Jet lag happens when fast travel across time zones desynchronizes your internal circadian clock from the local day-night cycle, leading to fatigue, poor sleep, and reduced concentration.

How long does jet lag last?

As a rule of thumb your circadian rhythm shifts roughly one hour per day, so a six-hour time change typically takes several days to fully adjust. Eastward travel is usually harder than westward.

Can a planner actually reduce jet lag?

Yes. A structured plan that times sleep, light exposure, and activity in the days before and after a flight can meaningfully shorten adjustment compared with doing nothing.

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Jet Zzz Blog — Practical Jet Lag Guides

Jet Zzz BlogPractical jet-lag guides written from first-hand travel.

How to Beat Jet Lag from the US to Japan: A Complete Guide

Melatonin for Jet Lag: Dosage, Timing, and Common Mistakes

Westbound vs Eastbound Jet Lag: Why Direction Matters