How do you get over jet lag fast?
Updated 2026-07-04
The fastest way to get over jet lag is to shift your body clock with well-timed light, because light is the strongest thing that moves your rhythm. The simple rule: flying east (where you need to fall asleep earlier), seek bright light in the morning at your destination and avoid bright light late; flying west (where you need to stay up later), get bright light in the evening and avoid it too early. Getting on the destination's meal and sleep schedule right away, and starting to shift a day or two before you fly, both speed it up.
Why jet lag happens
Your body clock is set to your home time. When you cross time zones, your internal day is suddenly out of sync with the local one, so you feel wired at night and foggy in the day until your clock catches up, usually shifting about an hour a day on its own.
You can speed that up by giving your clock the right light at the right times.
The direction rule (this is the important part)
Traveling east shortens your day, so you need to move your clock earlier (advance it). Bright light in the local morning advances your clock; bright light late at night would push it the wrong way, so avoid it.
Traveling west lengthens your day, so you need to move your clock later (delay it). Bright light in the local evening delays your clock; avoid bright light too early in the morning at first.
Crossing many time zones east can be tricky because very early-morning light can accidentally shift you the wrong way. When in doubt for long eastward trips, get light in the mid-to-late morning rather than at dawn for the first day or two.
Pre-adjust before you fly
For a big trip, start nudging your schedule a day or two early: for an eastward trip, wake and sleep a bit earlier each day and get bright morning light; for westward, shift later. Arriving already part-adjusted takes the edge off.
On arrival, adopt the local schedule immediately, eat meals on local time, and get outdoors for daylight when the rule says to seek light.
Light strategy by direction of travel
| Direction | Your clock needs to | Seek bright light | Avoid bright light |
|---|---|---|---|
| Eastward (e.g. US to Europe) | Move earlier (advance) | Local morning | Late evening |
| Westward (e.g. Europe to US) | Move later (delay) | Local evening | Early morning (first day or two) |
How to beat jet lag with light
- 1Know your direction
East means you need to shift earlier; west means later. This decides when to seek and avoid light.
- 2Pre-adjust for a day or two
Shift your sleep and wake times, and your light, toward the destination before you leave.
- 3Switch to local time on arrival
Eat, sleep and wake on the destination's clock immediately, even if it feels wrong.
- 4Time your light
Seek bright light when the rule says to, and dim, blue-free light when it says to avoid it.
- 5Be consistent for a few days
Keep the pattern until you feel synced; most people shift about a zone per day with good light timing.
Frequently asked
How long does jet lag last?
As a rough guide, your clock shifts about one time zone per day on its own. Well-timed light can speed this up. So a five-time-zone trip might take up to about five days to fully settle without help, and less with a deliberate light plan.
Is it worse to fly east or west?
For most people, flying east is harder, because moving your clock earlier is more difficult than delaying it. Westward trips, where you stay up later, tend to be easier to adjust to.
Does light really help with jet lag?
Yes. Light is the strongest external cue for your body clock, so getting bright light at the right time (and avoiding it at the wrong time) is the most effective non-drug way to re-sync after travel.
Can I prevent jet lag before I travel?
You can reduce it. Shifting your sleep, wake and light exposure toward the destination's schedule for a day or two before you fly means you arrive already part-adjusted.
Because OIO runs on hours you set, you can use it to pre-adjust before a trip: shift your wake and wind-down times a little earlier or later each day and the bulb's day-to-night light arc moves with you, helping you nudge your clock toward the destination from your own bedroom. It is not a medical treatment for jet lag, but it makes deliberate light timing easy to run at home.
- CIE S 026:2018. System for Metrology of Optical Radiation for ipRGC-Influenced Responses to Light.
- Brown et al. (2022). Recommendations for daytime, evening and nighttime indoor light exposure. PLOS Biology.
- Berson, Dunn & Takao (2002). Phototransduction by retinal ganglion cells that set the circadian clock. Science.
- WELL Building Standard v2, Feature L03: Circadian Lighting Design.
This guide is general information about light and circadian rhythm, not medical advice. OIO is not a medical device and does not diagnose, treat or cure any condition. If you have a persistent or serious sleep problem, talk to a clinician.