Food supplies the human body with the energy it needs for full life. And it is thanks to regular nutrition and the complex physicochemical reactions it produces (which is what people call metabolism or metabolism) that life is maintained. Food contains many nutrients, without which any general growth, development and functioning of the body would be impossible. We'll cover these nutrients in lesson two.
Below we will consider:
We will also explain what is the value of each of the substances.
Protein
Proteins are the main building blocks of the body and the basis of its cells and tissues. About 20% of them consists of the human body and more than 50% - cells. The body cannot store proteins in tissues "for later", which is why it is required that they be supplied with food daily.
Proteins contain essential amino acids that are not synthesized in the human body - these are arginine, histidine, threonine, phenylalanine, valine, isoleucine, leucine, methionine, lysine and tryptophan. Proteins can have different biological values, which depend on how much and what amino acids they contain, what is the ratio of essential and non-essential amino acids, and what is their digestibility in the digestive tract.
As a rule, proteins of animal origin have a higher biological value. For example, eggs, liver, meat and milk can boast of the optimal ratio of essential acids. And they are absorbed by 97%, while vegetable proteins are absorbed only by 83-85%, because plant products contain a large amount of non-digestible (ballast) substances.
Plant foods generally contain small amounts of protein and are deficient in methionine, lysine and tryptophan. Only legumes (such as soybeans, beans and peas) are high in protein (24% to 45%). 20% of the protein is found in nuts and sunflower seeds. In terms of amino acid composition, proteins of rye, rice and soy are close to animal proteins.
The body's need for protein is determined by the person's age, sex, nature of work, national dietary habits and climatic conditions in which he lives. Usually, adults who are not engaged in active physical work should take protein per day at the rate of slightly less than 1 g per 1 kg of body weight. Food protein should provide 1/6 of the weight and 10-13% of the total energy requirement of the body, and 55% of the recommended protein intake should be of animal origin. If a child or adult is engaged in physical labor, his need for protein increases.
Fats
Edible fats are esters of higher fatty acids and glycerin. Esters of fatty acids have an even number of carbon atoms, and the fatty acids themselves are divided into two large groups - saturated and unsaturated fats. The former are rich in solid animal fats (there can be up to 50% of the total mass), and the latter are rich in liquid oils and seafood (in many oils, for example, in olive, flaxseed, corn and sunflower oils, unsaturated fats can be up to 90%). In the human body, the normal fat content is 10-20%, however, in cases of fat metabolism disorders, this figure can increase up to 50%.
Fats and fat-like substances make up the cell membranes and membranes of nerve fibers, take part in the synthesis of vitamins, hormones and bile acids. Fat deposits, in turn, are considered the body's energy reserve. The energy value of fats is more than 2 times higher than the value of carbohydrates and proteins. When 1 g of fat is oxidized, 9 kcal of energy is released.
Adults should consume 80 to 100 g of fat per day, which provides up to 35% of the total energy value of the diet. Linoleic and linolenic fatty acids are essential (not synthesized in the body), and must be taken with food. They are found in the fat of a number of fish and marine mammals, nuts and vegetable oils. Together with other higher unsaturated fatty acids, they do not allow the development of atherosclerosis, make the body more resistant to infectious diseases.
As for the nutritional value of fats, it is due to the presence of essential fatty acids, the presence of vitamins A, E and D, their absorption and digestibility. The maximum biological value is inherent in fats with linoleic and other higher unsaturated acids. How well fat is absorbed depends on its melting point: if it is lower than body temperature, then fats are absorbed by 97-98%, and if the melting temperature is 50-60 ° C, then they will be absorbed by only 70-80%.
Along with food, fat-like substances such as fat-soluble vitamins, phospholipids and sterols enter the body. Of the sterols, cholesterol, found in animal products, is the best known. But in the body it can also be synthesized by intermediate metabolic products of fats and carbohydrates.
Cholesterol is a source of hormones and bile acids, plus a precursor to vitamin D3. Once in the blood and bile, cholesterol remains in them as a colloidal solution formed by interaction with phosphatides, unsaturated fatty acids and proteins. When the metabolism of these substances is impaired (or there is a deficiency), cholesterol turns into small crystals that settle on the walls of blood vessels and biliary tract, which is why atherosclerosis develops and gallstones are formed.
Carbohydrates
Foods contain carbohydrates in the form of glucose and fructose (monosaccharides), lactose and sucrose (oligosaccharides), pectin substances, fiber, glycogen and starch (polysaccharides). Carbohydrates are the main source of energy for humans: when only 1 g of carbohydrates are oxidized, 4 kcal are released.
For a person not engaged in physical work, the average need for carbohydrates is 400-500 g per day, 2/3 of the daily ration in weight terms and 60% in caloric terms. If a person is actively working physically, the rate becomes larger.
When choosing food, it is best to stop your choice on polysaccharides, i.e. on products containing pectin, glycogen, starch, etc., and, if possible, avoid oligo-monosaccharides - products containing lactose, fructose, glucose, sucrose, etc. Polysaccharides are digested more slowly, and the dynamics of glucose concentration (the end product of digestion) in body fluids is much more favorable for subsequent metabolism. It is also important that polysaccharides are not sweet in taste, due to which the likelihood of their increased consumption decreases.
The disaccharide lactose can be found in abundance in milk and dairy products. But plants are rightfully considered the main supplier of carbohydrates to the body, because their percentage in them is 80-90% of dry mass. Plant foods also contain a variety of indigestible and indigestible polysaccharides such as cellulose. You need to know that thanks to the coarse fiber, non-digestible food, intestinal motility is stimulated, a number of catabolites (even toxic) in the large intestine are absorbed, cholesterol is excreted, and beneficial intestinal bacteria are supplied with nutrients. On average, an adult should take 25 g of carbohydrates per day.
Vitamins
Vitamins are indispensable nutrients (nutrients) of organic origin and of a wide variety of chemical structures. They are needed for proper metabolism in the human body. Their daily rate is usually measured in mg (milligram) and μg (microgram), and it depends, as before, on the person's age, gender, nature of work and health status.
Vitamins are water-soluble (vitamins of group B and vitamin C) and fat-soluble (vitamins A, D, E, K):
- Almost all B vitamins are found in egg whites, yeast, liver, legumes, and the outer parts of grains.
- Vitamin C (ascorbic acid) is found in green parts of plants, berries, vegetables, citrus fruits and other fruits, in particular in acidic ones, as well as in the kidneys and liver.
- Vitamin A is only rich in animal products - cheeses, sturgeon caviar, cod liver, cattle liver, butter. Plus, it is synthesized in the body through provitamin A (carotene), which is found in orange-colored fruits, berries and vegetables.
- Sources of vitamin D include cod liver oil, fish roe, milk fat, and liver. The synthesis of this vitamin occurs due to the effects of ultraviolet radiation.
- Vitamin E is found in green vegetable leaves, egg yolks and vegetable oils.
- Vitamin K is supplied to the body by the liver, potatoes, tomatoes and leafy vegetables.
Fresh vegetables retain vitamins best of all, so it is recommended to eat them as often as possible. If they are stewed and boiled, the content of vitamins will decrease. And if you make a sourdough or subject vegetables to quick freezing, vitamins will be stored in vegetables for a long time.
The value of vitamins for humans is very great. It is expressed in the fact that vitamins serve as a component that is needed for the proper functioning of enzymes; they take part in metabolic processes, help the body grow and develop, strengthen the immune system. With a lack of vitamins, the mechanisms of the nervous system and the visual apparatus are disrupted, skin problems, vitamin deficiencies and hypovitaminosis appear, the immune status is weakened, etc. It should be remembered that the most deficient (especially during winter and early spring) vitamins are vitamins A, B1, B2 and C.
Minerals
Mineral substances are components of tissues and organs, which explains their huge role in the physical and chemical processes occurring in the body. Some minerals are found in cells, while others are in tissue fluid, lymph and blood (in which minerals are suspended in the form of ions).
Sulfur, chlorine, phosphorus, potassium, magnesium and calcium are considered the most significant for the functioning of the body. These elements help the body build tissues and cells and also support the functions of the central nervous system, muscles, and heart. In addition, they neutralize harmful acids - metabolic products.
Calcium is a building block for bone tissue, and it is especially necessary for children whose skeletons are at the stage of formation. Calcium enters the body with vegetables, fruits and dairy products.
Phosphorus is equally important because also participates in the structure of bones, and more than half of all available phosphorus is in bones. If there is enough phosphorus in the body, there will always be a normal metabolism of carbohydrates and a strong nervous system. Phosphorus is found in legumes, grains, fish, milk and meat.
Naturally, the body needs magnesium, bromine, iodine, zinc, cobalt, fluorine and other trace elements (we will talk in more detail about them, as well as about vitamins in the next lesson), which are contained in food in minimal amounts (less than 1 mg per 1% ). Many enzymes, hormones, vitamins consist of them; they most directly affect the development of the body and metabolism.
A deficiency of any trace element in the body causes specific diseases such as tooth decay (lack of fluoride), severe anemia (lack of copper or cobalt), endemic goiter (lack of iodine) and others. Special attention you need to pay to ensure that the child's body is supplied with minerals. If up to 2 months they are received enough with mother's milk, then at the 3rd month they need to be added to the juices of vegetables, fruits and berries. Starting from the 5th month, it is necessary to supply complementary foods with minerals (oat and buckwheat cereals, meat, eggs, fruits and vegetables).
Water
Water and mineral substances dissolved in it serve as the basis of the internal environment of the body - this is the main part of tissue fluid, lymph and plasma. Not a single vital process in the body (especially thermoregulatory and enzymatic processes) is possible without a sufficient amount of water.
Water exchange is influenced by parameters such as humidity and ambient temperature, dietary patterns, and even behavior and clothing. An adult should provide his body with about 2-3 liters of fluid. Men are advised to drink about 3 liters, and women - about 2.3 liters, and more than half of this amount should be clean drinking water.
Calculation of energy consumption
To maintain each process in the body, a certain amount of energy is spent, provided by food intake. Energy intake and expenditure are expressed in thermal units called calories. A kilocalorie is equal to the amount of heat required to raise the temperature of 1 liter of water by 1 °.
The average indicators of combustion of substances contained in food are as follows:
- 1 g protein \u003d 4.1 kcal
- 1 g fat \u003d 9.3 kcal
- 1 g carbohydrates \u003d 4.1 kcal
Energy for basic energy exchange is the minimum amount of calories needed to meet the body's needs in a state of nervous and muscular rest. If a person works mentally or physically, energy exchange increases, and the amount of nutrients he needs increases.
When the human body is in extreme conditions, for example, if it is starving, the required energy can come from internal structures and reserves (this process is called endogenous nutrition). The human need for energy, based on daily energy consumption, is from 1700 to 5000 kcal (sometimes more). This indicator depends on the sex of the person, his age, lifestyle and characteristics of work.
As we already know, among the nutrients in food, fats, carbohydrates, proteins (proteins), minerals and vitamins are allocated. In terms of calorie content, the daily diet should correspond to daily energy consumption, and metabolism and energy consumption at home and at work should be taken into account. The approximate value of the daily caloric intake, if the minimum daily physical activity is performed, is calculated by multiplying normal mass (in kg) for 30 calories for women and 33 calories for men. Proteins, fats and carbohydrates should be in a ratio of 1: 1: 4. In addition, the quality of the diet also plays a role, which depends on the tastes, habits and the amount of excess body weight of each individual person.
In most cases, nutritionists recommend using diets that are standard in terms of calories (they provide the body with 2200-2700 kcal). But the diet should include different foods - both in calorie content and in quality. You should always remember about the "empty" calories contained in bread, pasta based on white refined flour, white sugar, cookies, cakes and other sweets, sugary soft drinks and alcohol.
Each person should choose for himself such a diet that will provide him with the necessary amount of energy. It is important to ensure that the body receives as few harmful substances and "empty" calories as possible, as well as track your body weight. People who are obese or, conversely, overly thin, should turn to specialists who will help you choose the right diet for every day.
To correctly determine the food, as well as to know how many calories are in a particular product, it is customary to use special tables. Below you will find three such tables - for soft drinks, liquor and the most common foods.
Using the tables is as easy as shelling pears - all drinks and products are grouped and arranged in alphabetical order. Opposite each drink or product there are columns that indicate the content of the required substances and the number of calories (based on 100 g of a specific product). Based on these tables, it is very convenient to create your own diet.
Table 1 (Non-alcoholic drinks)
|
NAME |
PROTEINS |
FATS |
CARBOHYDRATES |
Kcal |
|
Apricot juice |
||||
|
Pineapple juice |
||||
|
Orange juice |
||||
|
Grape juice |
||||
|
Cherry juice |
||||
|
Pomegranate juice |
||||
|
Cocoa in milk |
||||
|
Bread kvass |
||||
|
Coffee with milk |
||||
|
Lemon juice |
||||
|
Carrot juice |
||||
|
Peach juice |
||||
|
Non-alcoholic beer |
||||
|
Green tea |
||||
|
Black tea without sugar |
||||
|
Black tea with lemon and sugar (2 tsp) |
||||
|
Black tea with condensed milk (2 tsp) |
||||
|
Energy drink |
||||
|
Apple juice |
Table 2 (Alcohol)
|
NAME |
PROTEINS |
FATS |
CARBOHYDRATES |
Kcal |
|
Dry wine |
||||
|
Semi-dry wine |
||||
|
Dessert wine |
||||
|
Semi-sweet wine |
||||
|
Table wine |
||||
|
Beer dark |
||||
|
Port wine |
||||
|
Champagne |
Table 3 (Food)
|
NAME |
PROTEINS |
FATS |
CARBOHYDRATES |
Kcal |
|
Apricots |
||||
|
Quince |
||||
|
Cherry plum |
||||
|
A pineapple |
||||
|
Orange |
||||
|
Peanut |
||||
|
Watermelon |
||||
|
Eggplant |
||||
|
Bananas |
||||
|
Mutton |
||||
|
Bagels |
||||
|
Beans |
||||
|
Lingonberry |
||||
|
Brynza |
||||
|
Swede |
||||
|
Gobies |
||||
|
Waffles with fat-containing fillings |
||||
|
Waffles with fruit fillings |
||||
|
Ham |
||||
|
Grapes |
||||
|
Cherry |
||||
|
Cherry |
||||
|
Beef udder |
||||
|
Hercules |
||||
|
Beef |
||||
|
Beef stew |
||||
|
Blueberry |
||||
|
Pink salmon |
||||
|
Shelled peas |
||||
|
Whole peas |
||||
|
Green peas |
||||
|
Garnet |
||||
|
Grapefruit |
||||
|
Walnut |
||||
|
Fresh porcini mushrooms |
||||
|
Dried porcini mushrooms |
||||
|
Fresh boletus mushrooms |
||||
|
Fresh boletus mushrooms |
||||
|
Fresh russula mushrooms |
||||
|
Raw smoked brisket |
||||
|
Pear |
||||
|
Pear |
||||
|
Goose |
||||
|
Dragee fruit |
||||
|
Blackberry |
||||
|
Melted animal fat |
||||
|
Tourist breakfast (beef) |
||||
|
Tourist breakfast (pork) |
||||
|
Green beans (pod) |
||||
|
Marshmallow |
||||
|
Raisins |
||||
|
Chum salmon caviar |
||||
|
Caviar left breakout |
||||
|
Pollock caviar |
||||
|
Granular sturgeon caviar |
||||
|
Sturgeon breakout caviar |
||||
|
Turkey |
||||
|
Fig |
||||
|
Iris |
||||
|
Natural yoghurt (1.5% fat) |
||||
|
Zucchini |
||||
|
Squid |
||||
|
Flounder |
||||
|
White cabbage |
||||
|
Cauliflower |
||||
|
Caramel |
||||
|
Carp |
||||
|
Carp |
||||
|
Potatoes |
||||
|
Chum |
||||
|
Fat kefir |
||||
|
Low-fat kefir |
||||
|
Dogwood |
||||
|
Strawberry wild-strawberry |
||||
|
Cranberry |
||||
|
Cooked sausage Doctor's |
||||
|
Cooked sausage Amateur |
||||
|
Cooked sausage Milk |
||||
|
Cooked sausage Separate |
||||
|
Veal sausage |
||||
|
Cooked-smoked sausage Amateur |
||||
|
Cooked-smoked sausage Cervelat |
||||
|
Semi-smoked sausage Krakowska |
||||
|
Semi-smoked sausage Minsk |
||||
|
Semi-smoked sausage Poltava |
||||
|
Ukrainian semi-smoked sausage |
||||
|
Raw smoked sausage Amateur |
||||
|
Uncooked smoked sausage Moscow |
||||
|
Sausage mince |
||||
|
horsemeat |
||||
|
Chocolate sweets |
||||
|
Raw smoked loin |
||||
|
Smelt |
||||
|
Crab |
||||
|
Shrimp |
||||
|
Rabbit |
||||
|
Buckwheat |
||||
|
Corn groats |
||||
|
Semolina |
||||
|
Oat groats |
||||
|
Pearl barley |
||||
|
Wheat groats |
||||
|
Barley groats |
||||
|
Gooseberry |
||||
|
Dried apricots |
||||
|
Chickens |
||||
|
Icy |
||||
|
Lemon |
||||
|
Green onion (feather) |
||||
|
Leek |
||||
|
Onion |
||||
|
Mayonnaise |
||||
|
Pasta |
||||
|
Macrurus |
||||
|
Raspberries |
||||
|
Mandarin |
||||
|
Margarine sandwich |
||||
|
Milk margarine |
||||
|
Marmalade |
||||
|
Vegetable oil |
||||
|
Butter |
||||
|
Ghee butter |
||||
|
Curd mass |
||||
|
Almond |
||||
|
Lamprey |
||||
|
Pollock |
||||
|
Beef brains |
||||
|
Capelin |
||||
|
Milk |
||||
|
Acidophilic milk |
||||
|
Condensed milk |
||||
|
Condensed milk with sugar |
||||
|
Powdered whole milk |
||||
|
Carrot |
||||
|
Cloudberry |
||||
|
Seaweed |
||||
|
Wheat flour 1 grade |
||||
|
Wheat flour 2 grades |
||||
|
Wheat flour of the highest grade |
||||
|
Rye flour |
||||
|
Navaga |
||||
|
Burbot |
||||
|
Nototenia marble |
||||
|
Sea buckthorn |
||||
|
Cucumbers |
||||
|
Perch |
||||
|
River perch |
||||
|
Olives |
||||
|
Sturgeon |
||||
|
Halibut |
||||
|
Paste |
||||
|
Sweet green pepper |
||||
|
Sweet red pepper |
||||
|
Peaches |
||||
|
Peaches |
||||
|
Parsley (greens) |
||||
|
Parsley (root) |
||||
|
Lamb liver |
||||
|
Beef liver |
||||
|
Pork liver |
||||
|
Cod liver |
||||
|
Sponge cake with fruit filling |
||||
|
Puff pastry with cream |
||||
|
Puff pastry with fruit filling |
||||
|
Tomatoes (tomatoes) |
||||
|
Lamb kidneys |
||||
|
Beef kidney |
||||
|
Pork kidneys |
||||
|
Millet |
||||
|
Curdled milk |
||||
|
Gingerbread |
||||
|
Blue whiting |
||||
|
Whole wheat |
||||
|
Millet |
||||
|
Rhubarb |
||||
|
Radish |
||||
|
Radish |
||||
|
Turnip |
||||
|
Rye |
||||
|
Saber fish |
||||
|
Caspian fish |
||||
|
Rowan red |
||||
|
Rowan chokeberry |
||||
|
Ryazhenka |
||||
|
Carp |
||||
|
Saury |
||||
|
Baltic herring |
||||
|
Salad |
||||
|
Beef sausages |
||||
|
Pork sausages |
||||
|
Sugar |
||||
|
Beet |
||||
|
Fatty pork |
||||
|
Lean pork |
||||
|
Skinny pork |
||||
|
Pork stew |
||||
|
Butter baked goods |
||||
|
Herring |
||||
|
Salmon |
||||
|
Sunflower seed |
||||
|
Lamb heart |
||||
|
Beef heart |
||||
|
Pork heart |
||||
|
Mackerel |
||||
|
Garden plum |
||||
|
Cream 10% fat |
||||
|
Cream 20% fat |
||||
|
Sour cream 10% fat |
||||
|
Sour cream 20% fat |
||||
|
White currant |
||||
|
Red currants |
||||
|
Black currant |
||||
|
Sausages Dairy |
||||
|
Sausages Russian |
||||
|
Pork Sausages |
||||
|
Horse mackerel |
||||
|
Sterlet |
||||
|
Zander |
||||
|
Wheat crackers |
||||
|
Creamy crackers |
||||
|
Protein powder |
||||
|
Dry yolk |
||||
|
Drying |
||||
|
Dutch cheese |
||||
|
Processed cheese |
||||
|
Poshekhonsky cheese |
||||
|
Russian cheese |
||||
|
Swiss cheese |
||||
|
Curd cheeses |
||||
|
Fat cottage cheese |
||||
|
Low-fat cottage cheese |
||||
|
Fat-free cottage cheese |
||||
|
Bold cottage cheese |
||||
|
Fatty veal |
||||
|
Skinny veal |
||||
|
Oatmeal |
||||
|
Sponge cake with fruit filling |
||||
|
Almond cake |
||||
|
Trepang |
||||
|
Cod |
||||
|
Tuna |
||||
|
Coal fish |
||||
|
Acne |
||||
|
Sea eel |
||||
|
Dried apricots |
||||
|
Duck |
||||
|
Beans |
||||
|
Dates |
||||
|
Hazelnut |
||||
|
Sunflower halva |
||||
|
Takhinny halva |
||||
|
Wheat bread from 1 grade flour |
||||
|
Rye bread |
||||
|
Coarse rye bread |
||||
|
Horseradish |
||||
|
Persimmon |
||||
|
Chicks |
||||
|
Ramson |
||||
|
Cherries |
||||
|
Blueberry |
||||
|
Prunes |
||||
|
Garlic |
||||
|
Lentils |
||||
|
Mulberry |
||||
|
Rosehip fresh |
||||
|
Dried rosehip |
||||
|
Milk chocolate |
||||
|
Dark chocolate |
||||
|
Pork fat |
||||
|
Spinach |
||||
|
Sorrel |
||||
|
Pike |
||||
|
Apples |
||||
|
Apples |
||||
|
Beef tongue |
||||
|
Pork tongue |
||||
|
Egg powder |
||||
|
Chicken egg |
||||
|
Quail egg |
In the next lesson, we will dwell in more detail on trace elements and vitamins, find out how much they need a person, and from what products they can be obtained, and also give some very useful tables.
Test your knowledge
If you want to test your knowledge on the topic of this lesson, you can take a short test consisting of several questions. In each question, only 1 option can be correct. After you have selected one of the options, the system automatically proceeds to the next question. The points you receive are influenced by the correctness of your answers and the time spent on passing. Please note that the questions are different each time, and the options are mixed.
First of all, it should be remembered that the basis of proper nutrition is proteins, fats and carbohydrates - a triad of vital nutrients, without which the vital activity of the body is impossible.
Protein
Protein is an irreplaceable part of food. They go to build new cells and replace worn-out ones, actively participate in the metabolism that is continuously occurring in the body. Nutritionists call them "proteins" for a reason - from the Greek word "proteo", which means "taking the first place" or "leading". After all, body proteins are formed only from food proteins.
The main sources of animal protein are meat, fish, cottage cheese, eggs. Plant foods also contain proteins, especially legumes and nuts.
A person gets protein by eating animal and plant foods, but food proteins differ from those that make up human body... During the digestion process, proteins are broken down into amino acids, which are absorbed and used by the body to form its own protein. The most important amino acids are 22. Of these, eight are considered essential. They are called so because the body cannot synthesize them on its own - it receives them only with food, The rest of the amino acids are regarded as nonessential.
Various proteins contain different complexes amino acids, therefore it is very important that the body constantly receives the full set of essential proteins. In nature, there is no such product that in its amino acid composition would coincide with the proteins of the tissues of Homo sapiens. Therefore, the diet must include protein products of both animal and plant origin. In this case, animal proteins should be at least 1/3. The average protein norm in the daily diet of an adult is 100-120 g, with heavy physical work it should be increased to 150-160 g.
Rational nutrition implies a combination of animal and plant products, such a combination ensures the balance of amino acids, promotes better metabolism. Proteins from dairy products are digested most quickly. Fish and meat are well digested (beef is much faster than pork and lamb). This is followed by bread and cereals. Wheat bread proteins made from high-grade flour, as well as semolina dishes are best digested.
Protein foods
Foods with a high protein content (per 100 g of product)
However, one should not forget that an excess of protein in the diet can overload the liver and kidneys with its decay products. Excess proteins lead to increased putrefactive processes in the intestine, as well as the accumulation of nitrogen metabolism products in the acidic side. Restricting protein intake is certainly a must for those suffering from gout, kidney and liver disease.
Fats
Fat is the most powerful source of energy. In addition, fatty deposits ("depot" of fat) protect the body from heat loss and bruises, and the fat capsules of the internal organs serve as support and protection from mechanical damage. Deposited fat is the main source of energy in acute illness when appetite is reduced and absorption of food is limited.
The source of fat is animal fats and vegetable oils, as well as meat, fish, eggs, milk and dairy products. Fats contain saturated and unsaturated fatty acids, fat-soluble vitamins A, B, E, lecithin and a number of other substances necessary for the body. They ensure the absorption of a number of minerals and fat-soluble vitamins from the intestines. Adipose tissue - active reserve of energy material. Fats improve the taste of food and make you feel full. They can be formed from carbohydrates and proteins, but they are not fully replaced by them.
The needs of the body can only be met by combining animal and vegetable fats, since they complement each other with vital substances.
A distinction is made between saturated and unsaturated fatty acids that make up fats. Saturated acids, which include stearic, palmitic, nylon, butyric, are easily synthesized in the body. They have a low biological value and negatively affect fat metabolism, liver function, and contribute to the development of atherosclerosis. Acids of this type are found in large quantities in animals (lamb, beef) and some vegetable (primarily coconut) fats.
Unsaturated fatty acids are biologically active compounds that take an active part in fat and cholesterol metabolism. They also increase elasticity and reduce the permeability of blood vessels, and prevent the formation of blood clots. These acids, especially polyunsaturated (linoleic, linolenic and arachidonic), are not synthesized in the body - they must be supplied there with food. Acids of this type are found in pork fat, sunflower and corn oil, and fish oil.
In addition to fatty acids, fats contain fat-like substances - stearins and phosphatides. They are involved in the secretion of hormones, the process of blood coagulation, and the formation of cell membranes. The most famous of the stearins is cholesterol, which is found in large quantities in animal products. Excess cholesterol in the body leads to undesirable changes in the blood vessels, contributes to the development of atherosclerosis. Therefore, it is recommended to limit the diet of foods rich in cholesterol (egg yolk, brains, butter, fatty meats, cheese and dairy products with a high fat content), and eat more foods containing lecithin and choline (vegetables, fruits, skim milk and sour cream) ...
The daily rate of fat for an adult is from 100 to 150 g with hard physical work, especially in the cold. On average, the daily diet of fat should consist of 60-70% of animal fat and 30-40% of vegetable fat.
Foods with a high fat content (per 100 g of product)
| Product | The amount of fat, g |
| Butter (vegetable, ghee, butter), margarines, cooking fats, pork fat | more than 80 |
| Sour cream of 20% (and higher) fat content, cheese, pork, duck, geese, semi-smoked and boiled sausages, cakes, halva and chocolate | from 20 to 40 |
| Fat cottage cheese, creamy ice cream, cream, lamb, beef and chickens of the 1st category, eggs, beef sausages, tea sausage, salmon, sturgeon, saury, fat herring, caviar | from 10 to 19 |
| Milk, fat kefir, semi-fat cottage cheese, milk ice cream, lamb, beef and chickens of the 2nd category, pink salmon, mackerel, horse mackerel, pastry, candies | from 3 to 9 |
| Fat-free cottage cheese and kefir, pike perch, cod, pike, hake, cereals, bread | less than 2 |
When using fats, do not forget that their excess impairs the absorption of proteins, calcium and magnesium. To ensure proper fat metabolism, it is necessary to take enough vitamins. Abundant consumption of foods high in fat inhibits the secretion of gastric juice, delays the excretion of food from the stomach, and overstrains the functions of other organs involved in the breakdown and absorption of food. Excess fat leads to digestive disorders. They pose a serious danger in chronic diseases of the liver, pancreas, gastrointestinal tract and biliary tract.
Carbohydrates
Carbohydrates serve as the body's main source of energy and help our muscles work. They are essential for the normal metabolism of proteins and fats. In combination with proteins, they form certain hormones, enzymes, secretions of salivary and other mucus-forming glands, and other important compounds. The average rate of carbohydrates in the daily diet should be 400-500 g.
Carbohydrates are classified into simple and complex carbohydrates. Simple carbohydrates differ from complex ones in chemical structure. Among them, there are monosaccharides (glucose, galactose, fructose) and disaccharides (sucrose, lactose and maltose). Simple carbohydrates are found in sugary foods like sugar, honey, maple syrup, etc.
Complex carbohydrates are called polysaccharides, their source is plants - cereals, vegetables, legumes. Complex carbohydrates include starch, glycogen, fiber, pectins, hemicellulose, etc. Polysaccharides form the basis of dietary fiber, so they play an important role in nutrition.
The main suppliers of sucrose for the body are sugar, confectionery, jam, ice cream, sweet drinks, as well as some vegetables and fruits: beets, carrots, apricots, peaches, sweet plums, etc. In the intestine, sucrose is broken down into glucose and fructose. In the 70s. XX century sugar was branded as the "white death". “It is worse than opium and more dangerous than a nuclear bombardment,” wrote W. Daphnia in her book “Sweet Blues”, after which the sugar persecution began. Today the harmfulness of sugar is being questioned. In a 2002 WHO expert report, it is said that dietary sugars are attributed only to factors that increase the risk of dental caries, but not cardiovascular, oncological and other mass diseases. And although sugar itself is not dangerous for humans, its excess (instead of other products) consumption reduces the nutritional value of any diet.
Glucose (dextrose) - the main supplier of energy for the brain, red blood cells and muscle cells - is found in fruits and berries. In a person weighing 70 kg, the brain consumes about 100 g of glucose, striated muscles - 35 g, erythrocytes - 30 g. Glucose is necessary for the formation of glycogen in the liver. In addition, it is involved in the regulation of appetite. A drop in blood glucose signals the need to eat something.
Glycogen - animal carbohydrate, polysaccharide, glucose polymer, similar to starch. The body contains about 500 g of glycogen. Food sources of glycogen are liver, meat of animals and birds, fish.
Fructose (levulose) has the greatest sweetness of all natural sugars. It almost does not require the hormone insulin for its assimilation, so it can be used for diabetes mellitus, albeit in limited quantities.
Lactose (milk sugar) is found in dairy products. This carbohydrate normalizes the activity of beneficial microflora, suppresses the processes of putrefaction in the intestines, and promotes the absorption of calcium. With a congenital or acquired deficiency of the enzyme lactose in the intestine, its breakdown into glucose and galactose is disturbed. This leads to intolerance to dairy products. Fermented milk products contain less lactose than whole fresh milk. when fermented from lactose, lactic acid is formed.
Maltose (malt sugar) - an intermediate product of the breakdown of starch by digestive enzymes and enzymes of germinated grain (malt). The resulting maltose breaks down to glucose. Free maltose is found in honey, malt extract, and beer. Starch makes up about 85% of all carbohydrates in the human diet. Its sources are flour, bread, legumes, cereals, pasta, and potatoes. Starch is relatively slowly digested, breaking down into glucose. At the same time, starch from rice and semolina is digested more easily and faster than from millet, buckwheat, pearl barley and barley groats, from potatoes and bread. Starch is very quickly absorbed in jelly, i.e. in kind.
Alimentary fiber - a complex of carbohydrates (fiber, hemicellulose, pectins, gums, mucus) and lignin, which is not a carbohydrate. Dietary fiber is abundant in bran, wholemeal flour and bread made from it, cereals with shells, nuts and legumes.
Cellulose - complex carbohydrate. The human body does not digest fiber, however, it enhances intestinal motility and therefore is necessary for proper digestion. With the help of fiber, cholesterol is removed from the body. Insoluble fiber also removes waste products, preventing contamination of the body with harmful substances. Fiber is present in many vegetables, fruits, and wheat bran.
Pectins stimulate digestion and also contribute to the elimination of harmful substances from the body. Many pectins are found in apples, plums, peaches, apricots, gooseberries, cranberries, as well as in some vegetables - cabbage, potatoes, cucumbers, eggplants and onions. Pectins are useful because they reduce putrefactive processes in the intestines and promote healing of the intestinal mucosa.
Inulin - polysaccharide, polymer of fructose. A large amount of inulin is found in Jerusalem artichoke, artichokes and chicory.
Hemicellulose - a polysaccharide of the cell wall capable of retaining water. Most of all hemicellulose is present in cereal products.
Foods containing carbohydrates
Foods with a high carbohydrate content (per 100 g of product)
When calculating the amount of carbohydrates in the diet, you should avoid excessive consumption of them, which can lead to obesity. Everyday and excessive consumption of sugar (foods high in sugar) contributes to the manifestation of latent diabetes mellitus.
It should be remembered that sugar itself is not the cause. Sweet foods are a kind of catalysts (accelerators) of an already arisen disease, since they overload the pancreas and significantly deplete the cells that produce insulin, which is necessary for glucose uptake.
However, limiting the amount of carbohydrates to a minimum is also not recommended. Even with a diet in the daily diet, they should be at least 100 g. With a lack of carbohydrates in the body, the metabolism of fats and proteins is disturbed. They accumulate in the blood harmful products incomplete oxidation of fatty acids and some amino acids. Against this background, the symptoms of carbohydrate deficiency develop: drowsiness, hunger, headaches, weakness, dizziness, nausea, sweating, trembling hands. To regain good health, you should drink a cup of sweet tea or suck on a sugar cube as soon as possible.
The basics of good nutrition
The aim of a rational, balanced diet is to provide adequate nutrition in accordance with the physiological needs of the body.
The most optimal ratio for proteins, fats and carbohydrates is 1: 1: 4 (5). This means that the daily diet of a healthy working person should contain approximately 100 g of protein (including 65 of animal origin), 80-100 g of fat (including at least 30 g of vegetable origin) and 400-500 g of carbohydrates.
Any diet, in addition to proteins, fats and carbohydrates, should provide for the consumption of mineral elements (within the physiological norm) and vitamins (moreover, ascorbic acid and B vitamins - in an amount doubled against the norm: 100 mg of vitamin C and 4-5 mg of vitamins B , and B2).
For this purpose, the menu includes salads and side dishes from fresh vegetables, fruits and berries, freshly squeezed juices, rosehip decoctions, bran, yeast drink. Table salt is allowed in normal quantities (10 g per day). The intake of liquid, depending on the season, can reach 1.5 - 2 liters.
When these conditions are met, food intake corresponds to energy expenditure, body weight does not change, and a person feels great.
Nutrients - carbohydrates, proteins, vitamins, fats, microelements, macronutrients - are found in food. All these nutrients are necessary for a person to be able to carry out all life processes. The nutrient content of the diet is the most important factor in making diet menus.
In the body of a living person, the oxidation processes of all kinds of nutrients... Oxidation reactions occur with the formation and release of heat, which a person needs to maintain vital processes. Heat energy allows you to work muscular system, which leads us to the conclusion that the harder the physical labor, the more food is required for the body.
The energy value of foods is determined by calories. The calorie content of foods determines the amount of energy received by the body in the process of assimilating food.
1 gram of protein in the oxidation process gives 4 kcal of heat; 1 gram of carbohydrates \u003d 4 kcal; 1 gram of fat \u003d 9 kcal
The nutrients are proteins.
Protein as a nutrient is necessary for the body to maintain metabolism, muscle contraction, irritability of nerves, the ability to grow, reproduce, and think. Protein is found in all tissues and body fluids and is an essential element. Protein consists of amino acids that determine the biological significance of a particular protein.
Essential amino acids are formed in the human body. Essential amino acids a person receives from the outside with food, which indicates the need to control the amount of amino acids in food. Lack of even one essential amino acid in food leads to a decrease in the biological value of proteins and can cause protein deficiency, despite a sufficient amount of protein in the diet. The main source of essential amino acids is fish, meat, milk, cottage cheese, eggs.
In addition, the body needs vegetable proteins contained in bread, cereals, vegetables - they provide essential amino acids.
An adult's body should receive approximately 1 g of protein per 1 kilogram of body weight every day. That is, an ordinary person weighing 70 kg per day needs at least 70 g of protein, while 55% of all protein should be of animal origin. If you are doing physical exercise, then the amount of protein should be increased to 2 grams per kilogram per day.
Proteins in a proper diet are irreplaceable by no other elements.
The nutrients are fats.
Fats as nutrients are one of the main sources of energy for the body, participate in recovery processes, as they are a structural part of cells and their membrane systems, dissolve and help in the assimilation of vitamins A, E, D. In addition, fats help in the formation of immunity and preservation of heat in the body ...
An insufficient amount of fat in the body causes disturbances in the activity of the central nervous system, changes in the skin, kidneys, and vision.
Fat consists of polyunsaturated fatty acids, lecithin, vitamins A, E. An ordinary person needs 80-100 grams of fat a day, of which at least 25-30 grams of plant origin should be.
Fat from food gives the body 1/3 of the daily energy value of the diet; there are 37 g of fat per 1000 kcal.
The required amount of fat in: heart, poultry, fish, eggs, liver, butter, cheese, meat, lard, brains, milk. Vegetable fats, which have less cholesterol, are more important for the body.
The nutrients are carbohydrates.
Carbohydrates, nutrient, are the main source of energy, which brings 50-70% of calories from the entire diet. The required amount of carbohydrates for a person is determined based on his activity and energy consumption.
An ordinary person who is engaged in mental or light physical labor needs about 300-500 grams of carbohydrates per day. With magnification physical activity increases and daily rate carbohydrates and calories. For overweight people, the energy intensity of the daily menu can be reduced by the amount of carbohydrates without harm to health.
A lot of carbohydrates are found in bread, cereals, pasta, potatoes, sugar (pure carbohydrate). An excess of carbohydrates in the body disrupts the correct ratio of the main parts of food, thereby disrupting metabolism.
The nutrients are vitamins.
Vitamins, as nutrients, do not give energy to the body, but are still essential nutrients necessary for the body. Vitamins are needed to maintain the body's vital functions, regulating, directing and accelerating metabolic processes. The body receives almost all vitamins from food and only some of the body can produce itself.
In winter and spring, hypoavitaminosis may occur in the body due to a lack of vitamins in food - fatigue, weakness, apathy increase, efficiency and resistance of the body decrease.
All vitamins, according to their effect on the body, are interconnected - a lack of 1 of the vitamins gives a metabolic disorder of other substances.
All vitamins are divided into 2 groups: water-soluble vitamins and fat-soluble vitamins.
Fat-soluble vitamins - vitamins A, D, E, K.
Vitamin A - is needed for the growth of the body, improving its resistance to infections, maintaining good vision, the condition of the skin and mucous membranes. Vitamin A comes from fish oil, cream, butter, egg yolk, liver, carrots, lettuce, spinach, tomatoes, green peas, apricots, oranges.
Vitamin D - is needed for the formation of bone tissue, the growth of the body. A lack of vitamin D leads to a deterioration in the absorption of Ca and P, which leads to rickets. Vitamin D can be obtained from fish oil, egg yolk, liver, and fish roe. Vitamin D is still present in milk and butter, but just a little.
Vitamin K - needed for tissue respiration, normal blood clotting. Vitamin K is synthesized in the body by intestinal bacteria. Lack of vitamin K appears due to diseases of the digestive system or the intake of antibacterial drugs. Vitamin K can be obtained from tomatoes, green parts of plants, spinach, cabbage, nettle.
Vitamin E (tocopherol) is needed for the activity of the endocrine glands, the exchange of proteins, carbohydrates, and the provision of intracellular metabolism. Vitamin E has a beneficial effect on pregnancy and fetal development. Vitamin E is obtained from corn, carrots, cabbage, green peas, eggs, meat, fish, olive oil.
Water-soluble vitamins - vitamin C, B vitamins.
Vitamin C (ascorbic acid) - is needed for the body's oxidation-reduction processes, carbohydrate and protein metabolism, increasing the body's resistance to infections. Rich in vitamin C fruits of rose hips, black currants, chokeberries, sea buckthorn, gooseberries, citrus fruits, cabbage, potatoes, deciduous vegetables.
Vitamin B group includes 15 water-soluble vitamins that take part in metabolic processes in the body, the process of hematopoiesis, play an important role in carbohydrate, fat, water metabolism. B vitamins stimulate growth. You can get B vitamins from brewer's yeast, buckwheat, oatmeal, rye bread, milk, meat, liver, egg yolk, green parts of plants.
Nutrients - micronutrients and macronutrients.
Nutrient minerals are part of the cells and tissues of the body, participate in various metabolic processes. Macronutrients are necessary for humans in relatively large quantities: Ca, K, Mg, P, Cl, Na salts. Trace elements are required in small quantities: Fe, Zn, manganese, Cr, I, F.
Iodine can be obtained from seafood; zinc from cereals, yeast, legumes, liver; copper and cobalt are obtained from beef liver, kidneys, chicken egg yolk, honey. Berries and fruits contain a lot of potassium, iron, copper, phosphorus.
Good nutrition is the holistic science of food and its effects on health. The nutrients that the body itself cannot synthesize must come from food. Some of the nutrients required for normal functioning include:
- minerals;
- fatty acid.
The body needs some of these substances (microelements) in very small quantities, while others, on the contrary, a little more (macronutrients). Lack of any of the nutrients often leads to the development of serious diseases. Excess often leads to obesity and side problems.
Macronutrients Basics
Macronutrients, or macronutrients, are nutrients that provide the body with the energy and calories it needs. They are essential for normal growth, metabolism and maintenance of bodily functions.
Already based on the name, it becomes clear: macronutrients are a group of substances that are necessary for humans in large quantities. Macronutrients include: proteins, fats, carbohydrates.
Many are puzzled by the question of what the percentage of these substances should be in the daily diet and how many grams of each element should be received daily. But in order to answer it, it is important to understand what these elements are and what functions they perform.
These three classes of macronutrients are complex groups, each of which consists of many components. You can eat the same amount (in grams) of proteins, lipids and carbohydrates every day, but at the same time provide the body with different trace elements each time - the whole reason is in the sources of these substances. For example, in identical servings of olive oil and lard, lipids are dramatically different. Therefore, it is important to follow a balanced diet and a varied diet to maintain harmony in the body. And immediately the first conclusion: it is not so much the amount of consumption of useful micro- and macroelements (although this is also an important nuance) that matters, but their quality.
But when it comes to supplying calories, it is still worth remembering that the energy value in 1 gram:
- carbohydrates - 4 calories;
- proteins - 4 calories;
- fat - 9 calories.
Is a combination of different molecules that provide approximately 45 percent of the body's energy. True, some types of carbohydrates, such as resistant starches, do not serve as a source of energy, but they play an equally important role:
- strengthen the health of the digestive system;
- promote easy digestion of food and the absorption of nutrients;
- get rid of toxins and toxins.
Functions in the body
Carbohydrates obtained from food are broken down in the human body to the state of glucose and other monosaccharides. They increase plasma sugar levels, supply a person with energy. In general, the role of most carbohydrates for humans boils down to the fact that they:
- are a great source of strength;
- all cells and tissues of the body use them for energy;
- accumulate in liver cells and in muscle tissue, in order to activate if necessary;
- necessary for the functioning of the nervous system, brain, muscles (in particular, the heart), kidneys;
- have a beneficial effect on maintaining intestinal health.
Carbohydrates are made up of carbon, hydrogen and oxygen. Distinguish between simple and complex carbohydrates.
Monosaccharides and disaccharides
Simple carbohydrates are composed of monosaccharides and disaccharides. They are able to increase glucose levels quickly enough. Sweet to the taste, digestible quickly and instantly provides the body with energy.
Monosaccharides are simple sugars because they are made up of one block. In this form, they can be absorbed by the body. Unlike other carbohydrates, they do not need to be broken down during digestion. Therefore, monosaccharides from food quickly enter the bloodstream, almost instantly increasing the amount of sugar in the plasma, and immediately supply energy to the body.
Examples of monosaccharides: glucose, fructose, galactose. Simple sugars are found in different quantities in foods from different categories. Their content is especially high in ripe fruits and honey.
Monosaccharides are important sources of energy. But consuming large amounts of simple sugars, without balancing with polysaccharides or oligosaccharides (which take longer to digest and therefore provide the body with long-term energy), can cause a significant rise in blood glucose, followed by a sharp drop in blood glucose. As a result, at first there is a large and sharp release of energy, which just as quickly gives way to a feeling of tiredness. Frequent repetition of these fluctuations can lead to diabetes.
Disaccharides
Disaccharides are combinations of 2 monosaccharides. Disaccharides include:
- (milk sugar);
- sucrose (table);
- maltose;
- isomaltose (sugar formed by the breakdown of starch).
Disaccharides, like monosaccharides, give food a sweet taste and provide the body with quick energy. Due to these biochemical properties, they are also referred to as simple sugars. They are abundant in processed foods. Frequent consumption of disaccharides can also lead to high blood glucose levels.
Since disaccharides contain 2 “pieces” of sugar, they undergo a “separation” process before being absorbed into the body. Therefore, for each disaccharide, the body has "prepared" its own digestive enzyme. So, the enzyme sucrase acts on sucrose, lactase - on lactose. Essential enzymes are produced in the intestines. The assimilation of disaccharides is fairly easy. The exception is lactose.
Many people lack the enzyme lactase, which means that their bodies are not able to break down lactose into 2 elements, which manifests itself in the so-called lactose intolerance. This means that the consumption of dairy products is a problem for such people. Lactose intolerance is more common in old age. Undigested milk sugar is not digested and promotes the development of "bad" (unfavorable for the body) bacteria in the digestive tract. As a result, this process leads to flatulence, heartburn and nausea. In addition, the acid produced by "bad" bacteria impairs the functioning of the intestine as a whole (reduces its ability to produce enzymes for digesting food), damages the cells of the digestive system. It is important for such people to give up food that contains lactose. Some studies show that supplements containing lactobacillus are beneficial for these digestive disorders.
Large carbohydrate molecules (such as fiber or starch) are a combination of several monosaccharides bound together. Some may contain up to several hundred mono-sugars. Such a complex is called polysaccharides (from "poly" - a lot). The specificity of complex compounds is that they increase the glucose level in the human body more slowly, but act for a longer time. The group of complex carbohydrates is represented by starches and fiber.
Plants store their energy by combining many mono-sugars. Such a complex can consist of several hundred (sometimes up to several thousand) glucose molecules. Plant foods (such as seeds, which are supposed to provide strength to the shoots) contain a lot of starch. When a young plant begins to grow, the starch is broken down into glucose and supplies it with the necessary energy.
Starch
If a person eats starchy foods such as potatoes, the body uses the polysaccharides from them in much the same way as plants. Digestion of starches takes longer than the processing of disaccharides.
According to the poem, starch is a sustainable source of energy. They do not cause a sharp saturation of blood sugar, the work of starch is designed for slow, consistent and long-term maintenance of strength in the body. And it is considered ideal for health.
There are 2 main types of starches in food:
- amylose;
- amylopectin.
Amylopectin is digested faster by the body. The process of absorption of food starches is preceded by the stage of splitting the substance into smaller elements - individual units of carbohydrates.
Cellulose (fiber)
Food cellulose, or fiber, is also a member of the polysaccharide family of complex carbohydrates. But in this substance the "sugar" blocks are connected according to a slightly different principle and the body cannot break the chains connecting them. Instead, cellulose passes through the small and large intestines as they are. Thanks to this, fiber performs important functions for the body:
- accelerates the elimination of toxins and toxins;
- relieves constipation.
Useful cellulose is found in vegetables, grains, and legumes. In particular, unprocessed food contains more fiber. For example, bran contains a lot of fiber, but flour does not already have it. Cellulose is also present in fruit skins, but is completely absent from fruit drinks.
Much has been written about the benefits of fiber. Experiments show a link between a high-fiber diet and a reduced risk of developing cancer, including in the intestines and mammary glands. Some researchers attribute this to the ability of cellulose to remove waste and toxins from the body, which promotes healthy digestion.
Therefore, foods high in fiber should be included in weight loss diets. In addition, fiber maintains the state of the intestinal microflora, on which the immunity of the whole organism depends. A cellulose deficiency in the diet causes constipation and increases the likelihood of hemorrhoids or colon cancer.
The beneficial effects of fiber:
- reduces the possibility of developing cardiovascular diseases;
- prevents the development of obesity;
- lowers cholesterol.
Resistant starch
The last category of polysaccharides, or complex carbohydrates, is resistant (resistant). It got its name due to the fact that it cannot be processed in the small intestine. As a result, this type of starch acts more like cellulose than starch. Passing through the digestive tract and entering the colon, like fiber, it promotes the production of beneficial bacteria in the intestines. Resistant starch is found in wild rice, barley, whole wheat, and buckwheat.
In addition, there are so-called oligosaccharides in the "sugar family". This is a cross between mono- and polysaccharides. Their structure can contain from 1 to 10 monosaccharides.
Energy sources
Sources of Simple Carbohydrates:
- fruits and berries;
- vegetables;
- milk products;
- sweeteners (sugar, honey, syrup);
- candies;
- soft drinks.
Complex Carbohydrate Source:
- bakery products;
- cereals;
- pasta;
- beans;
- peas;
- starchy vegetables;
- green pea;
- corn.
Many of these foods are also sources of fiber. Complex carbohydrates are found in most vegetables, fruits, nuts, seeds, legumes, and whole grains.
What is the glycemic index
How quickly sugars raise blood glucose is indicated by the glycemic index. Its range is on a scale from 1 (slowest effect on the body) to 100 (fastest satiation, this indicator is equivalent to the rate of action of pure glucose).
| Category | Product | GI |
|---|---|---|
| Legumes | Lentils red | 33 |
| Soy | 14 | |
| Bread | Coarse rye flour | 49 |
| White | 69 | |
| Wholegrain | 72 | |
| Flakes | All the bran | 54 |
| Corn | 83 | |
| Oat | 53 | |
| Rice | 90 | |
| Wheat | 70 | |
| Dairy products | Milk, yogurt, ice cream | 34-38 |
| Fruit | An Apple | 38 |
| Banana | 61 | |
| Orange | 49 | |
| Strawberry | 32 | |
| Cereals | Barley | 22 |
| Brown rice | 66 | |
| White rice | 72 | |
| Pasta | 38 | |
| Potatoes | 86 | |
| Corn chips | 72 | |
| Oat cookies | 57 | |
| Potato chips | 56 | |
| Sugar | Fructose | 22 |
| Glucose | 100 | |
| Honey | 91 | |
| Refined sugar | 64 |
Carbohydrates with a high glycemic index rise quickly in the circulatory system. As a result, the amount of insulin in the blood increases, causing hypoglycemia and hunger. All this leads to the use of extra calories, which means excess weight.
Carbohydrates with a low glycemic index promote a slow rise in plasma glucose, which eliminates sudden surges in insulin production. Eating foods with a lower GI reduces the risk of developing obesity, diabetes, or its complications.
are an important component of the body, as they are part of the structure of most tissues, including bone and connective tissue. The importance of proteins is indicated by their name: "protein" from Greek means "in first place." Proteins are involved in almost all enzymatic processes in the body. Moreover, enzymes are also proteins. The body needs a constant replenishment of proteins, which take the place of dead cells or damaged tissues. Also, the growth and development of the body depends on them. 10 to 35 percent of the calories in your daily diet should come from protein foods.
The role of proteins:
- contribute to the normal growth of children and adolescents;
- necessary to maintain the health of pregnant women;
- restore tissues;
- strengthen the immune system;
- provide the body with energy when there is not enough carbohydrates;
- support muscle mass (promote muscle growth);
- promote the production of hormones and enzymes.
How does the body benefit from proteins?
Proteins are broken down into peptides and amino acids. They are necessary for the growth and replacement of “damaged” tissue sites. But if the body does not receive the necessary calories for life, protein can also be used as a source of energy.
Of the 20 amino acids, 9 are essential. A person cannot synthesize them, therefore it is important to ensure the replenishment of these substances from food.
Protein intake
The daily protein intake is determined based on several parameters. One of them is the growth rate. That is, children in the period of active development need more protein than adults.
Protein intake rates (per day):
- children under 3 years old - 2.2 g per kilogram of weight;
- from 3 to 5 years - 1.2 g per kilogram of weight;
- adults - 0.8 g per kilogram of weight.
People looking to increase muscle mass also need an increased dose of protein.
Protein Sources:
- seafood;
- lean meat;
- bird;
- eggs;
- beans;
- peas;
- soy products;
- seeds;
- dairy products.
Proteins from plant foods are generally lower in fat and cholesterol, and provide the body with fiber and other essential nutrients.
Protein replenishment in the body is achieved by supplying essential amino acids.
Proteins are made up of smaller molecules (amino acids) linked together. The structure of the protein resembles beads strung on a chain. The activated protein takes on a slightly different shape - a three-dimensional structure (the chain is twisted and twisted around). Like carbohydrates, amino acids are made up of carbon, hydrogen, and oxygen. But unlike them, they also contain nitrogen.
It is important that proteins come in different sizes. Some amino acid chains are quite short and consist of 50 elements, but most contain 200-400. Individual proteins can combine and form so-called protein complexes. The largest protein complexes are bones, skin, nails, hair, teeth. They are formed from collagen, elastin and keratin. Collagen, for example, is composed of 3,000 amino acids twisted into a long, cylindrical chain. This chain attaches to other collagen chains and creates thicker and stronger cylinders called fibrils. Fibrils can combine from 6 to 20 collagen chains, which means that they contain tens of thousands of amino acids. And this is the structure of only one protein taken separately.
A single amino acid resembles a simple carbohydrate. At least because the body, according to the principle of digestion of carbohydrates, also breaks the protein structure to the state of an amino acid before absorption. And only after that it digests one small "block".
Where to look for amino acids?
A healthy person needs about 40-65 grams of different amino acids per day. If the body does not receive the required amount of protein, it begins to draw reserves from its own muscles, destroying them. An inadequate intake of amino acids can lead to stunted growth, poor muscle development, thin and brittle hair, skin diseases, a weakened immune system and other troubles.
The source of amino acids are proteins from food of plant and animal origin. Foods most concentrated in protein: nuts, legumes, fish, meat and dairy products. In processed food, protein is sometimes presented in the form of a peptide - a hydrolyzed protein (consists of amino chains formed from 2-200 amino acids). These foods are faster to digest and easier to digest.
Essential amino acids
There are 20 types of amino acids and all of them are needed by the body, since each is involved in the creation of protein at a certain level. The body is able to synthesize many of these amino acids on its own. However, 9 of them are sourced only from food. They are called essential, or essential, amino acids. These include leucine, methionine, tryptophan and others.
The correct ratio of amino acids to each other is important for the body. Animal food, for example, contains amino acids in the same proportion as in the human body. Proteins from plant foods have a slightly different structure. Many dietitians are concerned that vegetarians are not getting all the protein they need when they cut meat. Other researchers reject this theory. They suggested that since different plant foods contain different essential amino acids, it is easy to get all the vital building blocks by eating a variety of foods (from whole grains, legumes, other vegetables). In addition, some plant foods, such as soy, contain protein that is similar in composition to meat proteins.
, or lipids, are perhaps the most complex macromolecules in food. There are many types of lipids.
Unfortunately, fats have gotten a bad reputation, in part because excess calories are converted into subcutaneous fat. The second reason is that saturated lipids, trans fats, cholesterol are the cause of many health problems (from cardiovascular disease to obesity). However, the facts prove that not all fats are bad. Most of them, on the contrary, are vital for the body. So, when it comes to fats, you need to be able to distinguish between good and bad, to understand what type of lipids can be obtained from a particular food.
According to the advice of nutritionists, calories daily diet should be 25-35 percent healthy fats.
Role in the body:
- promote normal growth and development;
- serve as a source of energy;
- necessary for the absorption of fat-soluble vitamins;
- are part of the building material for cells;
- create "amortization" for the internal organs.
Fats, like other macromolecules, are composed of carbon, hydrogen and oxygen. But the peculiarity of their structure is that they are insoluble in water. These are the so-called hydrophobic substances. Fats are broken down into fatty acids and glycerin. They are essential for tissue growth and hormone production.
By their chemical properties, fats are saturated, monounsaturated and polyunsaturated.
Saturated lipids: "bad" fats, who are you?
Saturated lipids are made up of the right molecules. They remain solid at room temperature (excluding palm and coconut oils). Sources of these fats: oil and fats found in meat.
More than 50 years ago, researchers started talking about the relationship between saturated fat and the rate of increase in blood cholesterol, which is the cause of atherosclerosis and cardiovascular diseases. The food industry quickly reacted to the scientists' statement - “low-fat” or “completely fat-free” products appeared on supermarket shelves.
Consuming too much saturated fat can actually have a negative impact on health. But the problem is that the fact about saturated fat exclusively has mistakenly extended to other types of lipids that the body needs.
They are found in large quantities in meat products, in particular in pieces with white solid fat. Minimizing your intake of saturated fat is a good idea. However, you cannot give up all fats. It is also important to consider the fact that the brain is almost 60 percent lipids. In addition, a diet low in all types of fats increases the risk of hormonal disorders, promotes the development of cardiovascular disease, and also reduces immunity and brain activity.
The Importance of Monounsaturated Fats
Monounsaturated fats attracted the attention of scientists after it was noticed that people who follow a Mediterranean diet are less likely to develop heart disease, certain types of cancer, rheumatoid arthritis. Scientists attributed this fact to the fact that the traditional Mediterranean diet contains large amounts of olive oil, which is rich in monounsaturated oleic fatty acid. In addition to the olives product, avocados, almonds and cashews are rich in monounsaturated lipids.
Monounsaturated fats (such as olive oil) retain their liquid structure at room temperature, but solidify in the refrigerator.
Scientists continue to conduct experiments and prove their theory about useful properties monounsaturated fat. But the functions of polyunsaturated lipids, in particular the omega-3 fatty acid, are being studied no less actively.
Polyunsaturated substances
Polyunsaturated fats (PUFAs) are composed of molecules, the nature of the bonds between which differs from other lipids. This is the secret of why they remain liquid at low temperatures.
There are many polyunsaturated fats. Most of them can be produced by humans on their own, except for Omega-6 and Omega-3. And since these fatty acids are essential for humans, it is important to replenish them from food.
Polyunsaturated lipids are present in large quantities in oils from grains and seeds (for example, flaxseed oil).
When it comes to lipids, one cannot help but remember the essential fatty acids - linoleic (Omega-6) and linolenic (Omega-3). They are necessary for the formation of biologically active lipids (eicosanoids), including prostaglandins, thromboxanes, prostacyclins and leukotrienes. Regular consumption of omega-3 fatty acids prevents the development of coronary heart disease.
The body's need for essential fatty acids varies with age.
For adults:
- linoleic acid - 2% of daily calories;
- linolenic acid - 0.5% of the total calories.
Linoleic acid, also known as Omega-6, is found in large quantities in oils from cereals, in nuts, beans, in sunflower seeds, sesame seeds, in corn, soybeans, peanuts, pumpkin. Omega-6 deficiency is rare as this fatty acid is found in many foods. In addition to those already mentioned, beef and poultry are good sources of linoleic acid.
A lack of (linolenic acid) is associated with the development of diseases such as chronic inflammation (from inflammation in the intestines to rheumatoid arthritis), cardiovascular disease, distraction and hyperactivity. Alpha-linolenic acid is found in large quantities in pumpkin, flaxseed, rapeseed, soybean oils, some leafy vegetables, but most of all in oily sea fish.
But it is not enough just to consume omega-3 and omega-6 regularly. It is important to maintain a specific ratio between these fatty acids. Nutritionists suggest the optimal ratio of omega-3: omega-6 - 1 to 2. Meanwhile, in practice, for many, this ratio is 1:25. In order to achieve a more beneficial ratio, it is important to reduce the amount of omega-6 in the diet and increase omega-3. This can be easily achieved by reducing the consumption of meat, dairy and refined foods. But at the same time, on the contrary, increase the portions of fish (preferably salmon), flaxseed oil, walnuts, green leafy vegetables.
"Bad" fats
Partial hydrogenation of unsaturated fatty acids (used in the food industry) leads to the formation of trans fats. They retain a solid or semi-solid consistency even at room temperature. High amounts of trans fatty acids are found in cookies, cakes, crackers, and chips. In cooking, this substance is used to extend the shelf life of confectionery. But trans fats lead to an increase in blood cholesterol levels, which can further trigger the development of coronary heart disease.
One of the most important functions of fats is that lipids are the main component of membranes in all cells of the human body. But different types fats - unsaturated, monounsaturated and polyunsaturated - are needed in different amounts. Cells primarily need polyunsaturated and partially monounsaturated fats. These lipids allow the membranes to remain flexible and flexible. When the level of saturated fat is too high, cell membranes become rigid, their functional capacity decreases, and they lose their ability to protect the inner parts of cells.
Monounsaturated Fat:
- olive oil;
- peanut butter;
- avocado;
- seeds;
- nuts.
Polyunsaturated fats:
- corn oil;
- soybean oil;
- linseed oil;
- oily fish;
- walnuts;
- some seeds.
Saturated Fat:
- fatty red meat;
- dairy products;
- butter;
- palm oil;
- coconut oil;
- dairy desserts.
Trans fats:
- confectionery;
- crisps;
- whitish.
The human body is an amazing machine capable of learning to survive with any type of diet, adapting to a variety of diets. And this ability was inherited by modern man from his ancestors, whose frequency of food intake and diet depended on subjective factors (successful hunting or, for example, the quality of the harvest of berries in the vicinity).
A modern person gets calories in much larger quantities and without much energy consumption. And all the difficulties with nutrition that remain for Homo Sapiens is to correctly combine those important for life, to ensure the balance of the intake of proteins, fats and carbohydrates. But even this, alas, many do not succeed.
The moment a person bites off a slice of meat, pie or vegetable, a complex process of digestion starts. The body processes every piece of food taken, breaking it down into the smallest organic matter. A complex of chemical reactions transform food from a familiar form for humans into separate chemical components that serve as "fuel" for many processes. Proteins, carbohydrates and fats have a long metabolic pathway. And in each macronutrient it is unique, unique.
Provided that these three substances are presented in the required amount, then, first of all, sugars and fats are used as a source of energy, because there is a relationship between the metabolism of carbohydrates and lipids. Proteins at this time serve as "raw materials" for muscles, hormones and other biological "equipment".
Protein obtained from food is broken down by the body into pieces (amino acids), which are then used to create new proteins with specific functions. They speed up some of the chemical reactions in the body and promote inter-cell communication. With a deficiency of carbohydrates and fats, they serve as a source of energy.
Lipids typically provide nearly half of the energy needed. The fat obtained from food is broken down into fatty acids, which "travel" in the blood. Triglycerides are stored in fat cells and have unlimited potential.
But carbohydrates can be stored in the body only in small quantities. The body also breaks down sugars obtained from food into small parts and, already in the form of glucose, they enter the liver and circulatory system, affecting the "sweetness" of the blood. As the researchers convince, the body is more willing to accept and "digest" a larger portion of sugars than fat. Residual carbohydrates (those that the liver cannot contain to make glucose) are converted into "long-term storage" fat. When the body is deficient in carbohydrates, it uses fat from the bins for energy.
Although lipids are a good source of energy for almost the entire body, there are several types of cells that have specific needs. Top of this list are brain cells. They work easily if the diet consists solely of carbohydrates, but almost cannot work only on fats. A low-carb diet is dangerous for the brain.
Protein deficiency is no less dangerous: when there is a shortage of proteins, the body begins to "eat" the cells of its own muscles.
Instead of an afterword
Macronutrients serve as building blocks. Healthy fats, in particular, take care of the preservation of cell membranes and prevent inflammation. A menu made up of healthy foods is a guarantee that the body will receive complex carbohydrates, "good" fats and proteins in the required amount. Besides, balanced diet - a full range of nutrients, minerals, vitamins, and important for health. It is the interconnection of the elements of the full spectrum of nutrients that will protect against diseases and early aging, provide the necessary energy and strength. Well, and of course, do not forget about 6-8 glasses of water recommended by nutritionists, in which our life is.
| Product (100 g) | Protein | Fats | Carbohydrates |
|---|---|---|---|
| Vegetables | |||
| Potatoes | 1,9 | 0,1 | 19,8 |
| Carrot | 1,2 | 0,2 | 7,1 |
| Cabbage | 1,7 | – | 5,3 |
| Cucumbers | 0,8 | – | 3 |
| Zucchini | 0,5 | 0,2 | 5,6 |
| Tomatoes | 0,5 | – | 4,3 |
| Sweet pepper | 1,2 | – | 4,6 |
| Spinach | 3 | – | 2,3 |
| Fruits and berries | |||
| Mandarin | 0,7 | – | 8,5 |
| Lemon | 0,8 | – | 3,6 |
| An Apple | 0,5 | – | 11,4 |
| Peach | 0,8 | – | 10,5 |
| Plum | 0,7 | – | 9,8 |
| Strawberry | 1,7 | – | 8,1 |
| Gooseberry | 0,7 | – | ,9 |
| Dates | 2,4 | – | 72,2 |
| Banana | 1,4 | – | 22,3 |
| Porridge | |||
| Buckwheat | 12,5 | 2,5 | 68,1 |
| Rice | 7,1 | 0,5 | 73,6 |
| Oatmeal | 13,2 | 6,1 | 65,6 |
| Pearl barley | 3,4 | 1,2 | 73,6 |
| Dairy products | |||
| Cottage cheese p / w | 16,8 | 9,1 | 1,4 |
| Milk | 25,5 | 25,1 | 39,3 |
| Yoghurt 1.5% | 5 | 1,4 | 3,6 |
| Kefir | 2,7 | 3,1 | 4,2 |
| Animal products | |||
| Chicken breast | 20,7 | 8,6 | 0,5 |
| Beef | 18,8 | 12,5 | – |
| Pork n / f | 16,3 | 27,9 | – |
| Egg | 12,6 | 11,6 | 0,8 |
| Fish | |||
| Trout | 24,2 | 7,2 | – |
| Red caviar (sturgeon) | 28,8 | 9,8 | – |
| River perch | 18,6 | 0,9 | – |
| Herring | 17,8 | 19,4 | – |
| Mushrooms | |||
| Champignon | 3,1 | 0,3 | 3,3 |
| Porcini mushrooms (fresh) | 3,2 | 0,5 | 1,7 |
| Nuts and seeds | |||
| Peanut | 26,2 | 45,1 | 9,6 |
| Walnuts | 13,7 | 61,2 | 10,1 |
| Sunflower seeds | 20,6 | 52,8 | 5,1 |
| Bakery products | |||
| Rye bread | 4,6 | 0,6 | 49,7 |
| Wheat bread | 7,8 | 2,3 | 53,3 |
| Pasta | 11 | 0,8 | 74,1 |
| Legumes | |||
| Beans | 22,4 | 1,6 | 54,4 |
| Peas | 23 | 1,7 | 57,6 |
| Beans | 5,9 | 0,2 | 8,2 |
| Lentils | 24,7 | 1,2 | 53,8 |
| The drinks | |||
| Tea | – | – | 0,3 |
| Coffee | 0,1 | – | – |
| Cocoa | 6,8 | 3,9 | 83,6 |
| Sweets | |||
| Marshmallow | 0,8 | – | 78,3 |
| Black chocolate | 5,3 | 35,2 | 52,5 |
| Milk chocolate | 6,8 | 35,6 | 52,3 |
| Vanilla ice cream | 3,5 | 11 | 23,6 |
| Honey | 0,8 | – | 80,3 |
| Marmalade | – | – | 98,9 |