Protein - an organic substance consisting of amino acids linked by a peptide bond. Proteins in the human body are formed from 20 specific amino acids, some of which are indispensable and must come from food.
The role of protein in the body
Proteins are a source of energy, one of the three most important components and building elements. First of all, building elements: approximately 2/3 of the protein that enters the body is used to build your own proteins, 1/3 is broken down to produce energy.
In the human body, these substances perform many different functions: these are enzymes, and building material (keratin, which makes up nails and hair - protein), and regulators of reactions in the body, and signal translators.
Proteins are in the membrane and inside the cell, catalyze and accelerate the chemical reactions that occur in the body.
In addition, they perform protective, transport and reserve, receptor and motor functions (a separate class of proteins provides the movement of leukocytes, muscle contraction, etc.). Of course, each task has its own type of protein, but they are all built from standard "bricks".
Complete and Defective Protein
Proteins do not accumulate in the body, so they must be regularly supplied from the outside. And here division into high-grade and defective proteins comes into play. Dietary protein sources give either one type of protein or another.
Full-fledged ones - those that have in their composition all 20 "bricks" of amino acids. Inferior ones are proteins that do not contain one or several necessary amino acids, or are present, but in too small a quantity. However, the body must necessarily receive from the outside 8 essential amino acids that it cannot synthesize itself. Hence the universal “race” for complete proteins (which contain everything, including these eight amino acids).
Sources of protein: animal and vegetable
The source of protein for humans is animals and plants. Both there and there are protein substances. The "official" opinion of modern experts says that every day you need to eat from 45 to 100 grams of protein. Animal meat is considered a good source of high-grade proteins, while plants , according to many experts, do not contain high-grade proteins.
The conclusion of the WHO working group says this: even with full vegetarianism, the body still receives all the necessary substances. Why? Because there is a mutual complement of amino acids from different dishes and components.
A well-planned vegetarian menu is a full-fledged one, it supplies everything that is needed to the body, in addition, it can even be therapeutic and dietary. According to studies conducted at the Max Planck Institute in Germany and the Carolina Institute in Sweden, enough vegetables, fruits and nuts contain complete protein. Thus, both vegetable protein and animal protein are suitable for nutrition.
Meat and semi-finished products from it
Animal protein can be obtained from the meat of mammals, birds, fish. Chickens, rabbits, cows, pigs, sheep, various sea and river fish are not processed sources of protein. Sausages, sausages, stew - if these products are natural and made in accordance with GOST, they also contain suitable protein.
Products with high quality protein - eggs and dairy products. Chicken eggs give an almost perfect protein, moreover they are digested very well. They have very few flaws, but they are not worth it in their raw form - heat treatment contributes to better absorption of nutrients and getting rid of germs.
Almost the same goes for dairy products. Whey proteins are absorbed very well, in terms of their amino acid composition they are the closest to the amino acid composition of human muscle tissue from all products. The main source of these proteins is whey, which is obtained in the production of rennet cheese.
Protein table "in products":
The protein myth
Until the end of the twentieth century, it was believed that only meat and products from it contain complete protein. On English-speaking resources, this opinion is called the "protein myth." However, it was subsequently proved that soybeans also contain all the essential amino acids.
Vegetable protein source
Among plants, a full-fledged source of protein is soy and products from it (for example, tofu). Also integral are the proteins of buckwheat, amaranth, cilantro and sowing hemp, as well as spirulina algae. And if amaranth, cilantro or hemp is difficult to find in these latitudes, then spirulina and its additives are generally available and are sold in pharmacies and health food stores.
In addition, plants with so-called defective proteins are also able to satisfy the need for protein. All you need is to combine them correctly.
For example, a table of proteins states that legumes and mushrooms are rich in isoleucine and lysine, and cereals and nuts are rich in tryptophan and sulfur-containing amino acids. By combining the various components, we end up with everything we need.
Milk protein
In the "golden age" of bodybuilding, many stars and champions of this sport drank fresh milk. The strongmen of that time called him the elixir of strength and drank several liters a day. Doctors agreed with them on this, prescribing dairy products as a medicine to their patients.
Nowadays, the sources of protein in the diet of athletes are industrially created additives. Scientists have learned to create highly nutritious and balanced mixtures in which whey protein is present in the most accessible form. Some athletes are still trying to drink milk - but since the general fear of bacteria is gaining momentum, they drink it boiled or pasteurized.
However, the method of the predecessors was good in the form in which they used it. Modern pasteurized, sterilized, processed many times milk has little in common with the product that Olympic weightlifting champion John Grimek loved.
Eggs
To date, whey protein is considered the most easily digestible for humans, but the protein of eggs is inferior to it quite a bit. This source of protein gives full-fledged "bricks" and is considered to be a reference - other proteins and products are evaluated in comparison with it.
This is one of the most useful products in bodybuilding and powerlifting. Plant protein and animal protein cannot compete with it in efficiency. Egg protein is actively used for the manufacture of food additives.
Eggs, like milk, can be consumed at any weight, during weight gain and during weight loss. Bodybuilders eat them in huge quantities - for example, Jay Cutler, four times Mr. Olympia, eats about 170 egg whites a week, he eats them twice a day.
Special sports nutrition
The usual sources of protein in food can be supplemented with special sports supplements, which are developed by the best scientists commissioned by the multimillion-dollar industry. These are specially developed complexes and supplements made according to the latest achievements in the field of nutrition and physiology.
The main protein base in sports supplements is casein or whey protein. The most serious difference between them is that casein protein is absorbed in the body for 5-6 hours, whey - 1.5-3 hours.
They are obtained in several different ways, having as a result different protein purity and the presence or absence of extraneous fats. However, the technology already allows you to get a fairly cheap and easily digestible protein that can be used not only by athletes, but also by “ordinary” people.
Artificial Proteins
The first artificial protein was created more than ten years ago, and during this time, scientists were able to get to the creation of complex structures. It can be expected that sooner or later products will appear on the market that can replace both meat and plants in this regard. Already created artificial "meat", which scientists grow on the basis of animal cells.
The source of protein "from the test tube" can suit everyone - both animal defenders and producers, but for this we must first reduce the cost of the process, since now it is too expensive for mass production. And the taste of a piece of food should also meet expectations.
Unfortunately, for vegetarians this method is not suitable - they still have to look for complete proteins in plants. However, in the near future this can also change - science is moving forward with enormous steps, and the creation of synthetic protein for wide sale is only a matter of time and demand.