Proper nutrition plays a major role in maintaining good human health. Proper nutritional use requires some knowledge about nutrients. Nutrients provide maintenance of life and perform many functions in the body:
- They are structural components of the body;
- Participate in chemical reactions during metabolism;
- Regulate the intake, distribution and release of various substances;
- Provide thermoregulation;
- Affect the taste and palatability of feed.
- Provide the body with energy.
6 main classes of nutrients
Water is an important component of nutrition. Every day, a certain amount of water is vital for the body to digest food, remove toxins and maintain normal body temperature. From a medical point of view, a loss of 7% of the total amount of water is a physiological catastrophe for a person.
The body’s need for water is about 2-2.5 liters per day.
Muscles contain the most water – its total content ranges from 50 to 70 percent, depending on age, sex and body type. Water can be contained either inside the cells (approximately 62% of the total) or outside the cells (approximately 38%). The average half-life of water that got there is 3 days.
Water is obtained through three channels:
- fluid intake (about 60 percent of total water consumption);
- food (about 30 percent of total water consumption);
- metabolic processes (about 10 percent of total water consumption).
Carbohydrates are substances that are the main source of energy the body to work. Some carbohydrates are poorly absorbed by the body. The simplest example of an energetically valuable carbohydrate is glucose and fructose.
Rich sources of carbohydrates: flour products (baking from whole-grain cereals, spaghetti, pasta, pizza), lentils, peas, soy, honey, jam, beans, fructose, food sugar.
Food and Nutrition Magazine reminds you that the bulk of carbohydrates (65-70% of the total) should be consumed in the form of polysaccharides (starch), 25-30% – simple and easily digestible carbohydrates (sugar, fructose, glucose) and 5% – dietary fiber.
Proteins are the main building material of the body, necessary for the formation of new muscle fibers, the restoration of injured and replacement of dead tissue in all organs. In addition, all enzymes, i.e. regulators of chemical processes in the body are also proteins. Large protein molecules are made up of smaller-sized amino acids, which are interconnected like links in one chain inside the protein. Some amino acids can only be ingested from outside with food – such amino acids are called essential. Other amino acids are replaceable because they are formed in the body through internal processes. Therefore, the usefulness of protein products is largely determined by the content of essential amino acids.
In nutrition of both adults and adolescents involved in physical education and sports, a special role is given to proteins. The lack of proteins in the diet retards growth, reduces resistance to infectious diseases, affects mental development. However, excess protein in the diet is undesirable. It reduces the resistance to stressful situations, causes premature puberty in adolescents.
Rich sources of protein: white meat of chickens and turkeys, liver and meat of calves, fish and fish products, cottage cheese, egg protein.
Fats (or lipids) are also an important energy and building component of food. Fats provide energy to the muscles during prolonged and non-intensive work.
One of the most important functions of fat is the “lubrication” of growing surfaces. With a lack of fat, the joints start to squeak, the hair becomes dry and brittle, a person may experience enhanced catabolism (breakdown of muscle tissue).
In addition, fats provide energy for the breakdown of food proteins and the further construction of the body’s own protein.
Rich sources of unsaturated fat: all types of vegetable oil (sunflower, olive, soybean, canola, corn), nuts (primarily walnuts).
These are “life substances” (“vita” – life), which are present in some foods in small quantities but affect the most important functions of the body (such as hormonal balance, immunity, eyesight and, of course, maintaining muscle tone).
Rich sources of water-soluble vitamins are many fruits, berries, vegetables, and greens, as well as brewer’s yeast and cereal sprouts (for example, oats).
Fat-soluble vitamins in large quantities are found in fish oil, as well as sturgeon roe.
Can a proper diet to provide all the body’s need for vitamins? It’s considered that a balanced daily diet covers the needs of the human body for vitamins and minerals. However, in many cases, one has to use special vitamin supplement preparations that contain either individual missing vitamins or complexes of various vitamins and minerals. It should be noted that the content of vitamins in the diet inevitably decreases in the winter and spring months, when full-fledged sources of vitamins (such as fresh fruits and vegetables) are not always available.
List of essential vitamins that a person needs daily:
- Vitamin A (sweet potatoes, carrots, dairy products, liver, fish oil);
- Vitamin B2 (liver, grains, meat, dairy products);
- Vitamin E (vegetable oils, wheat bran, nuts, green vegetables);
- Vitamin B3 (tuna fish, liver, mushrooms, milk, eggs);
- Vitamin B1 (brewer’s yeast, internal organs of animals, for example, liver, kidneys; legumes, grains);
- Vitamin B6 (poultry, fish, kidney, liver, pork, eggs, unbroken rice);
- Vitamin C (citrus fruits, melons, red and green sweet peppers, broccoli, tomatoes, other vegetables and fruits).
Much of what we talked about vitamins is true for minerals. These are separate low-molecular substances, salts and ions of salts, which support normally many functions of the body even in micro-amounts. Thus, calcium ions provide bone strength, the ratio of potassium and sodium ions determine muscle tone, and the normal level of hemoglobin depends on the iron content in the body, etc. In total, there are more than 30 minerals and trace elements, without which the normal functioning of the body is impossible.
The main sources of minerals are salt, bread, vegetables, fruits, dairy products, cereals, pasta, meat, fish, poultry, seafood, etc.
There are often situations when food cannot provide a balance of minerals. Therefore, people use high-quality multivitamin preparations that contain the necessary supplements of minerals and trace elements.