There is no meaning in simply calculating calories


  1. The Human body is not that simple
  2. Why a simple daily calorie intake calculation is meaningless

1.The human body is not that simple

Here, I want to show you that “comparing the daily intake of calories and consumed calories to calculate how many calories you stored (get fat)” doesn't really have a meaning.

Often on TV, nutritionist or doctor say to those who gained weight “you have 120kcal over the line per day meaning 3,600kcal per month. This is 0.5kg body fat. So if you keep like this for 4 month, it will turn into 2kg of body fat” (based on a calculation of 1kg of body fat =7200kcal).

Calculating the daily calorie intake is useful as a rough standard of “average necessary energy” for cooking on a large scale such as in a school or retirement home.

However, it is meaningless to use it as a standard for individuals and for a sense of “overweight / obesity”, that’s another problem.

2.Why a simple daily calorie intake calculation is meaningless

  Though there are several reasons, I would like to explain the following 3 as my own reasons.

(1)  It's the intestinal starvation mechanism that causes your Base Weight to go up.  

In this case, an absolute amount of calories won’t directly cause a change. It's the B mechanism that people gain weight by eating a lot.
【Related article】
2 meanings of the phrase "gaining weight"

(2) There is no meaning in comparing the amount we eat (calorie intake) and consumed calories

Not only in calories but in all nutrition, our body can’t digest/absorb everything we eat and digestion ability/absorption ability differs by each person.
Also, a calorie label on food products are calculated based on “combustion heat” but actual reaction in our body is chemical. So there is little meaning to calculate displayed calories or a nutrition index.


What needs to be compared here is “the internal intake amount” which means the absorbed amount in the intestines.

At least in my case, “low absorption ability” was the hurdle for me to gain weight and it still is. Those who can't gain weight even with eating, it's not that they have good metabolism (*referece1), but they have a limit that can be taken due to the absorption ability.

In Japan, people sometimes say “it’s inefficient that you eat a lot but can’t get fat” but it really is, the truth, it’s inefficient. If you try to compensate this by intake volume, the absorption rate will decrease relatively, so it just won’t work [refer to (3)].

On the other hand, there is an expression “a body that gets fat by only drinking water” in Japan. It expresses those who gain weight even though they eat very little.

Of course, “water” is an exaggeration but it’s true that their tendency to get fat is really that high. This is another example that expresses the “absorption ability”.

(3)Absorption ability is not fixed but improves by hunger or exercise.

When we are hungry for some time or after doing sports, our absorption ability(rate and absorption amount) improves and when we eat even though we are not feeling hungry, the absorption rate decreases relatively.

The Intestines do not absorb at the same pace, but controls the absorption rate in order to maintain present condition. It’s much in the same way as the body temperature is always around 98.6°F (or 36℃). (Also, it has been proved through experiments that the less calorie intake there is, the less basal metabolic expenditure there becomes.)

For example, even if you skip your lunch and eat nothing till dinner, there is still your breakfast in your Intestines. Your Intestines are working hard to take nutrition out of what is left. If there is no nutrition anymore in the intestines, the body will break down protein or body fat temporarily.

However, the more hunger continues, the higher the absorption ability after the dinner (and the body fat that was used up previously will recover soon).

That is to say, the body is working in a sense to maintain constancy of that person. So even if you calculate your reduced calories everyday, the body fat won’t decrease at the same pace.


If we change our meals from steak & roll (about 850kcal) to a hot dog (one hot dog: 450kcal), the difference by a simple calculation is -400kcal. But it’s only the number and even if you calculate it for a month, there is no meaning in it.

Rather it might be the intestinal starvation mechanism occurring between lunch and dinner that is causing the person to get fat.

▽Let’s see another example of thin person who wants to gain weight and therefore eats a lot.
If he keeps eating even though he isn’t hungry, his absorption rate will decrease relatively (of course there are differences in each person). Consider this, after we eat food, it digests for 3 to 5 hours and finally when it is starting to be absorbed, another food comes into stomach. So the body will perceive that “here comes some more food... we can simply absorb from the new food”.

That explains the old Japanese saying “hunger is the best nutrition”. What improves the absorption ability are hunger and exercise (especially a loading motion to the muscles).

<reference 1>

October 2016, Professor Osumi’s “Autophagy”(taken from the Greek meaning “cell’s self eating mechanism”) won the Nobel Prize in Physiology and Medicine.

It clarified, in the case when there is no nutrition in the cell as such as in long starvation, how unnecessary protein is broken down into amino-acid and reused as a nutrition source.

That is to say, there is no waste in the human (creature) body as it will recycle even unnecessary protein. Logically saying “thin people have good metabolism / easy to break down fat” is a ridiculous theory that neglects the mystery of the human body.

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