Jet Lag and circadian rhythm: fixing bed and rise times when adapting

The first time I really noticed jet lag wasn’t on the long-haul flight itself—it was two mornings later when my alarm rang and my body politely declined. My brain felt like it had stayed behind at the departure gate. That morning I scribbled a note to myself: if the plane can cross time zones in half a day, why does my body take several more to catch up? Since then I’ve been quietly experimenting with a simple, humane idea: use bed and rise times as anchors, and nudge them with light, timing, and tiny habits until my internal clock cooperates. This post is me thinking out loud—part travel diary, part evidence-informed playbook—about how I now adjust bedtime and wake time when I cross the world.

Why my body clock lagged while my flight didn’t

Jet lag happens because my internal clock (the circadian system) keeps “home time” for a while even after my watch says otherwise. The master pacemaker in the brain (the suprachiasmatic nucleus) responds mainly to light, and more gently to behavioral cues like sleep timing, meals, and activity. It can’t jump instantly; it shifts by increments—think of it like turning a giant ship, not snapping a skateboard. The exact pace depends on direction (east is usually harder than west), number of time zones, and how consistently I send the right signals. The good news is that two levers—exposure to light and the timing of sleep—do most of the heavy lifting if I plan them on purpose.

  • Eastward travel usually needs a phase advance: earlier light and earlier sleep/wake times.
  • Westward travel usually needs a phase delay: later light and later sleep/wake times.
  • Most people can shift about 1–2 hours per day comfortably; pushing faster feels rough and creates “social jet lag.”

For a plain-English overview of why this lag happens and how travelers can plan realistically, I’ve found the CDC’s Yellow Book chapter on jet lag reassuring and practical—especially the emphasis on light timing and gradual schedule shifts. Here’s the reference I bookmarked early on: CDC Yellow Book Jet Lag (2024).

The two levers I actually control most days

When I’m tired and foggy, complicated plans don’t stick. So I reduce it to two levers and a few supportive habits. The two levers:

  • Light timing: Bright light in the new morning tends to advance the clock; bright light in the new late evening tends to delay it. Avoiding the wrong light at the wrong time matters as much as seeking the right light.
  • Bed and rise anchors: I pick a target bedtime and wake time for the destination, then “walk” my current times toward them by 60–120 minutes per day. The anchors don’t have to be perfect as long as they’re steady.

Supportive habits that gently reinforce the shift:

  • Meal timing: Move breakfast toward the destination morning, dinner toward the destination evening. I try not to graze at 2:00 a.m. local time unless I really need a small snack to sleep.
  • Movement: A short, brisk walk soon after local sunrise is a low-friction way to get natural light and wakeful cues together.
  • Caffeine: I keep it modest and time it for destination morning/early afternoon to boost alertness without sabotaging the new bedtime.
  • Melatonin (optional): Some travelers find a low-dose supplement helpful for timing the sleep signal. I keep expectations modest and check reliable guidance; the NIH Office of Dietary Supplements summary is a good place to start if you’re curious.

A simple framework I use before and after landing

Here’s the planning template I keep in my notes app. It’s not magic, just consistent. I don’t expect perfect nights—only a steady drift toward the goal.

  • Step 1: Decide the target anchors. I choose a realistic destination bedtime and wake time (for work trips, sometimes I pick “anchor sleep,” e.g., 5 hours between 2:00–7:00 a.m. local, and stretch toward 7–8 hours later).
  • Step 2: Map the gap. Count the time difference and direction. East is advance; west is delay.
  • Step 3: Make a 3–5 day schedule. Shift bed and rise times 60–120 minutes per day toward the target. Add light: seek bright morning light when advancing; seek bright late-evening light when delaying; wear sunglasses or minimize light during the opposite window.
  • Step 4: Add gentle guardrails. Cap naps at ~20–30 minutes before midafternoon. Keep caffeine mostly to local mornings. Time meals with the day you’re trying to live in.
  • Step 5: Check in nightly. If I feel wired, I reduce evening bright light, add a wind-down routine, or push the shift by only 60 minutes the next day.

Eastbound example I’ve actually used

Let’s say I fly from New York to Paris (6 hours ahead). My home bedtime/wake time is 11:30 p.m./7:00 a.m. EDT; in Paris, the target is 11:30 p.m./7:00 a.m. CET.

  • Two days pre-travel: Bed 10:30 p.m., rise 6:00 a.m. (seek outdoor light 6:30–8:00 a.m.; avoid bright screens after 9:30 p.m.). Move dinner 30–60 minutes earlier.
  • Day before travel: Bed 9:30–10:00 p.m., rise 5:30 a.m. (morning light again, brief walk). Pack so the evening is calm, not frantic.
  • Flight night: I set my watch to Paris when boarding. I treat cabin time after “Paris 10:00 p.m.” as night: eye mask, earplugs, no seatback TV glow if I can help it. I don’t panic if sleep is short.
  • Arrival day: Land mid-morning Paris time ⇒ seek bright light late morning to early afternoon; short walk outside. Nap only if needed, cap at ~20–30 minutes before 3:00 p.m.
  • First night: Wind down starting 10:00 p.m., lights low, screens off, cool room. In bed ~11:00–11:30 p.m. If I’m awake at 3:00 a.m., I keep lights dim, breathe, and aim to rest; I avoid blasting myself with phone light.
  • Days 2–3: Maintain wake 7:00 a.m., get outdoor light 7:30–9:00 a.m.; keep caffeine to morning; protect the 10:00 p.m.–midnight window from bright light. The drift usually finishes here.

Westbound example that felt easier on my brain

Flying Los Angeles to Honolulu (3 hours behind) or Paris to New York (6 hours behind) usually feels easier because delaying the clock aligns with many people’s natural tendency to stay up later.

  • Pre-travel: Push bedtime later by 60–90 minutes the night before. Wake time follows.
  • Arrival day: Seek late-evening light (outdoor light or brightly lit indoor spaces) to delay the clock. If I get drowsy too early, I plan a walk or social time after dinner.
  • First two nights: Bed when I can still achieve a full sleep window that ends near local morning (e.g., 11:30 p.m.–7:00 a.m.). If I wake at 4:30 a.m., I keep the lights low and try a quiet activity in dim light; I avoid sunrise-level brightness until my target wake time.

How I set bed and rise times without wrecking my days

This is the part I wish I’d learned sooner: I don’t need a perfect first night; I need strong anchors and consistent signals.

  • Pick a non-negotiable wake time. I anchor on wake time first because morning light and activity shove the clock in the direction I want. Even on a rough night, I try to get up at the planned time and get outside for light.
  • Protect a calm pre-sleep hour. I plan a wind-down—dimmer lights, lukewarm shower, light stretching, and a screen cutoff—so the new bedtime has a runway.
  • Use “anchor sleep” on brutal itineraries. If the schedule is chaotic, I aim for a guaranteed 4–5 hour core sleep in the destination night window, then add an early-afternoon nap if needed. The anchor keeps the clock from scattering.
  • Keep the shift humane. I move 60–120 minutes per day unless work demands otherwise. If I feel wrung out, I downshift to 60 minutes and accept a slower adjustment.
  • Plan light avoidance. Sunglasses or a hat after local dusk (for eastbound advances), or avoiding bright light early local morning (for westbound delays), keeps me from undoing the shift I just earned.

Meal timing, caffeine, and melatonin without the magic thinking

Meals and caffeine are like background music for the body clock: not as dominant as light, but they set the tone. I move breakfast and lunch toward the destination day as soon as I can, and I keep most caffeine to local morning/late morning. If I try melatonin, I treat it as a signal, not a sedative. People respond differently, products vary, and more isn’t necessarily better. The NIH’s consumer fact sheet is a solid primer if you’re evaluating whether and how to use it: NIH ODS on Melatonin. I also like the way sleep medicine groups emphasize timing (not just dose) for jet lag and circadian issues, e.g., this plain-language overview: AASM Sleep Education on Jet Lag.

  • If advancing (eastbound): Consider a small, earlier dinner; dim lights; minimize late caffeine; morning outdoor light soon after target wake time.
  • If delaying (westbound): Keep some light and activity into the late evening; avoid bright light too early the next morning; a later, light dinner can help delay cues.
  • Hydration and alcohol: I drink water liberally and keep alcohol light or skip it on arrival days—sleep depth and recovery are better that way.

What I do on very short trips

If I’m in a new time zone for fewer than 3 days, I often don’t try to fully adapt. Instead I keep my home schedule on purpose—especially for calls or presentations—and focus on sleep quality rather than local alignment. That means black-out curtains, a sound machine app, and careful light timing so I can be alert during key hours. I still adjust meals and caffeine to match the events that matter, but I stop worrying about being fully “on local time.”

  • Two-day conference abroad: Keep home-time anchors, schedule strategic naps, and lean on bright light during the specific local hours I need to perform.
  • Sport or performance days: I build a “peak window” locally (2–4 hours) with light, movement, and moderate caffeine, then prioritize recovery afterward.

Signals that tell me to slow down and double-check

Most jet lag is uncomfortable but self-limited. Still, I keep an eye on a few flags. If I notice these, I reconsider my plan and look for help:

  • Safety concerns: If severe sleepiness could put me or others at risk (e.g., driving), I reorganize plans, carpool, or rest instead.
  • Persistently fragmented sleep: If nights stay chaotic for more than 1–2 weeks after a big shift, I look at sleep hygiene, light exposure, and whether a separate sleep issue might be in the mix.
  • Underlying conditions or medications: If I have a sleep disorder, take medications that affect alertness, or am pregnant, I get personalized advice rather than winging it.
  • Severe insomnia or mood symptoms: I don’t white-knuckle through—clinicians can help tailor a plan, and sometimes the fix is simpler than I expect.

For clear, trustworthy background reading when something feels off, I like patient education pages that explain next steps without scary language, e.g., MedlinePlus on insomnia and Mayo Clinic on jet lag.

My small, repeatable checklist for fixing bed and rise times

  • Pick the target: Bed/Wake for the destination.
  • Shift steadily: 60–120 min/day toward target; expect a few imperfect nights.
  • Use light as medicine: Morning light for advances; late-evening light for delays; avoid the opposite window.
  • Protect the wind-down: Screens off, lights low, short routine every night.
  • Keep naps short: If needed, limit to ~20–30 min before midafternoon.
  • Time food and caffeine: Eat and sip mostly in the “new day.”
  • Be kind to your schedule: Meetings and workouts can slide a bit while you’re adjusting.

What I’m keeping and what I’m letting go

What I’m keeping: the idea that small, consistent signals beat willpower, that wake time is the most powerful anchor, and that the sun does most of the work if I let it. What I’m letting go: the fantasy of knocking jet lag out in one night, the guilt of a nap when it’s the right tool, and the habit of doom-scrolling at 3:00 a.m. with the screen on max brightness.

FAQ

1) How many days does it usually take to adapt?
Most people shift about 1–2 hours per day. A 6-hour change often settles in 3–5 days with consistent light and anchor times.

2) Is melatonin necessary?
Not always. Many travelers do fine with light and schedule shifts alone. If you consider melatonin, timing matters as much as dose. A reliable, balanced overview is here: NIH ODS.

3) Should I nap on arrival?
Short naps (about 20–30 minutes) before midafternoon can help alertness without undermining the new bedtime. If a nap makes it hard to sleep that night, try skipping it the next day.

4) What’s the one thing that helps the most?
Morning outdoor light in the destination time zone—plus a steady wake time—moves the needle more than almost anything else.

5) What if my trip is only two or three days?
Consider staying on home time and using targeted light exposure to be alert during key local hours, rather than fully adapting. Protect sleep quality and keep routines simple.

Sources & References

This blog is a personal journal and for general information only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not create a doctor–patient relationship. Always seek the advice of a licensed clinician for questions about your health. If you may be experiencing an emergency, call your local emergency number immediately (e.g., 911 [US], 119).