What's the most effective way to reset my sleep schedule after jet lag or shift work?

Jet lag recovery is accelerated by three timed interventions used together: (1) melatonin at 0.5–1 mg taken at destination bedtime starting the day of travel, (2) morning sunlight exposure at destination local time (even if you feel like sleeping in), and (3) eating meals at destination local meal times from day 1, meal timing is a secondary circadian entrainment signal operating through peripheral clock genes in the liver and gut (Herxheimer & Petrie, Cochrane Database, 2002).

Shift work sleep disorder (persistent circadian misalignment from rotating shifts) is more complex and requires a consistent shift schedule, blackout curtains for daytime sleep, and melatonin timed to the desired sleep window of that shift. The fastest circadian reset is light-based: exposing yourself to bright light at the time you want to be awake advances or delays the clock depending on when light is received relative to your current nadir (the "phase response curve"). Getting these timing right matters, bright light at 2 AM delays your clock; bright light at 7 AM advances it.

Honesty Scale: Solid (1) for melatonin + light exposure for jet lag. Solid (1) for meal timing as a secondary circadian signal.

What to do: For eastward travel (clock advance needed): take melatonin at 10 PM destination time, bright light exposure in destination morning. For westward travel (clock delay): evening light exposure at destination, melatonin on arrival if needed for acute sleep initiation. Do not black out morning light for eastward adjustment, it will extend your jet lag.

For the full picture, read The Sleep Hygiene Deep Dive