Blood sugar fluctuations change based on the 'quality' and 'way of eating' rather than the 'amount' of carbohydrates

I am using a blood glucose sensor and a ketone sensor to observe how my body reacts to my daily meals.

This time, I will discuss the changes in blood glucose and ketone levels when returning to a so-called "normal diet".

Because I had a very high-carbohydrate meal the previous night, my blood glucose levels were a bit erratic from the middle of the night through the morning.
As of the morning, my blood glucose was around 100. Ketone levels were almost zero.

I really felt that if I consume a lot of carbohydrates the day before, the effects remain until the next morning.

(5/26) Breakfast: Even when eating white rice, my blood glucose was surprisingly stable

Breakfast is quite simple.

* Atka mackerel
* Miso soup
* Cabbage
* White rice
* 7g of MCT oil C8

Due to the effects of the high carbohydrate intake from the previous day, my morning ketone levels were zero.
Since I ate white rice, I thought my blood glucose would easily rise in the morning, but in reality, it did not rise that much.
The increase was about 20 to 30.
For me, this is well within the acceptable range.
The way my blood glucose rose was not sharp; it felt like it rose slowly and returned slowly.
I think that even with the same carbohydrates, it changes significantly depending on food combinations and how you eat.

Lunch: You really have to be careful with company bento-style menus

Lunch was a meal like a bento box from the company.

* Japanese-style hamburger steak
* White rice
* Grilled eggplant
* 7g of MCT oil C8/C10

The Japanese-style hamburger steak looked normal, but it was actually a bit sweet when I ate it.
The carbohydrates in the sauce and seasonings probably don't suit me.
My blood glucose before the meal was around 100.
After the meal, it rose to a little over 140.
The increase was about 40.
Looking only at the numbers, it is not extremely bad, but looking at the graph, the way it rose was somewhat sharp.
My ideal is for blood glucose to rise like a gentle slope and return gently.
This time, it was a bit of a spike.
However, there were some good points.
About an hour after the meal, my blood glucose returned properly, and it did not drop too low like hypoglycemia afterward.

" It rose, but the return was not bad "

Dinner: Even with yakiniku, my blood glucose did not fluctuate significantly depending on how I ate

I ate dinner around 8:00 PM.

* Yakiniku kalbi
* Cabbage
* Cucumber
* Sesame tofu
* King oyster mushroom
* Japanese yam
* Brown rice
* Flaxseed oil
* 7g of MCT oil C8

The kalbi had a sweet sauce on it, so I thought my blood glucose would rise.
There was also some Japanese yam, and I ate brown rice.

However, this time I was conscious of how I ate.

First, the vegetables.
Next, the protein like the meat.
Finally, the brown rice.

This is what is called veggie-first.

As a result, my blood glucose did not rise as much as I thought.
The increase was about 30.

I had an image that yakiniku would disrupt blood glucose, but this time it did not become such a big spike.
However, perhaps because it was night, after it returned once after the meal, there was some movement of rising and falling a little.
Even so, it eventually settled down.

Carbohydrates have an 'aftertaste'

When wearing a blood glucose sensor, you can see the difference in 'quality' not just the 'amount' of carbohydrates.

What I felt in particular is that
the way blood glucose moves is different between starch-based carbohydrates like white rice and brown rice, and
things that use sweets, sweet sauces, and refined sugar.

Starch-based foods like white rice cause blood glucose to rise after a meal.
But after it rises, it returns properly, and after that, it is relatively easy to stabilize.

For example, even if it rises from 100 to 140, it returns to around 100 and settles down afterward.

On the other hand, things with a lot of sweets, sweet sauces, and refined sugar rise sharply.
And even after it drops, it rises and falls again.

Looking at the blood glucose graph, I truly feel it has a 'bad aftertaste'.

Even with the same carbohydrates, the way they enter the body is different.
This was a part that was difficult to understand just by feeling if I wasn't wearing a sensor.

Ketone levels are almost zero. My body was in a state of using carbohydrates

On this day, ketone levels remained at almost zero.

Because I had consumed high carbohydrates the previous day, I think my body was still in a state of using carbohydrates as energy.
However, as I adjusted my meal content, my blood glucose gradually became calmer.
If I reduce carbohydrates from here, ketone bodies should appear again.

(5/27) The reason why blood glucose is likely to rise at lunch

~Eating out, company bento boxes, and rice bowls definitely raise blood glucose~

In the previous normal diet, there were no major problems in the morning and evening.
However, there was a tendency for blood glucose to rise easily at lunch.
I feel that I need to be careful, especially with meals eaten at the company and menus for eating out.

Breakfast: Blood glucose is stable even with mackerel and white rice

* Mackerel
* Konjac
* Miso soup
* Cabbage
* Ground chicken
* White rice

I was also conscious of how I ate breakfast.
As a result, the rise in blood glucose was about 30.
It was not a sharp rise, and there was no particular problem with the way it dropped.
I learned that even if you eat white rice in the morning, if the food combination is good, blood glucose will not be disrupted that much.

Lunch: Spike with pork kimchi rice bowl

The problem was lunch.
On this day, I chose a pork kimchi rice bowl at the company.
Actually, there was a mackerel menu, but I had already eaten mackerel in the morning, so I didn't want to repeat it and chose pork kimchi.
Even though I made the white rice very small, it led to a rise in blood glucose.
I think there would have been few problems if it were just pork.
But rice bowls and seasoned menus often contain carbohydrates in the sauce and seasonings.

When I actually ate it, the taste was indeed sweet.
Looking at the blood glucose, it was definitely spiking.
The increase was about 50.
The return was not that bad, but I felt that if I choose eating out or rice bowl types for lunch, blood glucose is likely to rise.
Eating out and company meals have limited options.
That is precisely why what you choose is very important.

Blood glucose did not rise with protein after muscle training

I went to the gym in the evening.
Before muscle training, I intentionally did not replenish carbohydrates.
I went to training with just bone broth.
During muscle training, my blood glucose rose a little.
This is probably due to the influence of adrenaline.
Because the body needs energy during exercise, sugar can be released from the liver, causing blood glucose to rise.
However, the rise was not large, and I had the impression that it was being used properly during muscle training.
I drank chocolate-flavored protein after training, but my blood glucose hardly rose.

Late-night snack: Blood glucose is surprisingly stable even at a late hour

After muscle training, I actually wanted to eat dinner early, but there was a wait for equipment at the gym, so it became a little late.
After returning home, I had dinner at a late hour.

* Only the inside of the pork fillet cutlet
* Chicken
* Lettuce
* Carrot
* Potato
* Cucumber
* Vinegared chikuwa
* Brown rice
* Spicy mustard greens with cod roe

I removed the breading from the pork fillet cutlet and ate only the inside.
The breading has a lot of carbohydrates and oil, so I avoided it this time.
As for the amount of food at night, it was a little more than usual.
Even so, the rise in blood glucose was about 23.
After that, it did not fluctuate significantly and remained almost flat.
This dinner was clearly more stable than the pork kimchi rice bowl at lunch.

Ketone bodies still hardly appear

Regarding ketone bodies, they hardly appeared on this day either.
I was taking MCT oil with each meal, but even if they appeared, it was about 0.1 to 0.2.
It was about 0.3 when I went to bed at night.
I think the effects of the high-carbohydrate, high-fat meals from up to two days ago are still remaining.
Unless I use up the carbohydrates properly and the glycogen in the body decreases to some extent, ketone bodies will not appear properly.

Summary: Returning to a normal diet stabilizes blood glucose levels significantly

What I felt during this experiment is that when you return to a normal diet, the movement of blood glucose levels becomes quite stable.

However, be careful with lunch.
* Rice bowls (donburi)
* Sweet sauces
* Seasoned meat
* Eating out / Company bento boxes
* Processed side dishes

These items may contain more carbohydrates than they appear to.
On the other hand, starchy foods like white rice or brown rice can sometimes be surprisingly stable depending on how you eat them or what you combine them with.
Of course, if the amount of carbohydrates is high, your levels will rise.
However, when looking at the way they rise, the way they return to baseline, and the stability afterward, there is a significant difference depending on the quality of the carbohydrates.

When you wear a blood glucose sensor, you can see not just the post-meal numbers, but the 'habits' of your body's reactions.

By knowing the habits of your own body's reactions, you can improve your eating habits!

Next time: Blood glucose sensors and ketone bodies ~Spring 2026 Series~
This will be the final installment.
It turned out to be a conclusion that makes you wonder, 'Can that really happen?' so please look forward to it!