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Diet [Part 3] Adjust calorie intake with three major nutrients

Since I was able to calculate the “daily calorie consumption” in diet [part 2], I will explain how to calculate the calorie intake in diet [part 3].

To calculate calorie intake, adjust the intake (diet) based on the three major nutrients of protein, fat, and carbohydrate.

It is called “PFC balance” using the acronyms of the three major nutrients.

Three major nutrients

Basic numbers you want to keep down (PFC energy)

To calculate calorie intake (eating amount), you need to know the amount of energy relative to the weight of nutrients.

P: Protein = 4kcal / g
F: Fat = 9kcal / g
C: Carbohydrate = 4kcal / g

Calorie intake calculation procedure

  1. Know the daily calorie consumption: Calculation result in diet [Part 2].

  2. Goal setting: Determine the duration of your diet and the amount of fat you will lose in a month.

  3. Set the calories you can consume in a day: Determine the calories you want to lose, taking care not to fall below your basal metabolism.

  4. Adjust PFC balance: Adjust calorie intake and nutritional balance based on the energy possessed by PFC.

  5. Monitoring and readjustment of PFC balance: Regularly monitor the progress and readjust the PFC balance.

Setting diet goals

It’s a good idea to use your body fat percentage as a guide when setting your goals.

[Example of goal setting]
Calculated with the goal of losing 10 kg of fat in 5 months for a person with a body weight of 70 kg and a body fat percentage of 25%.

Understanding the current situation and goals

Current status

the goal

Body weight

70kg 60kg

body fat percentage

25.0% 12.5%

Body fat mass

17.5kg(70kg×0.25) 7.5kg(60kg×0.125)

* To burn 1 kg of fat, about 7,200 kcal of energy is required.

If you want to lose 10 kg of fat in 5 months, your goal is 2 kg per month.

Converting 2 kg (14,400 kcal) per month into daily calories is 480 kcal (14,400 ÷ 30 days).

In other words, the specific number to consume less calories or consume more calories per day is 480 kcal per day.

(Daily calorie intake) = (Daily calorie consumption) -480 kcal If you set it to, you will lose 2 kg a month.
* Daily calorie consumption = basal metabolism (BMR) x life intensity index (calculation of diet [2])

The true meaning of eating and losing weight

Athletes often say “eat and lose weight”, which means that you should burn calories by training as much as you eat.

When you train, your muscles develop, your basal metabolism rises, and your body fat burns more easily.

What you should never do on a diet is to lower your calorie intake than your basal metabolism.

Be aware that the wrong diet, which just loses weight, can lead to a shabby body shape and adverse effects on internal organs and brain.

Goal setting below (basal metabolism = 370 + 21.6 x lean body mass) introduced in diet [Part 2] is NG!

PFC balance

“PFC balance” refers to the composition ratio of the three major nutrients to the calorie intake.

The composition ratio (PFC balance) “4: 2: 4” is the ratio of calorie intake of the three major nutrients.
“P (protein) = 4 (kcal)”
“F (lipid) = 2 (kcal)”
“C (carbohydrate) = 4 (kcal)”

Food intake is the result of converting this composition ratio into weight (grams).

Specific example of PFC balance “4: 2: 4”

Calculation of PFC balance “4: 2: 4” assuming that the target calorie intake is 2,000 kcal.


Daily intake : P(protein)=200g、F(fat)=45g、C(carbohydrate)=200g

In this way, we will specifically calculate the amount of food we eat each day.

It is important to determine the value first F (fat)

The ratio of F (fat) that is first determined in PFC is 10% to 20%.

Lipids may seem like natural enemies in a diet diet, but lipids are essential nutrients for cell membranes and hormones.

In particular, α-linolenic acid and linoleic acid require the intake of essential fatty acids (fatty acids that cannot be synthesized by the body).

Lipids give you a feeling of fullness when you are on a diet and help absorb fat-soluble vitamins. In addition, medium-chain fatty acids (MCT oil) contained in coconut oil, etc. are decomposed 4 to 5 times faster than general oil, and become energy in a short time.

Calculation example when the calorie intake is 2,000 kcal

Calculated with 10% to 20% of calorie intake


Approximate intake will be 22g-45g.

P (protein) that you want to take 1.5 to 2.0 times your lean body mass

The next decision is P (protein).

Some bodybuilders who want to build muscle consume more than 4.0 / 1,000g of lean body mass.

Since overdose has a risk of osteoporosis and burden on the kidneys, the general public should use 1.5 / 1,000g to 3.0 / 1,000g of lean body mass as a guide.

Protein is a collection of amino acids and is indispensable because it contains essential amino acids (amino acids that cannot be synthesized in the body).

The intake can be calculated by multiplying the lean body mass calculated in Diet [Part 2] from 1.5 / 1,000g to 3.0 / 1,000g.

C (carbohydrate) where intake timing is important

The final factor in the composition of PFC is C (carbohydrate).

The calculation method is the remaining calories after subtracting the “fat calories” and “protein calories” calculated earlier from the “daily calorie intake”.

Some lipids and proteins are said to be “essential” and can only be taken in the diet. Carbohydrates, on the other hand, are not essential, but they are important nutrients for the body.

Since the human body has a function to enter “energy saving mode” and reduce calories burned if the same diet is continued for a long period of time, it is recommended to occasionally change the balance between P and C to stimulate it.

Specific calculation example

The result is not as calculated easily, but the body fat percentage up to around 10% is a range that even ordinary people can easily do. 10% to 15% for men and 18% to 21% for women can be achieved by working patiently.

1. Setting goals

Suppose a person weighing 60 kg and having a body fat percentage of 25% loses 12 kg of fat in 6 months.

The target values ​​are a weight of 48 kg and a body fat percentage of 6.25%.

2. Calculation of target calorie intake

1. Calculate lean body mass.
Weight x ((100-body fat percentage) / 100) = 60 x ((100-25) / 100) = 45 kg

2. Calculate basal metabolism.
370 + 21.6 x lean body mass = 370 + 21.6 x 45 = 1,342 kcal

3. Calculate calories burned (assuming moderate life intensity)
Basal metabolism x life intensity index = 1,342 x 1.7 = 2,281 kcal

4. Calculate the fat calories to be dropped. (12 kg loss in 6 months, 2 kg loss in 1 month)
It takes about 7,200 kcal of energy to remove 1 kg of fat.
2kg per month is 14,400kcal = 480kcal per day (14,400 ÷ 30 days)

5. Calculate the target calorie intake
Consumed kcal-Fat to be dropped kcal = 2,281-480 ≒ 1,800 kcal

3. Adjustment of PFC balance

1. P (protein) intake (assumed to be twice lean body mass)
“Lean body mass” x 2 = 45 x 2 = 90 g (4 x 90 = 360 kcal)

2. F (fat) intake (assuming 20% ​​of calorie intake)
“Target calorie intake” x 0.2 = 1,800 x 0.2 = 360 kcal (360/9 = 40 g)

3. C (carbohydrate) intake
“Target calorie intake”-“P intake”-“F intake”
= 1,800-360-360 = 1,080kcal (1,080 / 4 = 270g)

【Calculation result】

How to lose 2 kg of fat every month for a person who weighs 60 kg and has a body fat percentage of 25% P = 90g, F = 40g, C = 270g per day.

This is just an example, so please adjust it yourself.

If you want to know the ingredients of food, you can easily search the “Food Database” of the Ministry of Education, Culture, Sports, Science and Technology.

It’s hard to calculate the calories in your diet every day. It takes a lot of work at first, but if you calculate it several times, you will be able to understand it by feeling, so please try to incorporate it.

This time, it was a method of adjusting calorie intake with the three major nutrients.

Diet series [Part 1] to [Part 5]
I have an article about the specific calculation method required for dieting, so please read it in order!

Diet [Part 1] Not weight loss! Remove fat
Diet [Part 2] Know the daily calorie consumption
Diet [Part 3] Adjust calorie intake with three major nutrients
Diet [Part 4] How to eat
Diet [Part 5] Prepare the intestinal environment