Caloric Content of the Diet: Why Do We Need Proteins and Fats

One of the most well-known ways to deal with an excess of light carbohydrates is through diets, most often with a significant calorie restriction of the diet. Fats and proteins are restricted. Let’s see if it’s right.

Each person needs a different amount of energy – it depends on weight, height, age, profession, habitual physical activity and many more nuances based on which the calorie content of the diet is calculated. Most people are familiar with the phrase “energy metabolism”, but not everyone knows what energy is spent in the body.

What Determines the Calorie Content of the Diet

When it comes to the caloric content of the diet, first of all, we mean proteins, fats and carbohydrates, which have a certain energy capacity. So, when burning 1 g of protein, 4 kcal is released, 1 g of carbohydrates – 4-4.2 kcal, 1 g of fat – 9 kcal. And at first glance, it is completely logical to limit fats because they are the most energy-intensive. And if you go through simple arithmetic calculations, you can decide that when you eat 100 g of protein, the body will receive 400 kcal. But everything is not so simple.

Whey Proteins are Needed, and at What Age is they Especially Important?

The role of protein as an energy source is insignificant. However, protein foods can also be a source of glucose (the main energy substrate), which is synthesized from certain amino acids. Proteins are the main building material of cells. 

Therefore, a sufficient amount of high-quality protein is fundamentally important in the nutrition of people of all ages since the body’s cells are constantly updated, and all enzymes, antibodies, hormones and other biologically active substances are also proteins.

It is worth considering that 4 kcal of clean energy is formed from 1 g of protein only under ideal conditions in a chemical laboratory. And if we talk about the protein obtained from food, then a huge amount of energy is required for its assimilation (digestion, absorption, transportation, etc.). 

You can even remain in some energy deficit when the protein goes through all these stages. The body will spend energy but will receive high-quality building material for cells.

Protein food is not completely digested (unlike instantly absorbed carbohydrates); therefore, in ordinary life, and not in a laboratory experiment, one cannot obtain 400 kcal of pure energy from 100 g of protein.

What Role Do Fats Play in Nutrition?

On the one hand, fats are a powerful energy carrier invented by nature; on the other hand, they serve as a kind of “gold reserve”. This means the body will use the fat reserve only in an emergency. The energy stored in adipose tissue is enough to last for several months. This is extremely important for survival in adverse conditions. For comparison: the supply of carbohydrates in an adult’s body is not enough even for a day.

Fats, like proteins, are not fully digested and require enough energy to digest. In addition, fats also act as one of the main structural components of our body: they are part of all cell membranes, without exception. The structure of cell membranes depends on which fats predominate in the diet and, accordingly, the quality of the work of each cell, which determines human health.

Excess and lack of fat (except artificially created, such as trans fats) can be harmful to health. One of the most striking examples of “fat imbalance” in modern nutrition is the deficiency of omega-3 polyunsaturated fatty acids (PUFAs) with an excess intake of omega-6 PUFAs. Omega-3 and omega-6 PUFAs act in the body in different directions, participating in the same processes.

Omega-3s provide plasticity to cell membranes (especially important for intensively working cells, such as neurons and heart muscle cells), and omega-6s have a greater effect on their rigidity. With a deficiency of omega-3, their place is taken by omega-6, which affects the performance of cells and the well-being of a person. In particular, omega-3 PUFA deficiency affects cognitive development, especially in childhood. 

In addition, omega-3s are involved in immune responses and inflammatory processes, reduce vascular tone and the risk of thrombosis, improve blood supply to organs and systems, and perform many other functions. 

At the same time, omega-6s are involved in the same processes but diametrically opposite. An adequate reflection of a sufficient amount of omega-3 PUFAs in the body is the omega-3 index (determined in almost any laboratory). A value of 8% or more is a good indicator of the body’s supply of omega-3 PUFAs.

“Sharply limiting fat intake is undesirable because, at the same time, the body receives a signal that hard times are coming, and protection is triggered – energy reserves are formed much more actively in adipose tissue,” says Daria Kinsht. 

“A study conducted by South Korean scientists confirmed that a sharp restriction of fat intake (less than 15% of the daily calorie intake) increases the risk of developing metabolic syndrome even if the intake of fat is balanced”. 

Natalya Kondakova supplements her colleague: “In this regard, I would like to say about low-fat products (most often dairy products), which are considered healthy and dietary. 

This is not entirely correct because when fat is removed, the taste and consistency of the product change, which must improve must improve. Most often, this is done just by adding carbohydrates. Secondly, the balance of other substances may be disturbed, and their absorption may suffer. For example, calcium and vitamin D. 

Thirdly, milk is one of the most balanced products invented by nature since it contains all the components (including fats) in an accessible, easily digestible form, which is also important.

The specialist adds that fat-free products appeared more due to the efforts of marketers than nutritionists.

How to Determine the Content of Various Substances in the Diet

Proteins, fats and carbohydrates are the main components of nutrition, but there is another very important but always noticeable component. We are talking about biologically active food micronutrients, without which a good metabolism is impossible. Vitamins and other micronutrients are necessary for many biochemical reactions in the body (including energy production) and protection against free radicals, bacteria and viruses.

Laboratory analysis of the content of most trace elements and vitamins in the blood makes it possible to assess how adequate their consumption level is. However, these methods are costly and require interpretation by specialist physicians. 

The analytical path, i.e., filling out questionnaires, can be chosen as a possible alternative. A good example of the implementation of this method is the free online service Fitcha-Nutrition from Siberian Wellness. Spending about 20 minutes on questions about nutritional habits can provide data on the content of about 60 different substances in the diet. 

The result of the answers is built on Fitcha-Nutrition algorithms, which are based on one of the complete databases on the content of chemicals in food.