Fasting and Travel: A Report From the Field
I’ve been noodling with intermittent, morning fasting recently, and just put it to practice on a trip to Greece. Here’s my experiences with both: I hope my anecdotes are helpful, and shed some light on an experience which others may be considering.
Food
Food is a finicky little problem for me. Every meal, every bite, is a joyous little moment in my day, one of visceral delight and pleasure. Deriving experiential pleasure from caloric ingestion is a very tricky thing to navigate: I’ve learned I must anticipate this when I plan a meal, its ingredients, and its size, and need to be present for every bite. Without imposing a heavy-handed, highly cognitive self-regulation during a meal, every nibble, even when I’m full and sated, will earn a stamp of approval from my naïve and error-prone mental arithmetic: on its own, each bite brings immediate happiness, and incurs a small, abstract, longer-term cost, so I nibble my way from “sated and full” to “regret and sadness”.
I did a small project with two meditation group friends on being more mindful of one’s habits, and my odd tendencies of food consumption came to mind. I evaluated some changes to my environment and behaviours which could be introspective, or perhaps affect a change directly. Intermittent fasting has been one of the more interesting ones.
My first fasts have been in the morning: rather than eating breakfast, I stretch out the period of foodlessness from dinner the night before through to lunchtime. In practice, it’s simple: in the morning, I pick a time to eat lunch, around 12:30 or 1 PM, and take a moment to plan out a healthy meal. Once that’s figured out, I make a cup of black coffee (importantly, no milk or sugar) and go on with my day. (I don’t drink much coffee, but I’ve found a good half or full cup of coffee helps keep me energized and distracted from my grumbling stomach.)
I’ve been surprised and impressed by my brain and body’s reactions to the fasts. They feel clarifying and simplifying: there’s no meal preparation or cleanup, and having my lunchtime menu and time planned out helps silence my brain’s normal angst and perpetual hand-wringing about hunger and food: “Am I hungry now?” “When did I eat last?” “Is it ok to eat now, or should I wait?” “Should I snack, or wait and make a full meal?” “Rice pudding is an acceptable breakfast, right?” “I don’t really want to take the time to cook, but I’m hungry…” Also of significance: my body’s hunger subsides an hour or two after my usual breakfast time, and it doesn’t seek revenge at lunchtime and come roaring back.
I’ve done a small morning fast for a few mornings while working at home, and during a couple of travel days on the road. I’ve found it easier than I’d expected, and a very calm experience. It reminds me, in some strange ways, of meditation: it’s a very deliberate removal of a stimulus from one’s environment, and in its absence, there’s a bit more space and free airtime for other things.
Around the same time as I began my fasting project, I realized I might have a trip from San Francisco to Greece on my schedule. I’d wanted to try a fasting-oriented approach to coping with jet lag, and this was great practice: the fast I’d need to do while traveling would be at least 12 to 16 hours, possibly longer, and I’d be awake for most or all of it. Greece is 10 hours ahead of San Francisco; during a trip to Uganda last summer, also 10 hours ahead, I suffered from jet lag for several days, I was suddenly very interested and motivated to try something new.
The rough principle behind fasting during timezone travel: by removing the day’s normal food schedule cadence, you upend your body’s day and night rhythms. When you break your fast in your destination in the morning, and sync up the rest of your day with the new time zone’s food schedule, your body, hungry for food and eager for stability, takes the hint about the change in time far more easily than if you’d continued eating on a normal schedule. As I explained this to Patrick and Maja: normal international travel is confusing to your body. You wake up, eat breakfast, lunch, then dinner after dinner after dinner, a snack, another dinner, one last dinner, and then go to bed. Fasting keeps it simple: wake up [loss of food signal] off the plane breakfast lunch dinner bedtime!
(More reading on jet lag and fasting: a write-up from Harvard Business review on the original research, a bit in Harper’s Magazine, Jezebel with a handy timezone calculator, and the obligatory Lifehacker article.)
So: here I am in Greece, three days after my arrival, and I feel pretty great. Here’s my little story, a few anecdotal data points, from which someone can perhaps draw some inferences or plan out their own fast:
My departure, travel to Europe, and arrival in Greece
I ate my last meal in San Francisco at 10:30 am Pacific: I had a regular night’s sleep, and ate a small breakfast with a small espresso. I fasted for 13 hours, skipping lunch in SFO and dinner on the plane, slept less than an hour on the plane, and ate breakfast shortly before landing in Frankfurt. (Frankfurt is one hour behind Greece, nine hours ahead of SF, and this meal was provided around 8:30 am local, 9:30 am Athens, 11:30 pm San Francisco)
I crash-napped briefly on my next flight, from 3 to 4:30 pm local time (6 to 7:30 am PST), and ate dinner in the airport around 8 pm Athens time. I slept fitfully that night, but did get around 8 hours of rest, from 10:30 pm to 6:30 am (and I caught a pretty delightful sunrise!)
I ate on a regular schedule on my first full day in Greece: a substantial breakfast with a tiny cup of coffee at 8:30 am, and a large lunch at 2 pm. I snacked again at 3:30, and that was my last food for the day. At 6:30 pm, just as the light was fading for sunset, my body crashed hard, probably from the lingering sleep deprivation and general time zone nonsense, and I went to bed. (This was 8:30 am PST: perhaps my body had some fuzzy, lingering memories of sleepy weekend mornings it was trying to recreate.) I woke up at midnight, fairly awake and pretty hungry, and had to keep myself entertained until sunrise and breakfast. So, in sum: 5 hr 30 min of sleep.
I had breakfast at 8:30 am on that second, very insomniac, day, totaling up to a 17 hour fast. I ate on another normal schedule that day: coffee with breakfast, espresso at 11 am, lunch at 1:30, and dinner and drinks around 7:30–8 pm. I was sleepy in the early evening, but stayed up, and crashed into my bed hard at 10 pm. I slept pretty soundly until church bells woke me up at 7 am, for 9 hours of sleep.
In Review
My daily energy has felt quite completely normal from the morning through daytime hours until 6 pm. Even today, my third full day here, my body felt drained and sleepy right around 6. (Then again: I get yawny right around 9:30 pm on a normal day at home, so maybe I’m just a bit early of that mark.)
My sleep has been weird: I slept real funky that first night, had a bad night on the second, and I’m not sure if last night’s rest was the start of a better trend, or a post-insomnia correction.
My appetite has been in sync with the usual local mealtimes. It’s nice to be hungry when places are open, and aside from night two, to not wake up to a growling stomach.
What I think has been effective:
I’ve avoided an unnecessary amount of caffeine. I’m happy to go to bed a bit early: 8 or 9 pm is fine by me, as long as I get more than five or six hours of rest.
I’ve avoided drinking for the first couple of days. It’s pretty normal to sober up while sleeping, and your body has a brief middle-of-the-night wakefulness episode as a result. If that were to occur while my “middle of the night” was actually “10 am Pacific time”, I’d expect to have a tremendously difficult time sleeping.
I’ve stuck to normal meal schedules. I woke up fairly damn hungry at midnight that second night, but I knew a 2 am snack would do more harm than good. I drank plenty of water and kept myself occupied until it was breakfast time, and I think that extended fast probably helped cement my body into the local timezone.
What I’d do differently next time:
I wish I’d done a longer fast during the flight out. If I’d skipped breakfast on my day of departure, my total fast from dinner in SF to breakfast in Frankfurt would have been 26 hours, instead of 13. I think this would send a much stronger signal about the time change.
I’d consider being less rested for my flight, or traveling during a different time of day. When traveling west to east and landing in the morning hours, you’ve effectively excised the origin time zone’s sleep hours from that day’s schedule. If I’d had my usual bedtime occur while on the plane, I’d have gotten three or four hours of rest, breaking up an irrationally lengthy day. (Going from 8 am wake-up in San Francisco to a 9 pm bedtime in Greece is a 27 hour wakefulness marathon. It’s pretty funky.) All things being equal, I’d prefer to sleep my way through a fast, especially if it’s more than 20 hours.









