of this, it is wise to talk with a doctor or pharmacist before using any sleep aid or supplement, especially for the first time or alongside other medicines. Never take a new sleep medication for the first time on a flight.
Coming home: the return trip counts too
Many people plan carefully for the outbound journey and then forget that the trip home shifts their body clock in the opposite direction. The same principles apply in reverse.
- In the last day or two of your trip, start nudging your sleep times toward your home schedule if your plans allow.
- On the flight home, switch to home time as soon as you board.
- Get daylight at the right times once you are back, and avoid long naps.
- If possible, give yourself a buffer day before returning to work or school, so you are not facing important tasks while still adjusting.
A sample plan at a glance
| When | Flying east | Flying west |
|---|---|---|
| Few days before | Go to bed and wake earlier; get morning light | Go to bed and wake later; get evening light |
| On the plane | Set watch to destination time; sleep if it is night there | Set watch to destination time; stay awake if it is day there |
| Arrival day | Late morning and midday light; early but reasonable bedtime | Afternoon and evening light; stay up until a normal local bedtime |
| Next few days | Local meals, short naps only, consistent wake time | Local meals, short naps only, consistent wake time |
Common mistakes to avoid
- Taking a long nap the afternoon you arrive. It feels wonderful in the moment but often leads to a sleepless night.
- Relying on alcohol to sleep on the plane. It tends to reduce sleep quality and can add to dehydration.
- Drinking coffee late in the day to push through, then wondering why you cannot fall asleep.
- Staying indoors in a dim room instead of getting the daylight your body clock needs.
- Scheduling something important on arrival day, such as a key meeting or a long drive, when you are likely to be tired. Drowsy driving is dangerous, so consider a shuttle, taxi, or train on arrival.
- Ignoring the trip home and walking straight back into a full schedule.
Frequently asked questions
How long does jet lag usually last?
It varies from person to person and depends on how many time zones you crossed and in which direction. A common rule of thumb is that the body adjusts by roughly one time zone per day, though some people adjust faster and others more slowly. Using light, meals, and sleep timing wisely can shorten the adjustment.
Is it better to stay up all night before a long flight?
Generally, no. Starting a trip sleep-deprived usually makes you feel worse and does not reliably help you adjust. You are better off arriving reasonably rested and using the strategies above to shift your schedule.
Do children get jet lag too?
Yes, children can experience jet lag as well. The same principles of daylight, local mealtimes, and consistent routines apply, and keeping familiar bedtime rituals can help young travelers settle. Ask a pediatrician before giving children any supplement or sleep aid.
Should I adjust for a very short trip?
For trips of just two or three days, many travelers find it easier to stay close to their home schedule, planning important activities for times when they would normally feel alert. For longer stays, adjusting to local time is usually worth the effort.
The bottom line
Jet lag happens because your body clock cannot jump time zones as fast as an airplane can. Start shifting a few days before you leave, switch to destination time the moment you board, get daylight at the right times, eat on the local schedule, and resist long naps. With a simple plan in place, you will spend less of your trip feeling foggy and more of it enjoying where you are.