“I travel so much for work that I can never stick with a diet.”
“Client dinners and business meals throw my eating completely off track.”
“I’m too busy to find time to take care of my health.”
A lot of working professionals probably share worries like these.
The truth is, fasting (intermittent fasting) is one of the health habits best suited to busy professionals.
That’s because you don’t need any special ingredients or cooking. You “just create a window of time when you don’t eat.”
In this article, I’ll walk you through a complete guide to help professionals who deal with lots of business trips, client entertaining, and overtime keep up fasting without strain.
- 1 Why Fasting Suits Working Professionals
- 2 Choosing a Fasting Style for Working Professionals
- 3 Sample Fasting Schedules for Business Trips, Client Dinners, and Overtime
- 4 Tips for Keeping Your Fast on Track at Client Dinners and Business Meals
- 5 Managing Your Condition on the Road: Hydration, Sleep, and Jet Lag
- 6 Things to Watch Out for When Fasting on Business Trips
- 7 Frequently Asked Questions About Fasting on Business Trips and for Working Professionals
- 8 Busy Professionals, Use Fasting to Balance Your Health and Your Work
Why Fasting Suits Working Professionals
Fasting Is a Health Habit Where You “Do Nothing”
Typical diets require you to manage “what you eat.”
Counting calories, choosing ingredients, preparing meals: all of that is simply too much of a burden for busy professionals.
Fasting, on the other hand, means you only manage “when you eat.”
You don’t have to change much about what’s on your plate, and there’s no special preparation required.
Whether you’re in a hotel on a business trip or it’s the day of a dinner with a client, the strength of fasting is that you can do it as long as you have a clock.
What Is 16-Hour Fasting, Anyway?
The easiest approach for professionals to adopt is “16:8 fasting,” where you don’t eat for 16 hours of the day and have your meals within the remaining 8 hours.
For example, if you finish dinner at 8 p.m. and eat nothing until noon the next day, that’s 16 hours.
About 7 of those hours are spent sleeping, so in many cases the only time you actually feel hungry is for a few hours in the morning.
During the hours you don’t eat, you stick to calorie-free drinks such as water, tea, and black coffee.
The basics are explained in detail in “【The Complete Beginner’s Guide】What Is Intermittent Fasting? Types, Benefits, How to Do It, and Why You Might Not Be Losing Weight, Explained Simply.”
Fasting Boosts Your Business Performance
Fasting comes with side benefits that professionals will appreciate.
- No more afternoon drowsiness: blood sugar spikes disappear, and the sluggishness after lunch goes away
- Better concentration: ketone bodies become an energy source, and your brain works steadily
- You gain time in the morning: skipping breakfast shortens the time it takes to get ready in the morning
- More options when eating out: once you set the hours when you eat, you have more freedom in what you eat
My Own Experience with Business and Fasting
I started fasting around the time I began working as a freelancer.
I was working from morning until late at night and couldn’t spare time for my health, which is exactly why fasting, where you “only decide when to eat,” was a good fit for me.
These days, thanks to fasting, my focus lasts all afternoon, and my productivity at work has clearly gone up.
Choosing a Fasting Style for Working Professionals
Recommended Fasting Styles by Type
The fasting style you can maintain comfortably depends on how you work.
| Work type | Recommended style | Key point |
|---|---|---|
| Office worker with a regular schedule | 16:8 fasting (12 p.m. to 8 p.m.) | Skip breakfast to free up your morning. Eat lunch and dinner as usual |
| People who travel or eat out a lot | 16:8 fasting (flexible) | On days with client entertaining, set your eating window from late afternoon into the evening. Adjust by skipping the next morning |
| People with irregular work schedules | 12- to 14-hour fasting | Don’t fix your daily fasting hours; aim to “leave 12 hours after your last meal” |
| People who travel abroad often | Time-zone-adaptive fasting | Instead of matching local time, follow a rule of “no eating for 4–6 hours after waking up” |
There’s no need to insist on 16 hours from the start; it’s perfectly fine to begin by leaving a 12-hour gap.
Techniques for Keeping Up Fasting on Business Trips
- Say no to breakfast: the hotel buffet is tempting, but simply deciding “today is a skip-breakfast day” keeps your fast going
- Pass on the in-flight meal: it’s fine to decline airline meals. You can get through the flight with just water, tea, and black coffee
- Fit lunch meetings into your lunch window: if you set an eating window from 12 p.m. to 8 p.m., business lunches are no problem
- Fast the morning after a dinner meeting: the morning after eating late, eating nothing until lunch helps make up for the previous day’s intake
If You’re Shopping at a Convenience Store on the Road
On business trips, there will probably be days when you grab the meals in your eating window from a convenience store.
When that happens, the key is not to settle for just onigiri (rice balls) or sweet buns, but to choose with protein and vegetables in mind.
- Protein such as ready-to-eat chicken breast, boiled eggs, or grilled fish
- Pre-cut vegetables or salads, and hearty soups or miso soup
- Soy products such as natto (fermented soybeans) and tofu
- A small handful of unsalted roasted nuts when you get a little peckish
If you start your first meal after a fast with soup or salad, it becomes easier to prevent a sudden rise in blood sugar.
Stop “Eating Just Because” While on the Move
Something surprisingly common on business trips is snacking while traveling.
Plenty of people eat as a “travel companion” even when they’re not hungry, like buying sweets at a station kiosk or absentmindedly having a canned coffee and some snacks on the shinkansen (bullet train).
If you decide ahead of time that it’s only water or tea while you’re on the move, it becomes easier to stick to your fasting hours.
Sweetened canned coffee and soft drinks also contain sugar, so try to choose black coffee or unsweetened tea instead.
Sample Fasting Schedules for Business Trips, Client Dinners, and Overtime
Here are sample daily schedules for three common patterns.
Use whichever one is closest to your own plans as a reference, and shift the times earlier or later to suit you.
Pattern 1: A Regular Business Trip Day
| Time | Activity |
|---|---|
| 6:00 | Wake up; black coffee or water only |
| 6:00–12:00 | Fasting (travel and morning meetings) |
| 12:00 | Lunch (end of fast) |
| 12:00–20:00 | Eating window (lunch, snacks, and dinner OK) |
| After 20:00 | Fasting resumes (water and tea only) |
If you use your morning travel and morning meetings as fasting time, the hours pass before you even have a chance to feel hungry.
For lunch, it’s a good idea to pick a place where you can sit down and eat slowly once your meetings are over.
Pattern 2: A Day with a Client Dinner or Business Meal
| Time | Activity |
|---|---|
| 7:00 | Wake up; black coffee only |
| 7:00–13:00 | Fasting (skip breakfast) |
| 13:00 | Light lunch |
| 19:00–21:00 | Client dinner or business meal (eat and drink normally) |
| Next morning until 13:00 | Fasting (16 hours from the night before) |
On days with client entertaining, keeping lunch light lets you enjoy dinner while still avoiding overeating over the whole day.
The next day, you’ll leave 16 hours after the previous night’s meal, so remember that lunch will be a little later than usual.
Pattern 3: A Day of Late-Night Overtime
| Time | Activity |
|---|---|
| 7:00 | Wake up; black coffee only |
| 12:00 | Lunch (end of fast) |
| 18:00 | Dinner (last meal of the day) |
| After 18:00 | Fasting resumes (water and coffee only, even during late-night overtime) |
| 10:00 the next day | Start eating the next day (16 hours achieved) |
A common pattern on overtime days is ending up eating a convenience-store bento or instant noodles late at night.
If you finish dinner in the early evening, you can avoid eating late at night and also give your stomach a rest before bed.
If you feel hungry while working late, sipping warm tea or plain hot water can help take your mind off it.
Thinking in Weeks to Balance Things Out
When business trips and client entertaining pile up, keeping a strict 16 hours every single day is hard.
At times like that, thinking “by the week” rather than “by the day” takes a huge weight off your mind.
In a week full of business meals, it’s enough to balance things across the whole week, for example by fasting a little longer on days with nothing scheduled.
Tips for Keeping Your Fast on Track at Client Dinners and Business Meals
For working professionals, client entertaining and business meals are unavoidable.
Here are some tips for enjoying those meals while still keeping up your fasting.
Pay Attention to the Order You Eat In
Even with a multi-course meal or izakaya (Japanese pub) dishes, simply changing the order you eat in changes the load on your body.
The basic rule is to eat salads, appetizers, and sashimi first, and save fried foods and rice dishes for later.
Eating vegetables and protein first will likely make it easier to keep your blood sugar from shooting up.
With shared dishes, one approach is to put extra vegetables on your own plate.
How to Handle Alcohol Wisely
There are many occasions to drink at business meals, but how you drink makes a big difference to how you feel the next day.
- If you make a habit of “chasers,” drinking about as much water as alcohol in between, it helps prevent overdrinking and tends to ease that sluggish feeling the next morning.
- If you get to choose what to drink, it’s a good idea to pick something low in sugar.
- On days you’ll be drinking, planning ahead so that you drink within your eating window makes it harder for your fasting rhythm to fall apart.
Treat That End-of-Night Ramen or Dessert as “Something to Adjust for the Next Day”
The ramen at the end of the night after a business dinner, or snacks at the after-party, tend to be big pitfalls for fasting.
When you really can’t say no because of work relationships, just accept it and decide, “I’ll make my fasting time longer the next morning to make up for it.”
What matters is not giving up with “That’s it, I’ve blown it” after one round of overeating, but getting back to your usual rhythm from the next day.
For how to get back on track when you feel like quitting, “【It’s OK If You Slipped】5 Reasons People Quit Fasting, and 7 Steps and Mindset Tips to Restart Successfully” is a helpful read.
Take the Edge Off Your Hunger Before the Meal
If you go to a business dinner extremely hungry, you tend to dive in and overeat from the very first dish.
As long as you’re within your eating window, having a little unsweetened yogurt or a few nuts before the meal can keep you from wolfing down your food.
At the meal itself, try to focus more on enjoying the conversation than the food, and savor each bite slowly.
Managing Your Condition on the Road: Hydration, Sleep, and Jet Lag
On business trips, travel and unfamiliar surroundings put more strain on your body than you might think.
To get the most out of fasting, pay attention to managing your condition beyond just food.
Hydrate More Often Than Usual
The air on planes, on the shinkansen, and in hotel rooms is often dry, and your body loses water without you even noticing.
While fasting, you also get less water from food, so frequent hydration, even more than usual, is essential.
Having a bottle of water ready before you set off lets you sip little by little before you get thirsty, which gives you peace of mind.
Tips for Sleeping Well Even in a Hotel
It’s said that when you don’t get enough sleep, hormones that increase appetite go up, making you feel hungry more easily.
On business trips, put away your phone and laptop early before bed, and make the room dark and quiet to get ready for sleep.
If you finish dinner early, you can fall asleep with a settled stomach, which also tends to improve the quality of your sleep.
Jet Lag on International Trips and Fasting
On international business trips, time differences throw off your body clock, making you more prone to feeling sluggish and sleepy.
You’ll be sitting for long stretches while traveling, so make a point of getting up now and then and moving your legs, even on the plane.
Once you arrive, getting morning sunlight to wake your body up and keeping your mealtimes consistent will likely make it easier to get your body’s rhythm back in order.
For fasting, following the rule introduced in the table above, “no eating for 4–6 hours after waking up,” makes it easier to keep going without being thrown off by the local time.
Walk a Little in Your Spare Time
On business trips, you tend to spend long hours sitting in meetings, at a desk, or in transit.
Make time to move your body with small tweaks, like walking one station’s distance from your hotel to the venue, or taking the stairs instead of the elevator.
A short walk also gives you a change of pace and makes it easier to take your mind off hunger while fasting.
Things to Pack in Your Business Travel Bag
A little preparation goes a long way toward keeping up fasting on the road.
- A reusable bottle you can fill with water and carry around
- Tea bags or single-serve drip coffee
- Unsalted roasted nuts for your eating window
If you can boil water in your hotel room and make tea or coffee, you can spend your morning fasting hours calmly.
Things to Watch Out for When Fasting on Business Trips
Don’t Push Yourself When You’re Feeling Unwell
On business trips, fatigue builds up easily, and you’re more likely than usual to get sick.
If you feel like you’re coming down with a cold or you’re very tired, take a break from fasting, eat properly, and make resting your body the priority.
Fasting is a means of getting your body in good shape, and pushing yourself so hard that it affects your work would defeat the whole purpose.
Watch Out for Lightheadedness Before Driving or Important Moments
Until you get used to fasting, you may experience dizziness when standing up, lightheadedness, or shaky hands when you’re hungry.
On days when you’ll be driving a rental car or company car for long periods, don’t force yourself to extend your fasting hours.
- If you feel dizzy or break out in a cold sweat, it’s important to stop fasting right away and eat something.
- Just in case, keeping something you can eat right away, like nuts or hard candy, in your bag will give you peace of mind if you ever need it.
- Before an important presentation or negotiation, too, it’s best not to force yourself to stay hungry until you’re used to fasting, and to have something light to eat before you go in.
Replace Salt Too in Hot Weather or on Sweaty Days
On summer business trips or days spent running around to client visits, you lose not just water but also salt through sweat.
If you sweat a lot while fasting, replenish your minerals by adding a little salt to your water or having miso soup during your eating window.
By the time you feel thirsty, you may already be low on fluids, so make a habit of hydrating early and often.
You Don’t Have to Force Yourself to Go Along with Others
There’s no need to go out of your way to explain to people around you that you’re fasting.
When you’re invited to breakfast or lunch, saying something like “I’m keeping mornings light today” or “I’ll just have a coffee” will let you decline without causing any awkwardness.
On the other hand, when the relationship with the other person really matters, it’s also important to be flexible enough to take that day off from fasting.
Fasting is ultimately a habit for your own health, not something worth protecting at the expense of your working relationships.
If You Have a Medical Condition, Talk to Your Doctor
People taking blood-sugar-lowering medication for conditions like diabetes, or those being treated for a chronic illness, may become unwell from fasting.
Be sure to consult your regular doctor before you start fasting.
If any numbers from your health checkup concern you, it’s also safest not to start on your own judgment and to get an expert’s opinion first.
Frequently Asked Questions About Fasting on Business Trips and for Working Professionals
Strictly speaking, drinking alcohol during your fast (outside your eating window) breaks the fast.
However, if you can’t say no because of business relationships, keep it to a minimum and adjust by extending your fasting time the next morning.
Rather than beer, which is high in sugar, a zero-sugar highball (whisky and soda) or shochu (a Japanese distilled spirit) on the rocks has less impact on blood sugar and is a better choice.
It may be a bit tough for the first 1 to 2 weeks until you get used to it, but once you do, you’ll actually go into meetings with sharper focus than when you used to eat breakfast.
The key is to make good use of black coffee and drink plenty of water.
When there’s a time difference, the easiest approach is not to match local time but to follow a simple rule: “Don’t eat for 4 to 6 hours after waking up.”
It also helps reset your body clock.
These symptoms can appear in the early stages of fasting (the first 1 to 2 weeks).
Once you get used to it, your mind actually becomes clearer while fasting.
In the beginning, keep your fasting hours on the shorter side, and avoid long fasts the day before an important meeting.
Busy Professionals, Use Fasting to Balance Your Health and Your Work
Fasting is an incredibly simple health habit: you “just create a window of time when you don’t eat.”
No special preparation or special ingredients are needed.
On business trips, with client dinners, even with late-night overtime, you can keep fasting.
What matters isn’t “doing it perfectly” but “continuing as much as you can.”
Try skipping breakfast starting tomorrow morning.
That alone is the first step toward a fasting business life.
Things will go more smoothly if you first try it for a week on regular weekdays without travel, then bring it into your business trips once your body has adjusted.
Once you’re used to it, you’ll likely notice that your health is most stable precisely during your busiest, most travel-heavy periods.
For tips on using hunger to your advantage to focus on work, also check out “【Hunger = Higher Efficiency⏳】Does Hunger Boost or Hurt Focus? Why Your Mind Gets Sharper for Study and Work, and How to Use It Well.”
▼ Related Articles
- 【The Complete Beginner’s Guide】What Is Intermittent Fasting? Types, Benefits, How to Do It, and Why You Might Not Be Losing Weight, Explained Simply
- 【Hunger = Higher Efficiency⏳】Does Hunger Boost or Hurt Focus? Why Your Mind Gets Sharper for Study and Work, and How to Use It Well
- 【Stop Giving Up After Three Days】How to Make Fasting a Habit, 5 Systems That Keep You Going Through the First 21 Days, and a Week-by-Week Roadmap
- 【It’s OK If You Slipped】5 Reasons People Quit Fasting, and 7 Steps and Mindset Tips to Restart Successfully
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