Our body has the possibility of using the energy supplied directly, storing it and retrieving it when necessary. What he does depends on our calorie balance. So whether our calorie intake is larger or smaller than our calorie requirement. See article: "Calculate Your Calorie Demand"
Energy content of the nutrients
Our body draws energy from the three macronutrients:
These nutrients have different amounts of energy. Energy is specified in the unit of measurement kilocalorie (kcal) or according to the internationally standardized unit of measurement in kilojoule (kJ). Below is the energy that our bodies each get from one gram of the macronutrients.
Macronutrient kilocalories per g*
carbohydrates 4.1 kcal (17kj)
protein 4.1 kcal (17kj)
fat 9.3 kcal (39kj)
Dietary fiber 2 kcal (8kj)
alcohol 7.1 kcal (30kj)
* One kilocalorie is the amount of energy required to heat a liter of water from 14.5 to 15.5 degrees Celsius (1 kcal = 1000 calories). One joule corresponds to the energy required to move an object with the force of one newton by one meter (1 kJ = 1000 joules)
Healthy macronutrient distribution?
Now we know which macronutrients provide how many calories, but how much of it should we eat now? There is no macronutrient distribution recognized as generally healthy. The individual physical conditions and nutritional goals of the people are too individual for this. The German Nutrition Society (DGE) sees a meaningful (and certainly true for 80% of people) macronutrient distribution as follows:
- 50–60% of the recommended total energy should be supplied in the form of carbohydrates (55% on average).
- 30-35% of the recommended total energy should be supplied in the form of fats (30% on average).
- 10-15% of the total recommended energy should be in the form of protein (15% on average).
This macronutrient distribution mainly supplies our body with carbohydrates, which we need as fuel to maintain our body functions. It contains enough fats to make important metabolic processes and the hormone balance work well and enough proteins that serve as building material for our body.
Their quality is much more important than the quantitative distribution of macronutrients. For example, Complex carbohydrates from whole grains are healthier than simple carbohydrates from white flour products. Vegetable fat, like vegetable protein, is healthier. as fat and protein of animal origin. This is summarized very nicely in the book "The Nutritional Compass" by Bas Kast.
Calculate calories in food
Okay, now we know a sensible distribution of the macronutrients. But how do we know how much of our food contains the respective macronutrient? To calculate this we need a nutritional table. It lists not only the macronutrient / but also the micronutrient distribution for all common foods. The indication of the micronutrients is important in order to be able to assess how high the quality of the food and the marconutrients contained therein is. I enjoy working with the Heseker nutritional table.
Using a portion of muesli as an example, we want to calculate the energy and nutrient content of the oatmeal. Here is an extract from the recipe:
- 2 tablespoons of pithy oatmeal, 20 g
- 1 small apple, 100g
The nutritional value tables generally contain energy, protein, fat and carbohydrate content for 100 g of food. In addition, there is also information about other ingredients. Some tables also refer to the nutritional information on certain portion sizes of the food, this is then marked separately.
Step 1: Using a nutritional table, the information for energy, protein, fat and carbohydrates is transferred for 100 g of food.
100 g oatmeal - 348 kcal - 13g protein - 7g fat - 59g carbohydrates
20 g oatmeal - 69.6kcal - 2.6g protein - 1,4g fat - 11,8g carbohydrates
Step 2: The nutritional information and the energy content are to be converted to the amount of food specified in the recipe. With 20g oatmeal and a reference value in the nutritional table of 100g, the following conversion factor results: 20: 100 = 0.2. Now we can e.g. convert the energy content of 100g oatmeal from 348 kcal with the conversion factor 0.2 to the portion size according to the recipe of 20g oatmeal, e.g. for the calories 348 x 0.2 = 96.6.
Step 3: The partial quantity must now also be calculated for all other foods. To determine the total amount of energy and the nutrient content, the details of the various foods from the recipe are added.
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