What are nutrients? Most likely, many people have heard this name more than once in conversations about nutrition, diet and healthy living, but may not have fully understood the transcript.
If we consider the literal translation from English, nutrients are nourishment. A much broader concept explains the following definition: nutrients - micronutrients needed by living organisms to support normal life. In other words, these are the components of food that the body uses for the proper functioning of all cells and tissues. Therefore, people who care about health and follow the diet, take into account not only calories, but also look at the composition of nutrients.
Nutrients are divided into two groups. Micronutrients are substances that the body needs in minimal quantities. They play an important role in the process of assimilation of energy, coordinate various functions related to the growth and development of the body. These include vitamins and a number of minerals. Macronutrients are substances that the body needs in large quantities. These are proteins, fats and carbohydrates - components that are converted into energy or serve as a building material for the body.
Nutrients are non-essential or essential (indispensable). The first category includes substances that can be partially or completely synthesized inside the body by the intestinal microbiome: some vitamins, vitamin-like substances and amino acids. It is important to remember that the human body contains and produces only a certain stock, some of the replacement nutrients must come with food.
Essential nutrients are vital for the body. Deficiency of such substances in the diet can lead to the development of diseases. The list of essential nutrients includes some amino acids, vitamins, fatty acids and minerals.
Let's review the main nutrients in details.
Protein is a key nutrient, the main material that the body uses to build or repair damaged cells and tissues. Proteins affect muscle growth, support the normal functioning of the immune system, regulate biochemical processes required for the production of hormones, enzymes, neurotransmitters, they are carriers of vitamins and other substances. Proteins consist of amino acids linked in a chain. In the digestive tract, these chains are broken down into individual amino acids that enter the bloodstream and then sent to regulate the necessary functions. Proteins are needed by the body in large quantities (60-150 g per day). Many animal proteins are found in foods such as meat, fish, eggs and cheese. From herbal products, choose legumes, cereals, soy, whole grains and vegetables.
The exact amount of protein needed depends on many factors: age, sex, health, lifestyle. For example, during intense sports, during illness, pregnancy and breastfeeding there is an increased consumption of protein, respectively, consumption rates increase. Lack of protein in the diet can lead to:
- increased fragility of hair and nails, because keratin is also a protein that needs to be filled;
- slow wound healing, as the body may not have enough resources to repair damage;
- edema due to water-salt imbalance;
- weight loss, which will be accompanied by weakness and fatigue;
- low body resistance to infectious diseases, because proteins help to form immunoglobulins and antibodies to fight viruses and infections;
- and even a bad mood due to lack of serotonin, in the production of which the protein also plays an important role.
Note that the lack of protein and excess protein is equally harmful to the body. People with kidney disease, high blood pressure and diabetes are recommended to limit their protein intake. Unpleasant complaints of shift in the diet may include thirst, digestive problems, bad breath, hormonal disturbance.
Fats are the main suppliers of energy, they control the degree of saturation, improve taste. Dietary fats are divided into three groups: saturated, polyunsaturated and monounsaturated. The body must receive with food all types of fats. 1 g of fat gives about 9 calories. Knowing your daily energy needs makes it easy to calculate your fat intake. On average, an adult should receive 70-100 g per day, which is 20-30% of total calories. It is important to remember that the essential fatty acids omega-3 alpha-linoleic acid and omega-6 linoleic acid are not synthesized in the body and must be taken with food.
The main functions of fats in the body:
- main source of energy,
- serve as a material for building cell membranes;
- necessary for the synthesis of hormones, including testosterone production;
- coordinate metabolic processes;
- involved in the synthesis of bile acids;
- provide the body with fat-soluble vitamins and promote their rapid assimilation and transportation;
- envelop nerve fibers and affect the proper transmission of nerve impulses;
- maintain the elasticity of blood vessels;
- contribute to the normalization of the skin;
- sources of essential fatty acids.
Sources of saturated fatty acids: butter, lard, hard pressed cheese, as well as visible or hidden fat of meat products (sausages, bacon, sausage), various pastries and fast food. Polyunsaturated fatty acids are found in ocean fish, cod liver, caviar; nuts and seeds, especially in flax seeds and chia; vegetable oils other than palm and coconut; green vegetables and algae. Monounsaturated fatty acids are present in foods such as nuts, seeds, avocado, olive, canola and soybean oils. By following the proper proportion of fat intake, you will provide the body with energy and maintain health.
Carbohydrates are the largest group of nutrients that play a major role in metabolism. There are simple and complex, digestible and undigested. 55-60% of the body's energy comes from the processing of carbohydrates. The human body draws energy from various sources, but brain tissues and nerve cells need a large percentage of energy from carbohydrates.
Simple carbohydrates include fructose and glucose, are easily digested and raise blood sugar. Complex carbohydrates include starch and fiber. They are slowly absorbed or not absorbed at all, give off energy gradually, provide a stable and long-lasting feeling of satiety. According to the recommendations of nutritionists, the share of fast carbohydrates should not exceed 10% of total calories. Therefore, foods such as bread, muffins, cereals should be consumed reasonably. Of all carbohydrates, the share of digestible carbohydrates should be 50%, and the share of undigested carbohydrates - 50%.
The role of dietary fiber should be separated. Despite the fact that herbal fibers are not digested in the body, they are very important for the proper functioning of the gastrointestinal tract. Fiber stimulates the motility of the gastrointestinal tract, maintains normal microflora, promotes the excretion of toxins and wastes, activates digestive enzymes, stabilizes sugar levels.
The benefits or harm depend on the glycemic index, i.e. the rate at which carbohydrates are absorbed and raise blood sugar. Note that the glycemic index is not the rate of increase in glucose, but the amount of carbohydrates in the product, which create a peak concentration of glucose 2 hours after entering the body.
Carbohydrates with a low glycemic index are dissolved slowly, digested longer, do not cause sharp fluctuations in sugar levels and insulin, respectively. They are gradually consumed, retain a feeling of satiety for a long period of time and do not replenish fat reserves. Foods with low glycemic index: kefir, berries and most fruits, vegetables and greens, low-fat yogurt.
Instant cereals, muesli with nuts and raisins, canned fruit, white bread, etc. have a high glycemic index. Such products are needed to replenish strength quickly; people engaged in heavy physical labor, athletes. If the body can not immediately spend all the energy produced, the excess energy deposits in the body. For this reason, there are problems with overweight, metabolic disorders and the risk of developing diabetes.
Water deserves special attention - it's the most important element for life. About 70% of the adult human body consists of water, and almost all processes take place with its participation. The main functions of water:
- to transport nutrients to all cells of the body;
- to help to convert food into energy;
- to promote the absorption of nutrients;
- to play an important role in thermoregulation and maintain normal body temperature;
- to affect blood pressure;
- to remove harmful substances and metabolic products from the body;
- to strengthen the immunity, as it participates in the formation of immune cells and spreads them throughout the body;
- to moisturize oxygen for breathing;
- to suppress hunger and activate metabolic processes;
- to relieve stress, because the brain needs fluid for proper functioning;
- to strengthen muscle tonus and joint mobility;
- to prevent dehydration and preserve youth.
An adult needs 1,5-2 liters of fluid per day, and to be more precise, 30-35 ml of water per kilogram of body weight.
Now let's move on to the substances that the body needs in microscopic doses. Vitamins, antioxidants, minerals and phytonutrients are not included in the structure of tissues, but affect all vital functions.
Vitamins - biologically active ingredients of organic nature, which come from the outside or are synthesized in the body, are part of enzymes, participate in the construction of hormones and regulate biochemical processes. There are fat and water soluble vitamins.
Vitamin A is important for growth, vision, bone and tooth formation, it affects the beauty and youth of skin, hair and nails. Much of it is found in liver, egg yolks, fish oil and dairy products.
B vitamins are involved in metabolism and energy metabolism, affect muscle tonus, support the nervous system and cell growth. Yeast, cereals, cereals and meat contain these vitamins. In case of diseases of the musculoskeletal system and neurological problems, these vitamins are prescribed in addition in the form of supplements.
Vitamin C is necessary for the proper functioning of bone and connective tissue, it is involved in collagen synthesis, cholesterol metabolism, it strengthens the immune system, it's a good antioxidant, maintains the beauty of the body. It is an important vitamin that must be added to the diet. It is contained in large quantities in fresh vegetables and fruits.
Vitamin D is synthesized in the skin under the action of ultraviolet rays and it is obtained from food. It regulates the absorption of calcium and phosphorus, it is responsible for the health of bones and teeth, improves brain function and even prevents dementia. Therefore, a walk outdoors, sunbathe, eat fatty fish, eggs, seafood or take special supplements according to the doctor's advice.
Vitamin E acts as a powerful antioxidant, it fights free radicals, protects cells from damage by active forms pf oxygen. It's important for heart health, muscle development, skin condition and maintaining youth. It is contained in vegetable oil, spinach, almond, broccoli, mango, avocado.
Vitamin K. A small amount is produced in the intestine by the microflora, other needs are met with food. It affects the coagulation system and blood vessel function, participates in bone mineralization and energy processes. They are richest in greens, spinach, broccoli, cabbage, avocado, banana, beef liver and dairy products.
Vitamin P strengthens capillaries, reduces the permeability of the vascular wall. It participates in redox processes and has antioxidant properties. It is contained in many plants, especially rose hips, citrus peels, black currant berries, green tea.
Minerals are no less important for life. Minerals are divided into two groups. Macronutrients: potassium, calcium, magnesium, sodium, fluorine, phosphorus. Micronutrients: iron, copper, zinc, chromium, manganese, molybdenum, iodine, fluorine, selenium, cobalt. Both groups support the proper functioning of all organs and systems. In this case the balance is important, as lack or excess can disrupt the work of the whole body.
Let's focus on some minerals that play a significant role in maintaining good health.
Potassium is a dietary mineral and electrolyte. It is contained in all tissues, it regulates electrical activity, affects muscle contraction, nervous and cardiovascular function .
Magnesium is involved in energy and electrolyte metabolism, regulates cell growth, participates in the synthesis of protein molecules, inhibits excitation in the central nervous system.
Calcium supports bone strength and ability to move, regulates the secretion of hormones and neurotransmitters.
Sodium is an important electrolyte involved in blood circulation and metabolism. It maintains water-salt balance, regulates blood pressure, nervous and muscular systems.
Zinc is important for the growth and development of the body, the formation of the immune system, the activity of the pancreas. Iodine regulates the thyroid gland. Iron is involved in the synthesis of hemoglobin, and its deficiency leads to anemia.
A special group is represented by phytonutrients. These are beneficial substances of herbal origin, bioactive components that have a positive effect on health. For centuries, plants have accumulated reserves to protect against the aggressive effects of the environment. Phytonutrients work as powerful antioxidants, neutralize the action of free radicals. Seasonal vegetables and fruits not only meet the needs of dietary fiber, but also protect against the early signs of aging, support the body and help it fight toxins.
A separate group wants to highlight natural chondroprotectors - substances that regulate metabolic processes in bone and cartilage. The presence of nutrients in the diet such as chondroitin and glucosamine will help to maintain healthy joints and cartilage. Examples of products rich in these components: pig ears, beef tails, red fish. Eat dishes with gelatin on a regular basis: marmalade, jelly, jellied meat and fish.
Virtually all life processes depend on what we eat. Pay attention to the amount of nutrients you eat. Use food to take care of your health.