Protein – one of the basic ingredients necessary for the proper functioning of the body. It has become extremely popular among athletes, but also among people seeking to reduce weight, thanks to the famous diet of Dr. Dukan. A lot of people say that they know everything about the protein – it slows down, helps build a muscular figure, does not harm the body. But is all this the truth? Does the protein still have a different side? To answer this question, it is worth looking at it from scratch. Let’s get to know the most important information about this ingredient.
Proteins – human, of animal or vegetable origin – as complex compounds are composed of subunits, which in the case of proteins are amino acids. They determine the biological value of the protein, and delivered in the right quantities – they allow the body to synthesize all the proteins that it needs to function.
Amino acids can be divided into two groups
– so-called endogenous, which the body is able to create itself;
– so-called exogenous, called essential, which must be provided to the body along with food, and include isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.
There is also a third group of amino acids – conditionally necessary, which include serine and arginine, whose synthesis in the body is insufficient in special cases, e.g. in the period of rapid growth, disease, stress, and also histidine, which is not produced by the child’s body. This means that in these specific situations should be additionally delivered to the body with food.
It is the presence of amino acids and their appropriate proportion in the food protein that affects its biological value and the degree of use for the synthesis of body proteins. Thus, the quality of food protein depends mainly on
– content of essential amino acids;
– proportions between exogenous amino acids, which should be close to the ratio found in body proteins.
It is generally established that proteins of animal origin are high-value proteins because they provide all the essential amino acids. In addition, it is worth knowing that WHO experts recognized that the reference protein – the closest to the composition of body proteins – is egg white for an adult and infant milk protein for infants. This means that proteins from these sources are best used for building and other purposes of these compounds in the body.
Mostly, the proteins of plant origin are characterized by much lower biological value. For this reason, in the case of vegetarian and vegan diets, it is important to properly arrange products that together provide the body with essential amino acids in appropriate quantities (eg a combination of cereal products with legumes that complement each other in terms of amino acid structure). In other words – the diversity of consumed meals is important, providing proteins from various sources that will provide the supply of all essential amino acids on the principle of complementation.
The role of protein in the body
The proteins in our body meet versatile functions. Their basic task is to participate in the growth of the organism and maintain its general functioning. Their importance concerns aspects
– building blocks, because all our tissues are built of proteins – muscles, bones, nerves, internal organs, body fluids or skin, hair and nails;
– regenerative – they take part in tissue renewal, strengthen the walls of the arteries and help in wound healing, allow hair and nails to grow, regenerate exfoliated epidermis and also the epithelium of the digestive tract,
immune – antibodies fighting against any bacteria and viruses are proteins (!);
– transport – proteins transfer substances in our body, eg transport of iron or fats, sugars, etc .;
In addition, the role of proteins in the construction of some compounds involved in any changes taking place in the body is important.
And so – proteins are included
– some hormones, e.g. insulin, regulating blood sugar or thyroxine, which regulates metabolism and body temperature;
– enzymes – compounds that give rise to all chemical changes and without which our body’s functioning would not be possible.
Protein sources in food
As mentioned before, proteins are divided into those of animal and vegetable origin. Animal proteins, the so-called wholesome ones, are able to provide the body with essential amino acids, which it is not able to produce itself, and in addition – they do it in proportions similar to the composition of body proteins.
From this side of the protein can be obtained from
– eggs, whose protein has been recognized as a model;
– milk and its products;
– meat and its products (although the healthiest choice is lean, white meat);
– fish – fatty and white meat, because these two kinds are the best source of protein (eg salmon, sardine, mackerel, herring, cod, trout).
Plant-derived proteins are called deficient foods because they are characterized by a lack of at least one exogenous amino acid in their composition.
Of these, proteins with the highest biological value are characterized by
– legume seeds (eg lentils, chickpeas, beans, soybeans, tofu);
nuts and seeds (almonds, walnuts, hazelnuts, pecans, brazilian, cashews, sunflower, pumpkin, sesame, linseed);
– quinoa, which to some extent acts as a grain product, but is much richer in protein than other cereals, and most importantly – has all the essential amino acids.
It is worth remembering that the most favorable solution is to combine products of both animal and vegetable origin. Because although animal protein is much better absorbed than vegetable, it does not have fiber, which plays such an important role in the operation of our digestive system. The best solution, therefore, is as always in a rational and healthy menu.
This does not mean, however, that people who practice a vegetarian or vegan diet are not able to provide the body with the right amount of wholesome protein. Certainly in their case the task is a bit more difficult, because it requires combining products that will complement each other’s amino acids, but it is not impossible. Also, building muscle mass on this type of diet will be heavier, but with the right selection of products – although a bit longer, it is 100% possible.
High protein diet and hazards resulting from it
Although the functions of proteins in our body are innumerable, and without their participation our system would not be able to function – as in any case there are certain limits.
High protein diet, so popular among athletes, although it is to stimulate metabolism and help on the way to the dream figure, it’s too long
and intensely carried out can contribute to unwanted side effects
– urinary tract disorders (eg, kidney stones);
– liver disease;
– acidification of the body;
– increase in the so-called bad cholesterol.
Protein delivery is undoubtedly necessary for functioning and health of the body, in the case of athletes – it is necessary to increase the supply of this ingredient. You can not deny the protein diet many advantages – it helps to build muscle mass or reduce weight, but too rigorously conducted can turn against us in very serious health complications.
As you can see, proteins – along with carbohydrates, fats and minerals – must be delivered to our bodies in reasonable amounts, adapted to the current needs and the state of our system. Properly conducted protein diet will help in obtaining the dream look of our figure, however, it is not worth doing anything by force to accelerate such desired effects. Because then, after a short joy of the obtained goal, we will face the effects of our irrational action.