What to eat the day before and on exam day comes down to two principles you can apply yourself: the heaviness of digestion and the swing of blood sugar. This guide is for anyone facing a university entrance exam, TOEIC, Eiken, or another test. It covers the night before, breakfast, snacks during breaks, caffeine and water, and the tonkatsu good-luck charm, with the reason behind each step.
Here is the conclusion up front. What you eat on exam day really does change your morning edge. But there is no "one right meal that gets you in." There is only one real question: can you read the trade-off between your body (digestion) and your mind (mood) for yourself?
Take tonkatsu, a deep-fried pork cutlet. In Japanese, katsu sounds like the word for "to win," so it is a classic good-luck meal before a big test. Honestly, though, deep-fried food is high in fat and heavy to digest, and it isn't really suited to the hours right before an exam.
Even so, I won't call it absolutely forbidden. If it's a favorite that lifts your mood and lets you carry the "I'll win" charm with peace of mind, that lift can genuinely help your nerves on the day. So I won't flatly declare it a "no."
That is the stance this column on passed.jp takes. Instead of forcing one right answer onto your food, I hand you the reason behind each item: why it works, or why you'd want to avoid it. Once you understand the reasons, you are the one who weighs your own body against your own mood and decides. The goal is to leave you, on the day, able to decide for yourself with the reasons in hand.
One disclaimer up front. Everything I say here about food and nutrition is general — what's commonly said — and not medical advice. Bodies, conditions, and allergies vary, so if anything worries you, please consult a professional.
The scope is what to eat on exam day, food the night before an exam, recommended exam-day meals, and tonkatsu as an exam good-luck charm. The night before, breakfast, and between-section snacks take the lead, and I'll stay concrete to the end.
1. Why does food change your edge on the day?
Two reasons. Digestion pulls blood flow away from your head, and blood-sugar swings break your focus. Get these two, and every later "why it's good" or "why to avoid it" connects.
The first: digestion pulls away blood flow and energy. Right after you eat, your stomach and intestines work on digestion, and blood flow gathers there. This is why people commonly say your head feels foggy right after a meal. So a heavy meal right before the exam tends to work against you.
The second: blood-sugar swings. Eat a lot of carbohydrates at once and your blood sugar spikes, then crashes. That crash is when drowsiness, sluggishness, and lapses in focus tend to hit. Keep blood sugar gentle, and you keep the swings in focus small too.
These two, the heaviness of digestion and the swing of blood sugar, are all you need to remember. Everything that follows ("avoid fried food," "don't binge on sweets," "add protein rather than just carbs") derives from these two.
→ Why it works: A food rule whose reason you understand survives the pressure of the day. A rule you learned as "seems good somehow" is the first to evaporate amid exam-day anxiety. Keep the principle as one clear map, and when you hesitate, you can redraw the judgment yourself.
2. What should you eat the night before the exam?
Familiar, easy-to-digest food, and stop at about 80% full. Dinner the night before is prep for the day's condition. You're not scoring points here; you're building a base that won't crumble for tomorrow's you. Here are the specifics, numbered.
(1) Choose familiar, easy-to-digest food. → Why it works: Stomach trouble tends to come from a new dish you tried the night before. The worst accidents, a heavy stomach or an upset gut on the morning of, are often set up the night before. Save the adventure for after the exam.
(2) Avoid raw food (sashimi, raw oysters, and the like). → Why it works: Taking on food-poisoning risk, of all nights, the night before the exam, is a bad trade. Even if the odds are low, the loss if it hits is too large: the whole exam goes up in smoke. The risk is asymmetric to the return.
(3) Don't overeat. Stop at about 80% full. → Why it works: Going to bed stuffed tends to lower sleep quality and leaves heaviness in the morning. The night's purpose is to make tomorrow's you lighter. A fullness that fights that purpose is one to avoid.
(4) Go easy on alcohol and very greasy food. → Why it works: Alcohol may feel like it helps you fall asleep, but it's said to lower sleep quality. Greasy food lingers in digestion into the morning. Both shave off "tomorrow's lightness."
(5) Shift the tonkatsu charm to the night before. If you really want to eat "winning," there's a compromise: have it the night before rather than right before the exam, and keep the amount small. → Why it works: The heavy digestion of fried food matters less the more time there is before the exam. A small portion the night before settles, more or less, by morning, leaving mainly the mood benefit for the day. Don't ban it; reconcile it with timing and amount. That's this column's basic stance.
3. What should you eat for breakfast on exam day?
Don't skip it, don't overdo it, pair a staple with protein, and finish at least an hour before the start. This is the lead role on the day. The specifics, numbered.
(1) Don't skip breakfast. → Why it works: Facing the exam on an empty stomach tends to leave you foggy from low blood sugar, and focus drops. Even when nerves make eating hard, get something in; a small amount is fine. Zero versus a little makes a real difference in your start.
(2) Combine a staple with protein. Add eggs, natto, or yogurt to your rice or bread. → Why it works: Carbs alone tend to make for larger blood-sugar swings. Eating protein alongside is said to keep the swing gentler. This is "shrink the blood-sugar swing" from Chapter 1, put into practice at breakfast.
(3) Stick to familiar food. Don't try a new dish on the day. → Why it works: Experimenting with your gut on the day gains you little, a slight change of pace at most. What you risk is a rough stomach ruining your whole morning. Just like the night before, risk and return don't balance.
(4) Finish eating at least an hour before the exam starts. → Why it works: Right after eating, blood flow goes to digestion and your head works less well. Work backward so that by start time the peak of digestion has passed. This also connects to planning your whole day backward from the clock.
To be clear again: these are general guidelines, and the amount and timing you need will vary from person to person. Fine-tune against your usual condition.
4. What should you eat right before the exam and during breaks?
A square of chocolate, a banana, or a small rice ball: a light top-up. The aim is just one thing: don't make your blood sugar swing. For long exams or into the afternoon, this snacking is what tells. Numbered.
(1) Light snacks on a break: a square of chocolate, a banana, a small rice ball. → Why it works: You fend off the low blood sugar that creeps in toward the afternoon, without filling yourself up. The goal is to top up a little, not to fill your stomach.
(2) Don't binge on sweets. → Why it works: As in Chapter 1, a big hit of carbs spikes your blood sugar, and the crash that follows tends to make you sleepier instead. The goal is stability, not a top-up. A temporary high from sweets followed by a crash defeats the purpose.
(3) Don't make lunch too heavy. Stop at about 80% full. → Why it works: Fullness steals the first edge of your afternoon. Stack the drowsiness of a full stomach onto a head already tired from the morning, and you can't recover. If there's another peak in the afternoon, keep lunch light.
Choose "what, and how much" along the axis of stable blood sugar. Hold that axis and you can judge for yourself whether the option in front of you serves stability or makes a swing.
5. How should you handle caffeine and water?
Caffeine: if you don't usually drink it, don't down a lot just for the exam; if you do take it, have it a little before the start. Water: small amounts, often. Both become ally or enemy depending on how you handle them, so here are the specifics in their own chapter.
On caffeine.
(1) If you don't usually drink it, don't down a lot just for the exam. → Why it works: A body unused to caffeine can react in unfamiliar ways, such as palpitations or more frequent trips to the restroom. Trying it for the first time in the unusual setting of the exam itself is largely a gamble.
(2) Take it a little before the start, assuming it takes time to kick in. → Why it works: Caffeine doesn't work the instant you drink it; it's said to take time to reach peak effect. If you want the peak to land on the exam, place it a little ahead of the start, not right at it.
(3) Factor in that its diuretic effect makes you need the restroom. → Why it works: An interruption mid-exam breaks your focus. If the trade for the effect is more frequent restroom trips, decide the timing with that included.
On water.
(4) Dehydration tends to bring headaches and a drop in focus, so drink in moderation. → Why it works: Too little water and your head won't stay clear. Rather than scrambling once you're thirsty, put in a little at a time, steadily.
(5) But avoid drinking a lot right before; take small amounts, often. → Why it works: A big drink at once means more restroom trips and interruptions mid-exam. To physically cut interruptions, "a little at a time, ahead of need" works. Prevent it with amount and timing, not willpower.
For both caffeine and water, whether they help varies from person to person. Decide the amount against how your own body usually responds.
6. Should you eat tonkatsu for luck?
The body says "avoid it right before the exam." The mind says "it helps with mood and nerves." How much of each you take is yours to decide. This is the core of the column, so I'll write both sides honestly.
Tonkatsu, sounding like "to win," has become a staple before exams.
From the body's side, fried food is high in fat and slow to digest. "The heaviness of digestion" from Chapter 1 applies directly. Eat a big plate right before the exam and blood flow goes to digestion, dulling your morning edge. So it's a food you'd really rather avoid in the hours just before. I'll say that plainly.
From the mind's side, eating a favorite, and carrying the "I'll win" charm, lifts your mood and brings peace of mind. The biggest enemy in an exam is nerves. If the lift of a favorite food and the reassurance of "I made my luck" ease those nerves, that genuinely can help on the mental front. If a settled mind lets you bring out your usual ability, there are cases where it more than makes up for a little heaviness in digestion.
So I won't flatly declare "tonkatsu is a no." When body and mind clash here, how much of each you take is yours to decide. That said, here are the concrete compromises.
(1) Shift it to the night before, not right before the exam. Time solves the heaviness of digestion. The night before leaves the mood benefit for the day while letting digestion settle.
(2) Keep the amount small. The point of the charm isn't to get full. A single slice still carries the luck. A small amount means a smaller digestive load.
(3) If you must eat it on the morning of, keep it small and leave time before the start. Keep Chapter 3's "finish an hour before," but stricter.
Weigh "the heaviness of digestion" against "the lift in mood," and choose for yourself with the reasons in hand. You may eat it, or not. That's the heart of this column's conclusion.
And here too, the outcome depends on your body. If you know you're sensitive to greasy food, keep the amount even smaller.
7. What should you not eat before the exam?
These seven. Here is everything above folded into a cheat sheet of what not to do, so you can copy it for the day: the flip sides of the earlier chapters, one reasoned line each.
- Unfamiliar new food → The risk of stomach trouble isn't worth what you'd gain.
- Raw food (sashimi, raw oysters, etc.) → Losing the whole exam to food poisoning is a bad trade.
- Overeating / fullness → Blood flow goes to digestion; drowsiness and heaviness dull your morning edge.
- Skipping breakfast (going in empty) → Low blood sugar leaves you foggy; focus won't start up.
- Bingeing on sweets → The blood-sugar spike-then-crash tends to make you sleepier instead.
- A lot of caffeine you don't usually drink → Palpitations, frequent restroom trips, and other unfamiliar reactions.
- A heavy fried meal right before → Fat makes digestion heavy and keeps blood flow from your head.
Avoid just these seven and you'll prevent nearly all the big accidents. Put another way, anything else you can choose by mood. Narrow down "what to avoid," and every other choice becomes free.
In closing: there's no one right answer for food. The difference is whether you have a way to decide
There's no one right answer for food. The choice that's light on the body (digestion) and the choice that lifts the mind (mood) sometimes collide. Tonkatsu is the symbol of it. There's no textbook answer for how much heaviness to accept against the lift of carrying "I'll win."
But if, when they collide, you can decide for yourself how much of each to take, with the reasons in hand, that becomes the right answer for you that day. You may eat the tonkatsu, or not. The difference isn't whether you ate it. It's whether you have a way to decide.
The heaviness of digestion, the swing of blood sugar, the reason to choose the familiar, the reason to avoid raw food, how to make caffeine and water work: hold this map and you can evaluate the plate in front of you yourself. That becomes your weapon on the day.
passed.jp has "passing" in its name. I hope the version of you who shows up on exam day gets to put out everything you've got. Whatever you eat, may you reach your seat with a light body and a settled mind.
(To say it once more: what I've touched on here about food and nutrition is general, not medical advice. Bodies, conditions, and allergies vary, so if anything worries you, please consult a professional.)
FAQ
Q. Can I eat tonkatsu the day before the exam? A. Yes. Have it the night before rather than right before the exam, and keep the amount small. The heavy digestion of fried food matters less the more time there is before the exam, and a small portion the night before settles more or less by morning, leaving mainly the mood benefit for the day.
Q. By when should I finish breakfast on exam day? A. At least an hour before the exam starts. Right after eating, blood flow goes to digestion and your head works less well, so work backward so that the peak of digestion has passed by start time.
Q. What if nerves make it hard to eat breakfast? A. Get something in anyway; a small amount is fine. Going in on an empty stomach tends to leave you foggy from low blood sugar, and zero versus a little makes a real difference in your start.
Q. What should I eat during breaks between sections? A. Keep it light: a square of chocolate, a banana, or a small rice ball. Avoid bingeing on sweets, since the blood-sugar spike and crash tend to make you sleepier instead.
Q. I don't usually drink caffeine. Should I take some on exam day? A. Don't take a lot just for the exam. A body unused to caffeine can react with palpitations or frequent restroom trips, and the exam itself is a gamble of a place to try it for the first time.
