Getting Over Jet Lag Faster

Jet lag happens when your body clock is still running on home time while your watch says something else. The master clock in the brain, which times sleep, hunger, alertness and digestion, can only shift gradually, by roughly an hour or so a day on its own. Crossing six time zones can therefore leave you out of step for most of a week. You can't skip the adjustment, but you can help the clock move faster and in the right direction.

The most powerful signal to that clock is light. Light in the morning, by your body's reckoning, shifts the clock earlier. Light in the evening shifts it later. Most of the practical advice comes down to seeking and avoiding light at the right times.

Why direction matters

Flying east, for example from New York to Paris, means your day becomes shorter and you need to fall asleep earlier than your body wants to. Flying west, say from London to Los Angeles, lengthens your day, which most people find easier, since staying up a little late comes more naturally than going to bed early. Many travelers notice that eastward trips take longer to recover from.

In the days before you leave

If you can, start shifting a little before you go. For an eastward trip, go to bed and get up an hour earlier each day for two or three days, and get bright light soon after waking. For a westward trip, do the opposite: stay up an hour later and sleep in. Even a partial shift reduces the gap you face on arrival.

Arrive as rested as possible. Starting a long trip already short on sleep makes everything harder.

On the plane

Set your watch to destination time when you board and try to eat and sleep accordingly. If it is night at your destination, use an eye mask and earplugs and try to sleep. If it is daytime there, try to stay awake, keep the window shade up and move around the cabin. Drink water regularly, since cabin air is dry, and go easy on alcohol, which fragments sleep, and on caffeine late in the flight.

Arrival day

Fit into the local schedule straight away. Eat meals at local times, even small ones. Get outside in daylight, which is far brighter than indoor lighting even on a cloudy day.

After a long eastward flight, timing matters. If you have crossed many time zones, bright morning light at your destination can fall at the wrong point of your body clock and push it the wrong way. A common recommendation after crossing eight or more zones eastward is to avoid bright light for the first few hours of the morning, for example with sunglasses, and seek it from late morning on. Free online jet lag planners, and apps based on published circadian research, can calculate personal light schedules for a specific trip.

If you must nap, keep it to 20 to 30 minutes and before mid-afternoon, so it doesn't steal the night's sleep.

The first few days

Keep going to bed and getting up at local times, even if you wake in the night. Exercise outdoors in daylight helps both light exposure and sleep. Expect some tiredness and poor concentration, and if you can, avoid scheduling the most important meeting or event for the first day after a long eastward flight.

Caffeine and meals

Caffeine can help you stay alert through a long first afternoon, but its effects last for hours, so stop several hours before your intended bedtime at the destination. Meal timing also nudges the body clock, especially the clocks in the gut and liver. Eating breakfast at local breakfast time, even if you are not hungry, and avoiding large meals in the middle of the local night helps the rest of the body follow along.

Traveling with children

Children often adjust a little faster than adults, but they show tiredness in different ways, with meltdowns and early waking more common than yawning. The same principles apply: daylight outdoors in the morning, meals at local times and a consistent bedtime routine. Keeping a familiar comforter, blanket or bedtime story helps signal sleep in an unfamiliar room.

Melatonin

Melatonin is the hormone the body produces in the evening as darkness falls. Taken as a supplement, it has reasonable evidence for reducing jet lag, especially after eastward flights across several time zones. Low doses, often 0.5 to 3 milligrams, taken around local bedtime for a few nights tend to be used. In the US it is sold as a dietary supplement, so product strength can vary from the label. Check with a doctor first if you take other medicines, are pregnant, or have a health condition.

Short trips

For a trip of two or three days, it may make more sense to stay on home time as far as possible, scheduling important events when you would naturally be alert, rather than shifting your clock only to shift it back again.