Jet lag: tips to recover quickly after long‑haul flights

Jet lag is a temporary circadian‑rhythm disorder that occurs when travelers cross multiple time zones. The body typically needs about one day to adjust for each zone crossed, and eastward flights are usually more disruptive because they shorten the day. Common symptoms include daytime fatigue, nighttime alertness, reduced concentration, headache and mild gastrointestinal upset.

Experts advise starting the adjustment before departure: for eastward travel, go to bed and rise an hour earlier each day; for westward travel, shift the schedule later. After arrival, exposure to daylight at the appropriate local times, avoiding caffeine and alcohol, and using melatonin supplements at the target bedtime can help reset the internal clock. Munich chronobiologist Till Roenneberg coined the term “social jet lag,” and a Northwestern University study found professional football players lose more games after eastward trips. The International Classification of Sleep Disorders (ICSD‑3) lists jet lag as a distinct circadian‑rhythm disorder. NASA uses programmed LED lighting on the ISS to mitigate rhythm disruptions for astronauts.