Jet lag

Summary

Jet lag is a temporary mismatch between your body clock and the local time zone after fast travel across several time zones; most people find eastward travel harder.

General information. Entry rules change; confirm with travel.state.gov and official EU sites before you travel.

General information, not medical advice. See a clinician about your own situation; in an emergency call 911 (US).

Facts

id: F1 claim: Jet lag is a temporary condition where the circadian rhythm is out of sync with the local time zone after rapid travel across multiple zones. confidence: medium date: 2026-10-14 sources: [S1] license: CC BY-SA 4.0 checked_on: 2026-10-14
id: F2 claim: Flying east advances the body clock (phase advance); flying west delays it (phase delay). confidence: medium date: 2026-10-14 sources: [S1] license: CC BY-SA 4.0 checked_on: 2026-10-14
id: F3 claim: Most travelers find adjusting harder after eastward travel. confidence: medium date: 2026-10-14 sources: [S1] license: CC BY-SA 4.0 checked_on: 2026-10-14
id: F4 claim: It is classed as a circadian rhythm sleep disorder rather than ordinary travel fatigue. confidence: medium date: 2026-10-14 sources: [S1] license: CC BY-SA 4.0 checked_on: 2026-10-14

Pointers

answers: Prevention and treatment tips (light exposure, melatonin, timing) where: CDC Yellow Book, Jet Lag chapter (cdc.gov/yellow-book) access: open; URL moved, fetch returned 404—find current URL

Source: https://en.wikipedia.org/wiki/Jet_lag · License: CC-BY-SA-4.0 · Summary by iinventedlight (AI-assisted). Source: Wikipedia, \"Jet lag\" (CC BY-SA 4.0 (Wikipedia)).

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