How many days before Tokyo should I shift my sleep when flying from New York?

    Start 3 days before you fly New York → Tokyo, moving sleep about one hour later per day. That leaves about 5 days of adjustment on arrival instead of 8 days.

    Flight time
    13h 7m to 14h 45m
    10,875 km
    Body-clock shift
    11 hours
    westward
    To adjust
    8 days
    severe jet lag

    Why, for this route

    • Direction: 11 hours westward. Delaying is easier, so even one evening of late light helps.
    • Shift light, not just bedtime — light timing is what moves the clock; the alarm only follows.
    • Do not pre-shift more than about 3 days: the gain flattens and the disruption at home starts to cost more than it saves.
    • On arrival, Day 1 in Tokyo: bright light 17:00–19:00, last caffeine 16:00, sleep 00:00–08:00.

    Your pre-departure schedule

    1. 3 days before departure
      Sleep and wake 1 hour later than usual, and take your bright light in the late evening.
    2. 2 days before departure
      Sleep and wake 2 hours later than usual, and take your bright light in the late evening.
    3. 1 day before departure
      Sleep and wake 3 hours later than usual, and take your bright light in the late evening.

    Day 1 in Tokyo

    • 17:00–19:00Seek bright light
    • 16:00Last caffeine
    • 00:00–08:00Target sleep window

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    Evidence-based recommendations

    Each recommendation below is graded by how strongly published research supports it, with the source it comes from. Optimal timing depends on your travel direction, the number of time zones crossed and your own circadian phase, so treat the schedule as a starting point.

    • Seek evening light

      Strong

      Bright light in the local evening helps delay your body clock when travelling west.

      CDC Yellow Book 2026

    • Limit light in the early morning

      Strong

      Early light can advance your clock and work against a westward shift during the first days.

      NIH — Circadian rhythms

    • Shift bedtime later before departure

      Moderate

      Moving sleep and wake times 30-60 minutes later for a few nights gives your clock a head start on a westward trip.

      CDC Yellow Book 2026

    • Live on destination time on arrival

      Moderate

      Sleeping, eating and being active on local time gives your body consistent cues about the new day.

      CDC Yellow Book 2026

    • Consider timed melatonin

      Moderate

      Low-dose melatonin near the local bedtime can help with sleep timing after crossing several zones; timing matters more than dose.

      Cochrane review — Melatonin for jet lag

    • Use caffeine early, not late

      Practical advice

      Caffeine can help you stay awake during local daytime, but late doses tend to delay sleep onset.

      CDC Yellow Book 2026

    • Protect sleep around the flight

      Practical advice

      Arriving without a large sleep debt makes the first days easier, even when few time zones are involved.

      CDC Yellow Book 2026

    How we grade evidence

    Strong
    Consistently supported by controlled circadian research and current public-health guidance.
    Moderate
    Supported by research, but effect size and best timing vary between individuals and studies.
    Practical advice
    Sensible travel habits with limited direct evidence for shifting the body clock.

    This is general travel information, not medical advice. Talk to a clinician before using melatonin or sleep medication, especially if you are pregnant, take other medication or have a sleep disorder.

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