Jet lag is not just tiredness. It's a form of circadian misalignment — your body's internal clock is still set to your home time zone while the external world around you is running on a different schedule. Virtually every physiological process — sleep, digestion, hormone secretion, cognitive performance — becomes temporarily desynchronized.
Why Eastward Travel Is Harder
Flying east forces your body to advance its clock — to sleep and wake earlier relative to your home rhythm. Humans find this harder than westward travel (phase delay) because our natural circadian period is slightly longer than 24 hours, making it naturally easier to stay up later than to go to bed earlier. Eastward travelers typically need 1–1.5 days of recovery per time zone crossed; westward is slightly faster.
The Recovery Toolkit
Effective jet lag recovery uses three levers:
- Light timing — Getting light at the right local time is the most powerful way to shift your clock.
- Melatonin — Low-dose melatonin (0.5–1 mg) taken at the target bedtime helps phase-shift your clock.
- Sleep anchoring — Committing to local sleep/wake times immediately on arrival, even if it's difficult, accelerates adaptation.