How to Recover from Jet Lag: A Time-Zone Reset Plan

Why one day per zone, and why east is worse

Your body runs on a circadian clock set to roughly 24 hours and anchored by light. When you jump several time zones, that internal clock still points to where you left, and it only drifts back into step slowly — about one zone per day for most people. Cross three zones and you are groggy for a few days; cross eight and the reset stretches over a week.

Direction matters because of how the clock likes to move. Flying west lengthens your day: you stay up later, which fits the body's natural tendency to drift a little longer than 24 hours. Flying east shortens your day and forces the clock earlier, working against that tendency. That is why eastbound jet lag typically hits harder and takes longer to shake, even over the same number of zones.

Use light as the master switch

Light is the strongest signal your clock reads, so timing it well is the fastest lever. After flying east, seek bright morning light and avoid it in the late evening — this pulls your clock earlier to match the new, shorter day. After flying west, do the opposite: get light in the evening and shield your eyes from early-morning brightness, which pushes your clock later.

Because the timing depends on your specific flight, a jet-lag tool that knows your departure, arrival and direction can tell you the exact hours to seek and avoid light. Pair light with consistent meal times on the local clock, and keep screens dim near your new bedtime, since bright blue light late can undo the morning's work.

Sleep, meals and small helpers

Adopt the destination's schedule the moment you land. Eat at local mealtimes even if you are not hungry, and try to stay awake until a normal local bedtime so your first full sleep aligns with the new night. If you must nap, keep it under 30 minutes so it takes the edge off fatigue without stealing from night sleep.

Melatonin, taken in a small dose timed to the new night, can nudge the clock and is widely used for eastward trips; check local rules and any medication interactions first. Stay hydrated, since cabin air is dry, and go easy on alcohol and late caffeine, both of which fragment sleep. None of these is a cure — they simply help your one-day-per-zone reset arrive a little sooner.

Frequently asked questions

How long does jet lag last?

Roughly one day per time zone crossed. Cross four zones and expect about four days to feel normal; cross eight and it can take a week or more. Eastward trips usually take longer to recover from than westward ones.

Is jet lag worse flying east or west?

East is usually harder. Flying east shortens your day and asks your clock to advance, which the body resists, while flying west lengthens the day and lets you stay up later — a shift the clock accepts more easily.

Does melatonin help with jet lag?

It can, especially for eastward travel, when a small dose is timed to the destination's night to shift the clock. It is not a sedative and does not work instantly. Check local regulations and any medication interactions before using it.

Should I nap when I arrive?

A short nap is fine, but keep it under 30 minutes and take it early in the day. Long or late naps steal from your night sleep and slow the reset. The goal is to stay awake until a normal local bedtime.