Jet Lag: A Practical Recovery Plan

Jet lag is not "tiredness from flying" — it is a temporary mismatch between your internal circadian clock and the local time at your destination. The body adjusts about 1 time zone per day eastward and 1.5 zones per day westward, so a New York → London trip naturally takes 5 days to resolve. With the right pre-trip plan and light strategy, you can cut that in half.

Eastbound vs. westbound — why direction matters

The human circadian system naturally runs slightly longer than 24 hours, which makes westbound travel (delaying your schedule) much easier than eastbound (advancing it). Eastbound flights force you to fall asleep before your brain is biologically ready, and the resulting "phase advance" is the hardest adjustment in chronobiology.

Three days before you fly

• Eastbound: Shift bedtime and wake time 1 hour earlier each night for 3 nights. Get bright light immediately upon waking.
• Westbound: Shift bedtime 1 hour later each night. Stay up under bright light; sleep in the next morning.
• Use the sleep calculator to find cycle-aligned bedtimes for your new target time.

On the plane

• Set your watch to destination time the moment you board. Eat and sleep on the new schedule from that point.
• Skip alcohol — it fragments REM and worsens dehydration, both of which extend jet lag.
• Cap caffeine at one cup, more than 8 hours before your target destination bedtime.
• If your destination time is "night" during the flight, use eye mask + earplugs + a 90-minute sleep block (one full cycle).

The light strategy at your destination

Light is by far the most powerful zeitgeber (clock-setter). Getting it at the wrong time can make jet lag worse. As a simple rule:

• Flew east (e.g. US → Europe): Seek bright outdoor light in the destination morning. Avoid bright light in the early morning of the first 1–2 days if you woke before 5 AM local — this is your body's "biological night" and light there pushes the clock the wrong way.
• Flew west (e.g. Europe → US): Seek bright light in the destination evening. Avoid bright morning light for the first day if you wake unusually early.

Melatonin: dose, timing, and what to expect

The Cochrane review found 0.5–5 mg of melatonin taken at destination bedtime for the first 4–5 nights modestly speeds adjustment, especially eastbound across 5+ time zones. Lower doses (0.3–0.5 mg) match natural physiologic levels and are usually enough. Higher doses can cause morning grogginess.

Melatonin is a clock-setter, not a sedative. If you cannot fall asleep, the issue is usually light exposure, not dose. Pair melatonin with a dark, cool room and a calming routine.

A sample 5-day plan: New York → London (5 hours east)

1. Days −3 to −1 (NY): Bedtime 1 hr earlier each night. Bright light at wake.
2. Travel day: Set watch to London time at boarding. Sleep block in last 3–4 hrs of flight. No alcohol.
3. Day 1 (London): 30+ min outdoor light between 8–11 AM. Light walk after lunch. 0.5 mg melatonin at 10 PM. Bed at 11 PM.
4. Days 2–3: Same morning-light pattern. Permit one 20-minute nap before 2 PM if needed.
5. Day 4: Drop melatonin. Maintain consistent wake time.

Westbound is easier, but don't overdo it

For Europe → US, the temptation is to nap immediately on arrival. Resist. A 20-minute nap is fine; a 3-hour nap will trap you in a multi-day cycle of late nights and afternoon crashes. Stay outdoors in the destination afternoon and aim for a bedtime around 10:30 PM local on night 1.

What to tell yourself when it's still rough

Even with perfect technique, eastbound trips across 6+ zones often produce one bad night around day 2 — a "circadian whiplash" night when your body is roughly halfway shifted. Expect it. A short walk in evening light, a warm shower, and a 4-7-8 breathing round can shorten the wake. Read our breathing exercises guide.

The one-line summary

Pre-shift your schedule, set your watch on boarding, chase light at the destination, use low-dose melatonin at destination bedtime, and accept one rough night around day 2.