Jet Lag Prevention: Master Your Body Clock for Seamless Travel
Originally sent on 17 August 2025
Today is a glorious day in London—blue skies, warm air, the kind of light that makes you forget why anyone ever chases the sun elsewhere. But August is peak holiday season, and every trip abroad carries one hidden tax on your body clock: jet lag. A few years ago I laughed jet lag off as inevitable—falling asleep too early, waking up at ridiculous hours, 4 am with the children at 4 am. Now I know jet lag is not inevitable. It’s physics and biology—and when you understand how light and food reset your inner clock, you can bend time to your advantage.
DATA — Where insight becomes impact
Your body runs on a circadian rhythm—roughly a 24‑hour cycle governed by your brain’s master clock in the suprachiasmatic nucleus. This clock synchronises to external cues called zeitgebers—mainly light and food. Travelling east (phase advance) means you lose light hours: dawn happens earlier than your body expects, making it hard to stay awake in the evening. Travelling west (phase delay) means you gain light hours: dawn happens later than your body expects, making it hard to fall asleep at night. Studies show we shift about 1 hour per day east and 1.5 hours per day west. Circadian disruption shrinks the hippocampus (your learning and memory centre), slows reaction times and increases disease risk. Jet lag isn’t a mystery; it’s misplaced light and mistimed meals. When you master those two levers, you stop fighting time zones and start aligning with them.
DEVICES — Track it to hack it
On my recent trip to India to speak at the Indian Institute of Management, here’s what I packed and why:
Blue‑blocking glasses for the flight home. Put them on after dinner on the flight to reduce melatonin suppression and shift your brain clock toward “night mode.”
Blue‑stimulating glasses for arrival. Useful eastbound: wear them at new local wake time to suppress residual melatonin and shift your brain clock toward “morning mode.”
Melatonin (3 mg) to be taken eastbound at new local bedtime to accelerate circadian advance.
Travel comfort kit—supportive head pillow, oversized eye mask and ear plugs. Comfort reduces micro‑disturbances (light leaks, noise, seat elevation).
Oura ring to track HRV, REM and sleep latency—helpful for seeing how well you’re adjusting to time‑zone shifts.
Continuous glucose monitor (optional) to check whether carbohydrate timing (morning vs evening) is shifting metabolic clocks.
DECISIONS — From knowing to doing
Here’s your Jet Lag Prevention Protocol—save it for your next triplocalhostlocalhost:
Day of arrival
Eastward travel: You’ll find it hard to wake in the morning and sleepy too early at night. Goal: push your clock forward.
Westward travel: You’ll stay up too late and sleep in too long. Goal: delay your clocklocalhost.
Light
New wake time: Maximise bright light at your new wake time to stop melatonin production. Take a morning walk or use blue‑stimulating glasseslocalhost.
Evening: Reduce light with blue‑blocking glasses or dim lighting; put blue‑stimulating glasses on in the evening when travelling west; keep early mornings dim when travelling eastlocalhost.
Food
Eastbound: Have a carbohydrate‑rich breakfast within 30 minutes of waking—this anchors metabolism to the start of the day. Enjoy an early, light, protein‑rich dinnerlocalhost.
Westbound: Eat a late carbohydrate dinner about two hours before new bedtime; insulin rises support tryptophan, serotonin and melatonin for easier sleep onsetlocalhost.
Supplements
Take 1–5 mg of melatonin at the new local bedtime when travelling east. If travelling west or if you prefer not to use melatonin, rely on light and food cues.
More tips
Day before travel: Get morning sunlight within 30 minutes of waking; go to bed 60 minutes earlier; no caffeine after midday; no alcohollocalhost.
Day of travel: Hydrate every hour; eat at destination mealtimes; block blue light at destination dusk; if arriving during the day, seek bright light; if arriving at night, use an eye mask and ear plugslocalhost.
Remember: Jet lag is about timing light and meals. Master these and your body aligns with local time.
Case in point: A global CEO couldn’t understand why he felt jet‑lagged for days even on short trips. We ran a series of melatonin hormone profiles and discovered his melatonin surge was delayed by three hours compared to averagelocalhost. With data, we timed his light exposure and carbohydrate intake precisely. On his next trip to New York, he was leading meetings on day two instead of fighting fatiguelocalhost.
DIARY — Where you’ll find me…
Last week: In Cambridge, talking to the Cambridge Vacuum Engineering Group about longevity. They recognised that investing in employee health is investing in company performancelocalhost. This week: I’m looking forward to my live call in The Million Hour Club and revealing members’ biological ages. Next week: Podcast recordings and a first‑of‑its‑kind retreat—more to share soonlocalhost.
DISTINCTION — A thought to pause on…
Jet lag is the only time travel we get—don’t let misaligned cues steal hours from your life. Prepare with light, meal timing and the right tools, and your body clock will take you further.