Plan your jet lag recovery
- Select your departure and arrival cities.
- Enter your flight duration and direction.
- Follow the personalized light and sleep schedule.
Jet Lag Planner
Decode jet lag recovery. Reset your body clock faster with light therapy science.
Method Light therapy
Coverage Global timezones
Use case Travel prep
Jet Lag Planner
Get a personalized schedule to adjust faster
hours
New YorkUTC-5
6hahead
ParisUTC+1
How light resets your body clock
Your circadian rhythm is controlled by a small region in your brain called the suprachiasmatic nucleus (SCN). This internal clock regulates sleep, hormone production, body temperature, and other functions on a roughly 24-hour cycle. When you cross time zones rapidly, your internal clock remains synchronized to your origin time zone, causing jet lag symptoms.
Light is the most powerful zeitgeber (time-giver) for your circadian system. When light hits specialized cells in your retina, it sends signals to the SCN, which then adjusts the production of melatonin—the hormone that makes you sleepy. By strategically timing light exposure, you can shift your body clock in the desired direction.
The phase response curve (PRC) shows that light exposure in the early morning advances your clock (shifts it earlier), while light in the evening delays it (shifts it later). This is why eastbound travelers should seek morning light and avoid evening light, while westbound travelers benefit from the opposite approach.
Strategies for faster recovery
- Pre-flight adjustment: Shift your sleep schedule 1-2 hours per day toward your destination time zone starting a few days before departure.
- During flight: Set your watch to destination time immediately. Stay hydrated, avoid alcohol and caffeine, and sleep only if it's nighttime at your destination.
- Upon arrival: Get sunlight exposure during daytime hours. If you arrive in the morning, stay awake and get bright light. If you arrive at night, go to sleep at a reasonable local time.
- Melatonin: Consider taking 0.5-3mg of melatonin 30-60 minutes before your target bedtime for the first few nights at your destination.
This is a planning tool, not medical advice
- Individual responses to jet lag vary based on age, chronotype, and health.
- Recovery typically takes 1 day per time zone crossed when traveling east, and slightly less when traveling west.
- Consult a healthcare provider before taking melatonin or if you have sleep disorders.
- Shift workers can also use these principles for schedule transitions.
Common questions about jet lag
How does jet lag work?
Jet lag occurs when your internal body clock (circadian rhythm) is out of sync with the local time at your destination. Your body produces melatonin and other hormones based on your home time zone, causing you to feel sleepy or alert at the wrong times.
Why is eastbound travel harder than westbound?
Traveling east shortens your day, which is harder for the body to adjust to than lengthening it (westbound travel). Our circadian rhythm runs slightly longer than 24 hours, making it easier to stay up later than to go to sleep earlier. Eastbound travel typically requires about 1 day of adjustment per time zone crossed.
How does light exposure help with jet lag?
Light is the most powerful signal for regulating your circadian rhythm. Morning light helps reset your body clock earlier, while evening light delays it. By strategically seeking or avoiding light at specific times, you can help your body adjust faster to the new time zone.
Should I take melatonin for jet lag?
Melatonin can be effective for jet lag when used correctly. Take 0.5-3mg about 30-60 minutes before your desired bedtime at the destination. For eastbound travel, take it in the evening. For westbound travel, it's usually not needed. Always consult with a healthcare provider before starting any supplement.