Proteins: All About These Essential Nutrients
Protein is a macronutrient and plays many essential roles. For iron health and increased energy, here's how to adapt your diet with protein, according to your age. Decoding in this article.
What are proteins?
Proteins are the main structural components of all cells in the human body.
Proteins are chains of amino acids that can be included in the composition:
from the skin;
Proteins are also the basis of many hormones, enzymes, and antibodies and are essential for tissue growth, repair, and defense in the human body.
Proteins have many properties, including:
macronutrients the amount necessary for life;
consisting of amino acids, essential or not, that determine the quality of the protein;
In food, there are animal proteins and vegetable proteins;
It has many roles in the body (enzyme, transport, tissue structure, etc.);
In fact, proteins need to change over the course of our lives.
Why do you eat foods rich in protein?
The role of energy
Protein provides energy, or 4 calories per gram. Like fats and carbohydrates, proteins are essential nutrients for the body.
C-reactive protein, a marker of inflammation
C-reactive protein (or CRP) is a protein made by the liver during inflammation.
The CRP test is very common during a blood test, it allows you to know if the body is having an attack or not.
Sources of essential amino acids
There are more than 20 natural amino acids found in dietary proteins.
Nine important amino acids that the body cannot manufacture. So it must be obtained through food.
Other amino acids are not essential because the body can produce them.
Proteins are involved in cell renewal, particularly in muscle tissue, skin and bone.
Proteins play many different roles in metabolism.
Some proteins are digestive enzymes that allow food particles to be absorbed, others form antibodies and allow the body to defend itself against external aggressions.
Finally, proteins are also involved in the formation of hemoglobin and some hormones.
20 high protein foods
The main sources of protein are products of animal origin (meat, fish, eggs, dairy products).
Certain foods such as legumes, nuts, seeds and grain products are excellent sources of plant protein.
Finally, some vegetables that are rich in protein also help cover the needs of the body.
There is not enough scientific data to support an elevation of ANC in physically active people.
On the other hand, since the type, intensity, duration, and frequency of exercise affect the body's use of proteins, protein intake over ANC is often recommended for highly active athletes (intense training every day).
Here are the recommended amounts:
Endurance athletes: 1.2 to 1.4 g/kg/day;
Strength athletes: 1.2 to 1.7 g/kg/day;
Healthy adults can safely consume up to 25% of their total calories as protein.
In France, individuals consume on average about 17% of their calories in the form of protein.
Animal proteins (meat, dairy products, eggs) are complete proteins, that is, they contain all the amino acids necessary for the growth and maintenance of the body.
On the other hand, plant proteins do not contain all the amino acids in sufficient amounts to make them complete proteins. However, soybeans are an exception to this rule and contain all the essential amino acids.
To supplement vegetable proteins, there are several options:
combination of vegetable protein and animal protein (for example, chili con carne);
combination of legumes (beans, lentils, chickpeas) and cereal products (for example, couscous and chickpea salad);
Mix legumes and oilseeds (for example, lentil-almond salad).
It has long been believed that it is necessary to make these associations in the same meal to ensure complementarity.
Recently, it has been shown that if complementary foods are eaten within a 24-hour period, the benefits of complete protein are present.
However, pregnant women should make these nutritional combinations at the same meal.
There are many diets that contain protein, and their indications are multiple.
In particular, increasing protein intake can be recommended to combat nutritional deficiencies or against malabsorption phenomena.
Likewise, for athletes, protein intake around bodybuilding sessions may be recommended to promote muscle mass growth.
These supplements can be made naturally through food or with the help of protein powders and other specialized supplements.
There are also protein diets for weight loss. However, they have not yet proven their value in the long run.
Whatever your condition and before increasing your protein intake, it is recommended that you consult a nutritionist. In fact, this is not without consequences.
harmful effects of proteins
Consequences of protein deficiency
Adequate protein intake should be provided daily to prevent protein-energy malnutrition.
Protein deficiency is very rare in industrialized countries, but it can occur in hospitals in people with disease as well as in the elderly.
On the other hand, in developing countries, there are two types of protein-energy malnutrition in developing countries and it causes the death of nearly 6 million children every year.
Protein deficiency has negative effects on all organs and systems of the body such as the brain, brain function, immune system and kidney function.
Signs associated with a protein deficiency are edema (fluid retention or swelling), decreased muscle mass, dull skin, and fine, brittle hair.
The risk of excessive protein intake from food is minimal.
However, some scientific studies of high-protein diets have shown an increase in digestive disorders or an increased risk of osteoporosis or kidney stones.
On the other hand, the most recent data indicates that protein intake is not associated with calcium loss from bone or with other negative effects on bone health.
Some high protein diets are often very high in animal protein and therefore high in saturated fat as well. It is therefore not surprising to see in the literature the relationship between consumption of red meat and high-fat dairy products, cardiovascular disease, and certain types of cancer.
People with chronic kidney disease and some genetic disorders should constantly evaluate their protein intake and should work with a dietitian to achieve this.
Protein interactions with other nutrients
The interactions between proteins and other nutrients are very numerous.
For example, they are responsible for transporting the smallest nutrients in and out of the cells of the body. In this sense, it can be said that an optimal nutritional state is necessary for the proper functioning of the whole organism.
Chemical properties of proteins
Proteins are the essential nutrients for all living things. Amino acids linked to each other by peptide bonds form polypeptide chains. These polypeptide chains arranged together, in turn, form proteins.
Protein chains are synthesized within the cell itself, in ribosomes. The sequence of amino acids, called the sequence, will determine their structure and function. All amino acids (except proline) consist of a carboxylic acid, an essential amine, and a side chain.
There are 22 proteinogenic amino acids, 9 of which are called essential, which the body cannot manufacture.
Protein electrophoresis is a method of protein analysis mainly used in medicine to study blood plasma. Allows analysis through a simple blood test, the level of various proteins present in the body.
Thus, it is possible to measure albumin, the rate of which indicates malnutrition or certain diseases of the liver or kidneys.
Proteins were discovered in 1835 in the Netherlands by chemist J. J. Mulder.
The name protein comes from the Greek word "protos" which means first, in the basic sense.
Since then and over the centuries, scientists have not ceased to highlight the multiple roles of proteins in the human body.