Carbohydrates are organic compounds made up of carbon and oxygen. There are simple carbohydrates, or monosaccharides, such as glucose, and complex, or polysaccharides, which are divided into lower, containing few residues. simple carbohydrates, such as disaccharides, and higher, having very large molecules from many residues of simple carbohydrates. In animal organisms, the carbohydrate content is about 2% dry weight.

The average daily requirement of an adult in carbohydrates is 500 g, and with intensive muscular work - 700-1000 g.

The amount of carbohydrates per day should be 60% by weight, and 56% by weight. total food.

Glucose is contained in the blood, in which its amount is maintained at a constant level (0.1-0.12%). After absorption in the intestine, monosaccharides are delivered by the blood to where synthesis of glycogen from monosaccharides, which is part of the cytoplasm, takes place. Glycogen stores are stored mainly in the muscles and in the liver.

The total amount of glycogen in a human body weighing 70 kg is approximately 375 g, of which 245 g is contained in the muscles, 110 g (up to 150 g) in the liver, 20 g in the blood and other body fluids. In the body of a trained person, glycogen is 40 -50% more than untrained.

Carbohydrates - main source energy for the life and work of the body.

In the body, under oxygen-free (anaerobic) conditions, carbohydrates break down into lactic acid, releasing energy. This process is called glycolysis. With the participation of oxygen (aerobic conditions), they are split into carbon dioxide and, while releasing much more energy. big biological significance has an anaerobic breakdown of carbohydrates with the participation of phosphoric acid - phosphorylation.

Phosphorylation of glucose occurs in the liver with the participation of enzymes. The source of glucose can be amino acids and fats. In the liver, from pre-phosphorylated glucose, huge polysaccharide molecules, glycogen, are formed. The amount of glycogen in the human liver depends on the nature of nutrition and muscle activity. With the participation of other enzymes in the liver, glycogen is broken down to glucose - sugar formation. The breakdown of glycogen in the liver and skeletal muscles during fasting and muscular work is accompanied by simultaneous synthesis of glycogen. Glucose, formed in the liver, enters and is delivered with it to all cells and tissues.

Only a small part of proteins and fats releases energy in the process of desmolytic breakdown and, therefore, serves as a direct source of energy. A significant part of the proteins and fats, even before complete disintegration, is first converted into carbohydrates in the muscles. In addition, from the digestive canal, the products of hydrolysis of proteins and fats enter the liver, where amino acids and fats are converted into glucose. This process is referred to as gluconeogenesis. The main source of glucose formation in the liver is glycogen, a much smaller part of glucose is obtained by gluconeogenesis, during which the formation of ketone bodies is delayed. Thus, carbohydrate metabolism significantly affects the metabolism, and water.

When glucose consumption by working muscles increases 5-8 times, glycogen is formed in the liver from fats and proteins.

Unlike proteins and fats, carbohydrates break down easily, so they are quickly mobilized by the body at high energy costs (muscle work, emotions of pain, fear, anger, etc.). The breakdown of carbohydrates keeps the body stable and is the main source of energy for the muscles. Carbohydrates are essential for the normal functioning of the nervous system. A decrease in blood sugar leads to a drop in body temperature, weakness and fatigue of muscles, and disorders of nervous activity.

In tissues, only a very small part of the glucose delivered by the blood is used with the release of energy. The main source of carbohydrate metabolism in tissues is glycogen, previously synthesized from glucose.

During the work of the muscles - the main consumers of carbohydrates - the glycogen reserves in them are used, and only after these reserves are completely used up, the direct use of glucose delivered to the muscles by the blood begins. This consumes glucose, formed from glycogen stores in the liver. After work, the muscles renew their supply of glycogen, synthesizing it from blood glucose, and the liver - due to absorbed monosaccharides in the digestive tract and the breakdown of proteins and fats.

For example, with an increase in blood glucose above 0.15-0.16% due to its abundant content in food, which is referred to as food hyperglycemia, it is excreted from the body with urine - glycosuria.

On the other hand, even with prolonged fasting, the level of glucose in the blood does not decrease, since glucose enters the blood from tissues during the breakdown of glycogen in them.

Brief description of the composition, structure and ecological role of carbohydrates

Carbohydrates are organic substances consisting of carbon, hydrogen and oxygen, having the general formula C n (H 2 O) m (for the vast majority of these substances).

The value of n is either equal to m (for monosaccharides), or greater than it (for other classes of carbohydrates). The above general formula does not correspond to deoxyribose.

Carbohydrates are divided into monosaccharides, di (oligo) saccharides and polysaccharides. Below is a brief description individual representatives each class of carbohydrates.

Brief description of monosaccharides

Monosaccharides are carbohydrates whose general formula is C n (H 2 O) n (the exception is deoxyribose).

Classifications of monosaccharides

Monosaccharides are quite extensive and complex group compounds, so they have complex classification on various grounds:

1) according to the number of carbon contained in a monosaccharide molecule, tetroses, pentoses, hexoses, heptoses are distinguished; greatest practical value have pentoses and hexoses;

2) according to functional groups, monosaccharides are divided into ketoses and aldoses;

3) according to the number of atoms contained in the cyclic monosaccharide molecule, pyranoses (contain 6 atoms) and furanoses (contain 5 atoms) are distinguished;

4) based on the spatial arrangement of the "glucosidic" hydroxide (this hydroxide is obtained by attaching a hydrogen atom to the oxygen of the carbonyl group), monosaccharides are divided into alpha and beta forms. Let's take a look at some of the most important monosaccharides of greatest biological and ecological importance in nature.

Brief description of pentoses

Pentoses are monosaccharides, the molecule of which contains 5 carbon atoms. These substances can be both open-chain and cyclic, aldoses and ketoses, alpha and beta compounds. Among them, ribose and deoxyribose are of the most practical importance.

ribose formula in general view C 5 H 10 O 5. Ribose is one of the substances from which ribonucleotides are synthesized, from which various ribonucleic acids (RNA) are subsequently obtained. Therefore, the furanose (5-membered) alpha form of ribose is of greatest importance (in formulas, RNA is depicted in the form of a regular pentagon).

The formula of deoxyribose in general form is C 5 H 10 O 4. Deoxyribose is one of the substances from which deoxyribonucleotides are synthesized in organisms; the latter are the starting materials for the synthesis of deoxyribo nucleic acids(DNA). Therefore, the cyclic alpha form of deoxyribose, which lacks a hydroxide at the second carbon atom in the cycle, is of greatest importance.

The open-chain forms of ribose and deoxyribose are aldoses, that is, they contain 4 (3) hydroxide groups and one aldehyde group. With the complete breakdown of nucleic acids, ribose and deoxyribose are oxidized to carbon dioxide and water; This process is accompanied by the release of energy.

Brief description of hexoses

Hexoses are monosaccharides whose molecules contain six carbon atoms. The general formula of hexoses is C 6 (H 2 O) 6 or C 6 H 12 O 6. All varieties of hexoses are isomers corresponding to the above formula. Among hexoses, there are ketoses, and aldoses, and alpha and beta forms of molecules, open-chain and cyclic forms, pyranose and furanose cyclic forms of molecules. Of greatest importance in nature are glucose and fructose, which are briefly discussed below.

1. Glucose. Like any hexose, it has the general formula C 6 H 12 O 6 . It belongs to aldoses, i.e. it contains an aldehyde functional group and 5 hydroxide groups (characteristic of alcohols), therefore, glucose is a polyatomic aldehyde alcohol (these groups are contained in an open-chain form, the aldehyde group is absent in the cyclic form, since it turns into a hydroxide a group called "glucosidic hydroxide"). The cyclic form can be either five-membered (furanose) or six-membered (pyranose). The most important in nature is the pyranose form of the glucose molecule. The cyclic pyranose and furanose forms can be either alpha or beta, depending on the location of the glucosidic hydroxide relative to other hydroxide groups in the molecule.

According to its physical properties, glucose is a white crystalline solid with a sweet taste (the intensity of this taste is similar to sucrose), highly soluble in water and capable of forming supersaturated solutions (“syrups”). Since the glucose molecule contains asymmetric carbon atoms (i.e., atoms connected to four different radicals), glucose solutions have optical activity, therefore, D-glucose and L-glucose are distinguished, which have different biological activity.

From a biological point of view, the ability of glucose to easily oxidize according to the scheme is most important:

С 6 Н 12 O 6 (glucose) → (intermediate stages) → 6СO 2 + 6Н 2 O.

Glucose is a biologically important compound, as it is used by the body through its oxidation as a universal nutrient and a readily available source of energy.

2. Fructose. This is ketosis, its general formula is C 6 H 12 O 6, that is, it is an isomer of glucose, it is characterized by open-chain and cyclic forms. The most important is beta-B-fructofuranose or beta-fructose for short. Sucrose is made from beta-fructose and alpha-glucose. Under certain conditions, fructose is able to turn into glucose during the isomerization reaction. Fructose is similar in physical properties to glucose, but sweeter than it.

Brief description of disaccharides

Disaccharides are products of the reaction of dicondensation of the same or different molecules of monosaccharides.

Disaccharides are one of the varieties of oligosaccharides (a small number of monosaccharide molecules (same or different) are involved in the formation of their molecules.

The most important representative of disaccharides is sucrose (beet or cane sugar). Sucrose is a product of the interaction of alpha-D-glucopyranose (alpha-glucose) and beta-D-fructofuranose (beta-fructose). Its general formula is C 12 H 22 O 11. Sucrose is one of the many isomers of disaccharides.

It's white crystalline substance, which exists in various states: coarse-grained ("sugar heads"), fine-crystalline (granulated sugar), amorphous (powdered sugar). It dissolves well in water, especially in hot water (compared to hot water, the solubility of sucrose in cold water is relatively low), so sucrose is able to form "supersaturated solutions" - syrups that can "candied", i.e., fine-crystalline suspensions are formed. Concentrated solutions of sucrose are able to form special glassy systems - caramel, which is used by humans to obtain certain varieties of sweets. Sucrose is a sweet substance, but the intensity of the sweet taste is less than that of fructose.

The most important chemical property of sucrose is its ability to hydrolyze, in which alpha-glucose and beta-fructose are formed, which enter into carbohydrate metabolism reactions.

For humans, sucrose is one of the most important food products, as it is a source of glucose. However, excessive consumption of sucrose is harmful, because it leads to a violation of carbohydrate metabolism, which is accompanied by the appearance of diseases: diabetes, dental diseases, obesity.

General characteristics of polysaccharides

Polysaccharides are called natural polymers, which are products of the polycondensation reaction of monosaccharides. As monomers for the formation of polysaccharides, pentoses, hexoses and other monosaccharides can be used. In practical terms, the hexose polycondensation products are most important. Polysaccharides are also known, the molecules of which contain nitrogen atoms, such as chitin.

Hexose-based polysaccharides have the general formula (C 6 H 10 O 5)n. They are insoluble in water, while some of them are able to form colloidal solutions. The most important of these polysaccharides are various varieties of vegetable and animal starches (the latter are called glycogens), as well as varieties of cellulose (fiber).

General characteristics of the properties and ecological role of starch

Starch is a polysaccharide that is a product of the polycondensation reaction of alpha-glucose (alpha-D-glucopyranose). By origin, vegetable and animal starches are distinguished. Animal starches are called glycogens. Although, in general, starch molecules have a common structure, the same composition, but the individual properties of starch obtained from different plants are different. So, potato starch is different from corn starch, etc. But all varieties of starch have common properties. These are solid, white, finely crystalline or amorphous substances, “brittle” to the touch, insoluble in water, but in hot water they are able to form colloidal solutions that retain their stability even when cooled. Starch forms both sols (for example, liquid jelly) and gels (for example, jelly prepared with a high starch content is a gelatinous mass that can be cut with a knife).

The ability of starch to form colloidal solutions is associated with the globularity of its molecules (the molecule is, as it were, rolled into a ball). Upon contact with warm or hot water, water molecules penetrate between the turns of starch molecules, the molecule increases in volume and the density of the substance decreases, which leads to the transition of starch molecules to a mobile state characteristic of colloidal systems. The general formula of starch is: (C 6 H 10 O 5) n, the molecules of this substance have two varieties, one of which is called amylose (there are no side chains in this molecule), and the other is amylopectin (the molecules have side chains in which the connection occurs through 1 - 6 carbon atoms by an oxygen bridge).

The most important chemical property that determines the biological and ecological role of starch is its ability to undergo hydrolysis, ultimately forming either the disaccharide maltose or alpha-glucose (this is the final product of starch hydrolysis):

(C 6 H 10 O 5) n + nH 2 O → nC 6 H 12 O 6 (alpha-glucose).

The process takes place in organisms under the action of a whole group of enzymes. Due to this process, the body is enriched with glucose - the most important nutrient compound.

A qualitative reaction to starch is its interaction with iodine, in which a red-violet color occurs. This reaction is used to detect starch in various systems.

The biological and ecological role of starch is quite large. This is one of the most important storage compounds in plant organisms, for example, in plants of the cereal family. For animals, starch is the most important trophic substance.

Brief description of the properties and ecological and biological role of cellulose (fiber)

Cellulose (fiber) is a polysaccharide, which is a product of the polycondensation reaction of beta-glucose (beta-D-glucopyranose). Its general formula is (C 6 H 10 O 5) n. Unlike starch, cellulose molecules are strictly linear and have a fibrillar (“filamentous”) structure. The difference in the structures of starch and cellulose molecules explains the difference in their biological and ecological roles. Cellulose is neither a reserve nor a trophic substance, since it is not able to be digested by most organisms (the exception is some types of bacteria that can hydrolyze cellulose and assimilate beta-glucose). Cellulose is not capable of forming colloidal solutions, but it can form mechanically strong filamentous structures that provide protection for individual cell organelles and the mechanical strength of various plant tissues. Like starch, cellulose is hydrolyzed under certain conditions, and the end product of its hydrolysis is beta-glucose (beta-D-glucopyranose). In nature, the role of this process is relatively small (but it allows the biosphere to “assimilate” cellulose).

(C 6 H 10 O 5) n (fiber) + n (H 2 O) → n (C 6 H 12 O 6) (beta-glucose or beta-D-glucopyranose) (with incomplete hydrolysis of fiber, the formation of a soluble disaccharide is possible - cellobiose).

AT natural conditions fiber (after the death of plants) undergoes decomposition, as a result of which the formation of various compounds is possible. Due to this process, humus (an organic component of the soil) is formed, different kinds coal (oil and coal are formed from the dead remains of various animal and plant organisms in the absence, that is, under anaerobic conditions, the whole complex of organic substances, including carbohydrates, participates in their formation).

The ecological and biological role of fiber is that it is: a) protective; b) mechanical; c) a formative compound (for some bacteria it performs a trophic function). The dead remains of plant organisms are a substrate for some organisms - insects, fungi, various microorganisms.

Brief description of the ecological and biological role of carbohydrates

Summarizing the above material related to the characteristics of carbohydrates, we can draw the following conclusions about their ecological and biological role.

1. They perform a building function both in cells and in the body as a whole due to the fact that they are part of the structures that form cells and tissues (this is especially true for plants and fungi), for example, cell membranes, various membranes, etc. in addition, carbohydrates are involved in the formation of biologically necessary substances that form a number of structures, for example, in the formation of nucleic acids that form the basis of chromosomes; carbohydrates are part of complex proteins - glycoproteins, which are of particular importance in the formation cell structures and intercellular substance.

2. The most important function of carbohydrates is the trophic function, which consists in the fact that many of them are food products of heterotrophic organisms (glucose, fructose, starch, sucrose, maltose, lactose, etc.). These substances, in combination with other compounds, form food products used by humans (various cereals; fruits and seeds of individual plants, which include carbohydrates in their composition, are food for birds, and monosaccharides, entering into a cycle of various transformations, contribute to the formation of both their own carbohydrates, characteristic for given organism, and other organo-biochemical compounds (fats, amino acids (but not their proteins), nucleic acids, etc.).

3. Carbohydrates are also characterized by an energy function, which consists in the fact that monosaccharides (in particular glucose) are easily oxidized in organisms (the end product of oxidation is CO 2 and H 2 O), while a large amount of energy is released, accompanied by the synthesis of ATP.

4. They also have a protective function, consisting in the fact that structures (and certain organelles in the cell) arise from carbohydrates that protect either the cell or the body as a whole from various damages, including mechanical ones (for example, chitinous covers of insects that form external skeleton, cell membranes of plants and many fungi, including cellulose, etc.).

5. Big role play the mechanical and shaping functions of carbohydrates, which are the ability of structures formed either by carbohydrates, or in combination with other compounds, to give the body certain form and make them mechanically strong; thus, the cell membranes of the mechanical tissue and vessels of the xylem create the frame (internal skeleton) of woody, shrubby and herbaceous plants, the external skeleton of insects is formed by chitin, etc.

Brief description of carbohydrate metabolism in a heterotrophic organism (on the example of a human body)

An important role in understanding metabolic processes is played by knowledge of the transformations that carbohydrates undergo in heterotrophic organisms. In the human body, this process is characterized by the following schematic description.

Carbohydrates in food enter the body through the mouth. Monosugar in digestive system practically do not undergo transformations, disaccharides are hydrolyzed to monosaccharides, and polysaccharides undergo quite significant transformations (this applies to those polysaccharides that are consumed by the body, and carbohydrates that are not food substances, for example, cellulose, some pectins, are removed from the body with feces masses).

AT oral cavity food is crushed and homogenized (becomes more homogeneous than before entering it). Food is affected by saliva secreted by the salivary glands. It contains ptyalin and has alkaline reaction medium, due to which the primary hydrolysis of polysaccharides begins, leading to the formation of oligosaccharides (carbohydrates with a small n value).

Part of the starch can even turn into disaccharides, which can be seen with prolonged chewing of bread (sour black bread becomes sweet).

Chewed food, richly treated with saliva and crushed by teeth, enters the stomach through the esophagus in the form of a food lump, where it is exposed to gastric juice with an acid reaction of the medium containing enzymes that act on proteins and nucleic acids. Almost nothing happens in the stomach with carbohydrates.

Then the food gruel enters the first section of the intestine (small intestine), beginning with the duodenum. It receives pancreatic juice (pancreatic secretion), which contains a complex of enzymes that promote the digestion of carbohydrates. Carbohydrates are converted into monosaccharides, which are water soluble and absorbable. Dietary carbohydrates are finally digested in the small intestine, and in the part where the villi are contained, they are absorbed into the blood and enter the circulatory system.

With the blood flow, monosaccharides are carried to various tissues and cells of the body, but first all the blood passes through the liver (where it is cleared of harmful metabolic products). In the blood, monosaccharides are present mainly in the form of alpha-glucose (but other hexose isomers, such as fructose, are also possible).

If blood glucose is less than normal, then part of the glycogen contained in the liver is hydrolyzed to glucose. An excess of carbohydrates characterizes a serious human disease - diabetes.

From the blood, monosaccharides enter the cells, where most of them are spent on oxidation (in mitochondria), in which ATP is synthesized, which contains energy in a “convenient” form for the body. ATP is used for various processes that require energy (synthesis of substances necessary for the body, the implementation of physiological and other processes).

Part of the carbohydrates in food is used to synthesize the carbohydrates of a given organism, which are required for the formation of cell structures, or compounds necessary for the formation of substances of other classes of compounds (this is how fats, nucleic acids, etc. can be obtained from carbohydrates). The ability of carbohydrates to turn into fats is one of the causes of obesity - a disease that entails a complex of other diseases.

Therefore, the consumption of excess carbohydrates is harmful to human body that must be taken into account when organizing a balanced diet.

In plant organisms that are autotrophs, carbohydrate metabolism is somewhat different. Carbohydrates (monosugar) are synthesized by the body itself from carbon dioxide and water using solar energy. Di-, oligo- and polysaccharides are synthesized from monosaccharides. Part of the monosaccharides is included in the synthesis of nucleic acids. Plant organisms use a certain amount of monosaccharides (glucose) in the processes of respiration for oxidation, in which (as in heterotrophic organisms) ATP is synthesized.

Carbohydrates in food.

Carbohydrates are basic and easy available source energy for the human body. All carbohydrates are complex molecules consisting of carbon (C), hydrogen (H) and oxygen (O), the name comes from the words "coal" and "water".

Of the main sources of energy known to us, three can be distinguished:

Carbohydrates (up to 2% of reserves)
- fats (up to 80% of reserves)
- proteins (up to 18% of stocks )

Carbohydrates are the fastest fuel, which is primarily used for energy production, but their reserves are very small (on average 2% of the total). their accumulation requires a lot of water (to retain 1g of carbohydrates, 4g of water is needed), and water is not required for the deposition of fats.

The main stores of carbohydrates are stored in the body in the form of glycogen (a complex carbohydrate). Most of its mass is contained in the muscles (about 70%), the rest in the liver (30%).
You can find out all other functions of carbohydrates as well as their chemical structure

Carbohydrates in foods are classified as follows.

Types of carbohydrates.

Carbohydrates, in a simple classification, are divided into two main classes: simple and complex. Simple, in turn, consist of monosaccharides and oligosaccharides, complex of polysaccharides and fibrous.

Simple carbohydrates.

Monosaccharides

Glucose("grape sugar", dextrose).
Glucose- the most important of all monosaccharides, since it is the structural unit of most dietary di- and polysaccharides. In the human body, glucose is the main and most versatile source of energy for metabolic processes. All cells of the animal body have the ability to absorb glucose. At the same time, the ability to use other energy sources - for example, free fatty acid and glycerin, fructose or lactic acid - not all cells of the body possess, but only some of their types. In the process of metabolism, they are broken down into individual molecules of monosaccharides, which, in the course of multi-stage chemical reactions, are converted into other substances and ultimately oxidized to carbon dioxide and water - used as "fuel" for cells. Glucose is an essential component of metabolism carbohydrates. With a decrease in its level in the blood or a high concentration and the inability to use, as happens with diabetes, drowsiness occurs, loss of consciousness (hypoglycemic coma) may occur.
Glucose "in its pure form", as a monosaccharide, is found in vegetables and fruits. Especially rich in glucose are grapes - 7.8%, cherries, cherries - 5.5%, raspberries - 3.9%, strawberries - 2.7%, plums - 2.5%, watermelon - 2.4%. Of vegetables, the most glucose is found in pumpkin - 2.6%, in white cabbage- 2.6%, in carrots - 2.5%.
Glucose is less sweet than the most famous disaccharide, sucrose. If we take the sweetness of sucrose as 100 units, then the sweetness of glucose will be 74 units.

Fructose(fruit sugar).
Fructose is one of the most common carbohydrates fruits. Unlike glucose, it can pass from the blood into tissue cells without the participation of insulin (a hormone that lowers blood glucose levels). For this reason, fructose is recommended as the safest source. carbohydrates for diabetic patients. Part of the fructose enters the liver cells, which turn it into a more universal "fuel" - glucose, so fructose is also able to increase blood sugar, albeit to a much greater extent. lesser degree than other simple sugars. Fructose is more easily converted into fat than glucose. The main advantage of fructose is that it is 2.5 times sweeter than glucose and 1.7 times sweeter than sucrose. Its use instead of sugar can reduce overall intake carbohydrates.
The main sources of fructose in food are grapes - 7.7%, apples - 5.5%, pears - 5.2%, cherries, sweet cherries - 4.5%, watermelons - 4.3%, black currants - 4.2% , raspberries - 3.9%, strawberries - 2.4%, melons - 2.0%. In vegetables, the fructose content is low - from 0.1% in beets to 1.6% in white cabbage. Fructose is found in honey - about 3.7%. Fructose, which has a much higher sweetness than sucrose, has been well proven to not cause tooth decay, which is promoted by sugar consumption.

Galactose(a kind of milk sugar).
Galactose does not occur in free form in products. It forms a disaccharide with glucose - lactose (milk sugar) - the main carbohydrate milk and dairy products.

Oligosaccharides

sucrose(table sugar).
sucrose is a disaccharide (carbohydrate consisting of two components) formed by glucose and fructose molecules. The most common type of sucrose is - sugar. The content of sucrose in sugar is 99.5%, in fact, sugar is pure sucrose.
Sugar is rapidly broken down in the gastrointestinal tract, glucose and fructose are absorbed into the blood and serve as a source of energy and the most important precursor of glycogen and fats. It is often referred to as the "empty calorie carrier" since sugar is pure carbohydrate and does not contain other nutrients, such as, for example, vitamins, mineral salts. Of the vegetable products, the most sucrose is found in beets - 8.6%, peaches - 6.0%, melons - 5.9%, plums - 4.8%, tangerines - 4.5%. In vegetables, except for beets, a significant content of sucrose is noted in carrots - 3.5%. In other vegetables, the sucrose content ranges from 0.4 to 0.7%. In addition to sugar itself, the main sources of sucrose in food are jam, honey, confectionery, sweet drinks, ice cream.

Lactose(milk sugar).
Lactose broken down in the gastrointestinal tract to glucose and galactose by the action of the enzyme lactase. Deficiency of this enzyme in some people leads to milk intolerance. Undigested lactose serves as a good nutrient for the intestinal microflora. At the same time, abundant gas formation is possible, the stomach “swells”. In fermented milk products, most of the lactose is fermented to lactic acid, so people with lactase deficiency can tolerate fermented milk products without unpleasant consequences. In addition, lactic acid bacteria in fermented milk products inhibit the activity of the intestinal microflora and reduce the adverse effects of lactose.
Galactose, formed during the breakdown of lactose, is converted into glucose in the liver. With a congenital hereditary deficiency or absence of an enzyme that converts galactose into glucose, a serious disease develops - galactosemia , which leads to mental retardation.
The lactose content in cow's milk is 4.7%, in cottage cheese - from 1.8% to 2.8%, in sour cream - from 2.6 to 3.1%, in kefir - from 3.8 to 5.1% , in yoghurts - about 3%.

Maltose(malt sugar).
Formed when two glucose molecules combine. Contained in such products as: malt, honey, beer, molasses, bakery and confectionery products made with the addition of molasses.

Athletes should avoid taking glucose in its pure form and foods rich in simple sugars in large quantities, as they trigger the process of fat formation.

Complex carbohydrates.

Complex carbohydrates consist mainly of repeating units of glucose compounds. (glucose polymers)

Polysaccharides

Plant polysaccharides (starch).
Starch- the main of the digested polysaccharides, it is a complex chain consisting of glucose. It accounts for up to 80% of carbohydrates consumed with food. Starch is a complex or "slow" carbohydrate, so it is the preferred source of energy for both weight gain and weight loss. In the gastrointestinal tract, starch is amenable to hydrolysis (decomposition of a substance under the action of water) is broken down into dextrins (starch fragments), and as a result, into glucose and is already absorbed by the body in this form.
The source of starch is vegetable products, mainly cereals: cereals, flour, bread, and potatoes. Cereals contain the most starch: from 60% in buckwheat (kernel) to 70% in rice. Of the cereals, the least starch is found in oatmeal and its processed products: oatmeal, oatmeal "Hercules" - 49%. Pasta contains from 62 to 68% starch, rye flour bread, depending on the variety, from 33% to 49%, wheat bread and other products made from wheat flour - from 35 to 51% starch, flour - from 56 (rye) to 68% (wheat premium). There is also a lot of starch in legumes - from 40% in lentils to 44% in peas. And also it can be noted not a small content of starch in potatoes (15-18%).

Animal polysaccharides (glycogen).
Glycogen-consists of highly branched chains of glucose molecules. After a meal, a large amount of glucose begins to enter the bloodstream and the human body stores excess glucose in the form of glycogen. When blood glucose levels begin to drop (for example, during exercise), the body breaks down glycogen with the help of enzymes, as a result of which glucose levels remain normal and organs (including muscles during exercise) get enough of it for energy production. Glycogen is deposited mainly in the liver and muscles. It is found in small amounts in animal products (2-10% in the liver, 0.3-1% in muscle tissue). The total supply of glycogen is 100-120 g. In bodybuilding, only the glycogen that is contained in muscle tissue matters.

fibrous

dietary fiber (indigestible, fibrous)
Dietary fiber or dietary fiber refers to nutrients that, like water and mineral salts, do not provide the body with energy, but play a huge role in its life. Dietary fiber found primarily in plant-based foods that are low or very low in sugar. It is usually combined with other nutrients.

Types of fiber.

Cellulose and Hemicellulose
Cellulose present in whole wheat flour, bran, cabbage, baby peas, green and waxy beans, broccoli, Brussels sprouts, cucumber skins, peppers, apples, carrots.
Hemicellulose found in bran, cereals, unrefined grains, beets, Brussels sprouts, mustard green shoots.
Cellulose and hemicellulose absorb water, facilitating the activity of the colon. In essence, they "volume" the waste and move it through the large intestine faster. This not only prevents constipation, but also protects against diverticulosis, spasmodic colitis, hemorrhoids, colon cancer and varicose veins.

lignin
This type of fiber is found in cereals used for breakfast, in bran, stale vegetables (when vegetables are stored, the lignin content in them increases and they are less digestible), as well as in eggplant, green beans, strawberries, peas, and radishes.
Lignin reduces the digestibility of other fibers. In addition, it binds to bile acids, helping to lower cholesterol levels and speeding up the passage of food through the intestines.

Gum and Pectin
Comedy found in oatmeal and other oat products, in dried beans.
Pectin present in apples, citrus fruits, carrots, cauliflower and cabbage, dried peas, green beans, potatoes, strawberries, strawberries, fruit drinks.
Gum and pectin affect absorption processes in the stomach and small intestine. By binding to bile acids, they reduce fat absorption and lower cholesterol levels. They delay gastric emptying and, by enveloping the intestines, slow down the absorption of sugar after a meal, which is useful for diabetics, as it reduces the required dose of insulin.

Knowing the types of carbohydrates, and their functions, the following question arises -

What carbohydrates and how much to eat?

In most products, carbohydrates are the main component, therefore, there should not be any problems with obtaining them from food, therefore, carbohydrates make up the bulk of the daily diet of most people.
Carbohydrates that enter our body with food have three metabolic pathways:

1) Glycogenesis(The complex carbohydrate food that enters our gastrointestinal tract is broken down into glucose, and then stored in the form of complex carbohydrates - glycogen in muscle and liver cells, and is used as a backup source of nutrition when the concentration of glucose in the blood is low)
2) Gluconeogenesis(the process of formation in the liver and cortical substance of the kidneys (about 10%) - glucose, from amino acids, lactic acid, glycerol)
3) Glycolysis(breakdown of glucose and other carbohydrates with energy release)

The metabolism of carbohydrates is mainly determined by the presence of glucose in the bloodstream, this important and versatile source of energy in the body. The presence of glucose in the blood depends on the last meal and the nutritional composition of the food. That is, if you recently had breakfast, then the concentration of glucose in the blood will be high if long time abstain from food - low. Less glucose - less energy in the body, this is obvious, which is why there is a breakdown on an empty stomach. At a time when the glucose content in the bloodstream is low, and this is very well observed in morning hours, after a long sleep, during which you did not maintain the level of available glucose in the blood with portions of carbohydrate food, the body is replenished in a state of starvation with the help of glycolysis - 75%, and 25% with the help of gluconeogenesis, that is, the breakdown of complex stored carbohydrates, as well as amino acids, glycerol and lactic acid.
Also, not a lot importance in regulating the concentration of glucose in the blood has a pancreatic hormone - insulin. Insulin is a transport hormone that carries excess glucose to muscle cells and other tissues of the body, thereby regulating the maximum level of glucose in the blood. In overweight people who do not follow their diet, insulin converts excess carbohydrates from food into fat into the body, this is mainly characteristic of fast carbohydrates.
To choose the right carbs of the whole variety of food, such a concept is used as - glycemic index.

Glycemic index is the rate of absorption of carbohydrates from food into the bloodstream and the insulin response of the pancreas. It shows the effect of foods on blood sugar levels. This index is measured on a scale from 0 to 100, it depends on the types of products, different carbohydrates are digested differently, some quickly, and accordingly they will have a high glycemic index, some slowly, the standard for rapid absorption is pure glucose, it has a glycemic index equals 100.

The GI of a product depends on several factors:

- Type of carbohydrates (simple carbohydrates have a high GI, complex carbohydrates have a low GI)
- The amount of fiber (the more it is in food, the lower the GI)
- The way food is processed (for example, GI increases during heat treatment)
- The content of fats and proteins (the more of them in food, the lower the GI)

There are many various tables determining the glycemic index of foods, here is one of them:

The food glycemic index table allows you to take right decisions, choosing which foods to include in your daily diet, and which ones to consciously exclude.
The principle is simple: the higher the glycemic index, the less often you include such foods in your diet. Conversely, the lower the glycemic index, the more often you eat these foods.

However, fast carbohydrates are also useful to us in such important meals as:

- in the morning (after a long sleep, the concentration of glucose in the blood is very low, and it must be replenished as quickly as possible in order to prevent the body from obtaining the necessary energy for life with the help of amino acids, by destroying muscle fibers)
- and after training (when energy costs for intensive physical work significantly reduce the concentration of glucose in the blood, after exercise perfect option take carbohydrates faster to replenish them as quickly as possible and prevent catabolism)

How much to eat carbohydrates?

In bodybuilding and fitness, carbohydrates should be at least 50% of all nutrients (of course, we are not talking about "drying" or losing weight).
There are plenty of reasons to load yourself with a lot of carbohydrates, especially when it comes to whole, unprocessed foods. However, first of all, you must understand that there is a certain limit to the ability of the body to accumulate them. Imagine a gas tank: it can only hold a certain number of liters of gasoline. If you try to pour more into it, the excess will inevitably spill. Once carbohydrate stores are converted to required amount glycogen, the liver begins to process their excess into fat, which is then stored under the skin and in other parts of the body.
The amount of muscle glycogen you can store depends on how much muscle you have. Just as some gas tanks are larger than others, so are the muscles in different people. The more muscular you are, the more glycogen your body can store.
To make sure you're getting the right amount of carbs—no more than you should—calculate your daily carbohydrate intake using the following formula. To build muscle mass per day you should take -

7g of carbohydrates per kilogram of body weight (multiply your weight in kilograms by 7).

By raising your carbohydrate intake to the required level, you must add additional strength training. Plentiful amounts of carbohydrates during bodybuilding will provide you with more energy, allowing you to work out harder and longer and achieve better results.
You can calculate your daily diet by studying this article in more detail.

For those who want to get fat.

Carbohydrates will help you.

As you know, one molecule of fat is four molecules of glucose plus four molecules of water. That is, with an increased intake of carbohydrates in combination with water intake, you will get the expected result. I will note only one thing, it is desirable to consume more complex carbohydrates, because simple carbohydrates can lead to diabetes, hypertension. I hope that with modern nutrition (a set of products in stores), you will not have difficulties along the way. The main thing about carbohydrates is below, thanks to "Wikipedia"

(sugars, saccharides) - organic substances containing a carbonyl group and several hydroxyl groups. The name of the class of compounds comes from the words "carbon hydrates", it was first proposed by K. Schmidt in 1844. The appearance of such a name is due to the fact that the first carbohydrates known to science were described by the gross formula Cx(H2O)y, formally being compounds of carbon and water.
Carbohydrates are a very broad class of organic compounds, among them there are substances with very different properties. This allows carbohydrates to perform a variety of functions in living organisms. Compounds of this class make up about 80% of the dry mass of plants and 2-3% of the mass of animals.

Simple and complex carbohydrates

On the left is D-glyceraldehyde, on the right is dihydroxyacetone.

Carbohydrates are an integral component of the cells and tissues of all living organisms of the flora and fauna, making up (by mass) the main part of the organic matter on Earth. The source of carbohydrates for all living organisms is the process of photosynthesis carried out by plants. According to the ability to hydrolyze into monomers, carbohydrates are divided into two groups: simple (monosaccharides) and complex (disaccharides and polysaccharides). Complex carbohydrates, unlike simple ones, are able to hydrolyze to form monosaccharides, monomers. Simple carbohydrates are easily soluble in water and synthesized in green plants. Complex carbohydrates are products of the polycondensation of simple sugars (monosaccharides), and in the process of hydrolytic cleavage they form hundreds and thousands of monosaccharide molecules.

Monosaccharides

The most common monosaccharide in nature is beta-D-glucose.

Monosaccharides(from the Greek monos - the only one, sacchar - sugar) - the simplest carbohydrates that do not hydrolyze to form simpler carbohydrates - they are usually colorless, easily soluble in water, poorly in alcohol and completely insoluble in ether, solid transparent organic compounds, one of the main groups of carbohydrates, most simple form Sahara. Aqueous solutions have a neutral bsp; pH. Some monosaccharides have a sweet taste. Monosaccharides contain a carbonyl (aldehyde or ketone) group, so they can be considered as derivatives polyhydric alcohols. A monosaccharide with a carbonyl group at the end of the chain is an aldehyde and is called an aldose. At any other position of the carbonyl group, the monosaccharide is a ketone and is called ketose. Depending on the length of the carbon chain (from three to ten atoms), trioses, tetroses, pentoses, hexoses, heptoses, and so on are distinguished. Among them, pentoses and hexoses are the most widespread in nature. Monosaccharides are the building blocks from which disaccharides, oligosaccharides and polysaccharides are synthesized.
In nature, in free form, D-glucose (grape sugar or dextrose, C6H12O6) is the most common - a six-atomic sugar (hexose), a structural unit (monomer) of many polysaccharides (polymers) -disaccharides: (maltose, sucrose and lactose) and polysaccharides (cellulose, starch). Other monosaccharides are generally known as components of di-, oligo- or polysaccharides and are rare in the free state. Natural polysaccharides serve as the main sources of monosaccharides

disaccharides

Maltose (malt sugar) is a natural disaccharide consisting of two glucose residues.

Maltose(malt sugar) - a natural disaccharide consisting of two glucose residues
Disaccharides (from di - two, sacchar - sugar) - complex organic compounds, one of the main groups of carbohydrates, during hydrolysis, each molecule breaks down into two molecules of monosaccharides, are private suchamolygosaccharides. By structure, disaccharides are glycosides, in which two monosaccharide molecules are connected to each other by a glycosidic bond formed as a result of the interaction of hydroxyl groups (two hemiacetal or one hemiacetal and one alcohol). Depending on the structure, disaccharides are divided into two groups: reducing and non-reducing. For example, in the maltose molecule, the second residue of the monosaccharide (glucose) has a free hemiacetal hydroxyl, which gives this disaccharide reducing properties. Disaccharides, along with polysaccharides, are one of the main sources of carbohydrates in the diet of humans and animals.

Oligosaccharides

Rafinose- natural trisaccharide, consisting of residues of D-galactose, D-glucose and D-fructose.
Oligosaccharides- carbohydrates, the molecules of which are synthesized from 2-10 monosaccharide residues connected by glycosidic bonds. Accordingly, they distinguish: disaccharides, trisaccharides and so on. Oligosaccharides consisting of identical monosaccharide residues are called homopolysaccharides, and those consisting of different monosaccharides are called heteropolysaccharides. Disaccharides are the most common among oligosaccharides.
Among natural trisaccharides, raffinose is the most common - a non-reducing oligosaccharide containing residues of fructose, glucose and galactose - found in large quantities in sugar beet and in many other plants.

Polysaccharides

Polysaccharides- the general name of the class of complex high-molecular carbohydrates, the molecules of which consist of tens, hundreds or thousands of monomers - monosaccharides. From the point of view of the general principles of structure in the group of polysaccharides, it is possible to distinguish between homopolysaccharides synthesized from the same type of monosaccharide units and heteropolysaccharides, which are characterized by the presence of two or more types of monomeric residues.
Homopolysaccharides (glycans), consisting of residues of one monosaccharide, can be hexoses or pentoses, that is, hexose or pentose can be used as a monomer. Depending on the chemical nature of the polysaccharide, glucans (from glucose residues), mannans (from mannose), galactans (from galactose) and other similar compounds are distinguished. The group of homopolysaccharides includes organic compounds of plant (starch, cellulose, pectin), animal (glycogen, chitin) and bacterial (dextrans) origin.
Polysaccharides are essential for the life of animals and plants. It is one of the body's main sources of energy resulting from metabolism. Polysaccharides take part in immune processes, provide adhesion of cells in tissues, and are the bulk of organic matter in the biosphere.

On the left is starch, on the right is glycogen.

Starch

(C6H10O5) n is a mixture of two homopolysaccharides: linear - amylose and branched - amylopectin, the monomer of which is alpha-glucose. White amorphous substance, insoluble in cold water, capable of swelling and partially soluble in hot water. Molecular weight 105-107 Daltons. Starch, synthesized by different plants in chloroplasts, under the action of light during photosynthesis, differs somewhat in the structure of grains, the degree of polymerization of molecules, the structure of polymer chains, and physicochemical properties. As a rule, the content of amylose in starch is 10-30%, amylopectin - 70-90%. The amylose molecule contains, on average, about 1,000 glucose residues linked by alpha-1,4 bonds. Separate linear sections of the amylopectin molecule consist of 20-30 such units, and at the branch points of amylopectin, glucose residues are linked by interchain alpha-1,6 bonds. With partial acid hydrolysis starch, polysaccharides of a lower degree of polymerization are formed - dextrins (C6H10O5)p, and with complete hydrolysis - glucose.
Glycogen (C6H10O5) n is a polysaccharide built from alpha-D-glucose residues - the main reserve polysaccharide of higher animals and humans, is contained in the form of granules in the cytoplasm of cells in almost all organs and tissues, however, its largest amount accumulates in muscles and liver. The glycogen molecule is built from branching polyglucoside chains, in a linear sequence of which, glucose residues are connected by alpha-1,4 bonds, and at the branch points by interchain alpha-1,6 bonds. The empirical formula of glycogen is identical to that of starch. In chemical structure, glycogen is close to amylopectin with more pronounced chain branching, therefore it is sometimes called the inaccurate term "animal starch". Molecular weight 105-108 Daltons and above. In animal organisms, it is a structural and functional analogue of the plant polysaccharide - starch. Glycogen forms an energy reserve, which, if necessary, to compensate for a sudden lack of glucose can be quickly mobilized - a strong branching of its molecules leads to the presence of a large number of terminal residues, which provide the ability to quickly cleave the required amount of glucose molecules. Unlike the store of triglycerides (fats), the store of glycogen is not so capacious (in calories per gram). Only glycogen stored in liver cells (hepatocytes) can be converted into glucose to feed the whole body, while hepatocytes are able to store up to 8 percent of their weight in the form of glycogen, which is maximum concentration among all types of cells. The total mass of glycogen in the liver of adults can reach 100-120 grams. In muscles, glycogen is broken down into glucose exclusively for local consumption and accumulates in much lower concentrations (no more than 1% of the total muscle mass), nevertheless general stock in muscles may exceed the reserve accumulated in hepatocytes.

Cellulose (fiber) is the most common structural polysaccharide flora, consisting of alpha-glucose residues presented in beta-pyranose form. Thus, in the cellulose molecule, beta-glucopyranose monomeric units are linearly connected to each other by beta-1,4 bonds. With partial hydrolysis of cellulose, the disaccharide cellobiose is formed, and with complete hydrolysis, D-glucose. In the human gastrointestinal tract, cellulose is not digested, as a set digestive enzymes does not contain beta-glucosidase. However, the presence of an optimal amount of plant fiber in food contributes to the normal formation of feces. Possessing high mechanical strength, cellulose acts as a supporting material for plants, for example, in the composition of wood, its share varies from 50 to 70%, and cotton is almost one hundred percent cellulose.
Chitin is a structural polysaccharide of lower plants, fungi and invertebrates (mainly the corneas of arthropods - insects and crustaceans). Chitin, like cellulose in plants, performs supporting and mechanical functions in the organisms of fungi and animals. The chitin molecule is built from N-acetyl-D-glucosamine residues linked by beta-1,4-glycosium bonds. Chitin macromolecules are unbranched and their spatial arrangement has nothing to do with cellulose.
pectin substances- polygalacturonic acid, found in fruits and vegetables, D-galacturonic acid residues are linked by alpha-1,4-glycosidic bonds. In the presence of organic acids, they are capable of gelation, they are used in the food industry for the preparation of jelly and marmalade. Some pectin substances have an antiulcer effect and are an active component of a number of pharmaceutical preparations, for example, a derivative of the plantain plantaglucid.
Muramine is a polysaccharide, a support-mechanical material of the bacterial cell wall. According to its chemical structure, it is an unbranched chain built from alternating residues of N-acetylglucosamine and N-acetylmuramic acid connected by a beta-1,4-glycosidic bond. Muramin by structural organization(straight chain beta-1,4-polyglucopyranose skeleton) and functional role very close to chitin and cellulose.
Dextran half-saccharides of bacterial origin are synthesized under industrial conditions by microbiological means (by the action of Leuconostoc mesenteroides microorganisms on a sucrose solution) and are used as blood plasma substitutes (the so-called clinical "dextrans": Poliglukin and others).

On the left is D-glyceraldehyde, on the right is L-glyceraldehyde.

Spatial isomerism

Isomerism - the existence of chemical compounds (isomers), identical in composition and molecular weight, differing in the structure or arrangement of atoms in space and, as a result, in properties.
Stereoisomerism of monosaccharides: the isomer of glyceraldehyde in which, when the model is projected onto the plane, the OH group at the asymmetric carbon atom is located on the right side is considered to be D-glyceraldehyde, and the mirror reflection is L-glyceraldehyde. All isomers of monosaccharides are divided into D- and L-forms according to the similarity of the location of the OH group at the last asymmetric carbon atom near the CH2OH group (ketoses contain one less asymmetric carbon atom than aldoses with the same number of carbon atoms). Natural hexoses - glucose, fructose, mannose and galactose - according to stereochemical configurations, are classified as D-series compounds.

Biological role
In living organisms, carbohydrates perform the following functions:
Structural and support functions. Carbohydrates are involved in the construction of various supporting structures. So cellulose is the main structural component cell walls of plants, chitin performs a similar function in fungi, and also provides rigidity to the exoskeleton of arthropods.
Protective role in plants. Some plants have protective formations (thorns, prickles, etc.) consisting of cell walls of dead cells.
plastic function. Carbohydrates are part of complex molecules (for example, pentoses (ribose and deoxyribose) are involved in the construction of ATP, DNA and RNA).
Energy function. Carbohydrates serve as a source of energy: when 1 gram of carbohydrates are oxidized, 4.1 kcal of energy and 0.4 g of water are released.
storage function. Carbohydrates act as reserve nutrients: glycogen in animals, starch and inulin in plants.
osmotic function. Carbohydrates are involved in the regulation of osmotic pressure in the body. Thus, the blood contains 100-110 mg /% glucose, the osmotic pressure of the blood depends on the concentration of glucose.
receptor function. Oligosaccharides are part of the receptive part of many cell receptors or ligand molecules Biosynthesis
Carbohydrates predominate in the daily diet of humans and animals. Herbivores get starch, fiber, sucrose. Carnivores get glycogen from meat.
Animals are unable to synthesize carbohydrates from inorganic substances. They get them from plants with food and use them as the main source of energy obtained in the process of oxidation: In the green leaves of plants, carbohydrates are formed during photosynthesis - a unique biological process of converting inorganic substances into sugars - carbon monoxide (IV) and water, which occurs with the participation chlorophyll due to solar energy: The metabolism of carbohydrates in the human body and higher animals consists of several processes:
Hydrolysis (breakdown) in the gastrointestinal tract of food polysaccharides and disaccharides to monosaccharides, followed by absorption from the intestinal lumen into the bloodstream.
Glycogenogenesis (synthesis) and glycogenolysis (breakdown) of glycogen in tissues, mainly in the liver.
Aerobic (pentose phosphate pathway of glucose oxidation or pentose cycle) and anaerobic (without oxygen consumption) glycolysis are ways of breaking down glucose in the body.
Interconversion of hexoses.
Aerobic oxidation of the product of glycolysis - pyruvate (the final stage of carbohydrate metabolism).
Gluconeogenesis is the synthesis of carbohydrates from non-carbohydrate raw materials (pyruvic, lactic acid, glycerol, amino acids and other organic compounds).
[edit] Key sources
The main sources of carbohydrates from food are: bread, potatoes, pasta, cereals, sweets. The net carbohydrate is sugar. Honey, depending on its origin, contains 70-80% glucose and fructose.
To indicate the amount of carbohydrates in food, a special bread unit is used.
In addition, fiber and pectins that are poorly digested by the human body adjoin the carbohydrate group.

List of the most common carbohydrates

• Monosaccharides

• Oligosaccharides

• sucrose (regular sugar, cane or beet)

• Polysaccharides

• galactomannans

• Glycosaminoglycans (Mucopolysaccharides)

• chondroitin sulfate

• hyaluronic acid

• heparan sulfate

• dermatan sulfate

• keratan sulfate

Glucose is the most important of all monosaccharides, since it is the structural unit of most food di- and polysaccharides. In the process of metabolism, they are broken down into individual molecules of monosaccharides, which, in the course of multi-stage chemical reactions, are converted into other substances and ultimately oxidized to carbon dioxide and water - used as "fuel" for cells. Glucose is an essential component of metabolism carbohydrates. With a decrease in its level in the blood or a high concentration and the inability to use, as happens with diabetes, drowsiness occurs, loss of consciousness (hypoglycemic coma) may occur. Glucose "in its pure form", as a monosaccharide, is found in vegetables and fruits. Especially rich in glucose are grapes - 7.8%, cherries, cherries - 5.5%, raspberries - 3.9%, strawberries - 2.7%, plums - 2.5%, watermelon - 2.4%. Of the vegetables, most glucose is found in pumpkin - 2.6%, in white cabbage - 2.6%, in carrots - 2.5%.

Glucose is less sweet than the most famous disaccharide, sucrose. If we take the sweetness of sucrose as 100 units, then the sweetness of glucose will be 74 units.

Fructose is one of the most common carbohydrates fruits. Unlike glucose, it can penetrate from the blood into tissue cells without the participation of insulin. For this reason, fructose is recommended as the safest source. carbohydrates for diabetic patients. Part of the fructose enters the liver cells, which turn it into a more universal "fuel" - glucose, so fructose is also able to increase blood sugar, although to a much lesser extent than other simple sugars. Fructose is more easily converted into fat than glucose. The main advantage of fructose is that it is 2.5 times sweeter than glucose and 1.7 times sweeter than sucrose. Its use instead of sugar can reduce overall intake carbohydrates.

The main sources of fructose in food are grapes - 7.7%, apples - 5.5%, pears - 5.2%, cherries, sweet cherries - 4.5%, watermelons - 4.3%, black currants - 4.2% , raspberries - 3.9%, strawberries - 2.4%, melons - 2.0%. In vegetables, the fructose content is low - from 0.1% in beets to 1.6% in white cabbage. Fructose is found in honey - about 3.7%. Fructose, which has a much higher sweetness than sucrose, has been well proven to not cause tooth decay, which is promoted by sugar consumption.

Galactose does not occur in free form in products. It forms a disaccharide with glucose - lactose (milk sugar) - the main carbohydrate milk and dairy products.

Lactose is broken down in the gastrointestinal tract to glucose and galactose by the action of an enzyme. lactase. Deficiency of this enzyme in some people leads to milk intolerance. Undigested lactose serves as a good nutrient for the intestinal microflora. At the same time, abundant gas formation is possible, the stomach “swells”. In fermented milk products, most of the lactose is fermented to lactic acid, so people with lactase deficiency can tolerate fermented milk products without unpleasant consequences. In addition, lactic acid bacteria in fermented milk products inhibit the activity of the intestinal microflora and reduce the adverse effects of lactose.

Galactose, formed during the breakdown of lactose, is converted into glucose in the liver. With a congenital hereditary deficiency or absence of an enzyme that converts galactose into glucose, a serious disease develops - galactosemia, which leads to mental retardation.

A disaccharide made up of glucose and fructose molecules is sucrose. The content of sucrose in sugar is 99.5%. That sugar is the "white death", sweet lovers know as well as smokers that a drop of nicotine kills a horse. Unfortunately, both of these common truths often serve as an occasion for jokes than for serious reflection and practical conclusions.

Sugar is rapidly broken down in the gastrointestinal tract, glucose and fructose are absorbed into the blood and serve as a source of energy and the most important precursor of glycogen and fats. It is often referred to as the "empty calorie carrier" since sugar is pure carbohydrate and does not contain other nutrients, such as, for example, vitamins, mineral salts. Of the vegetable products, the most sucrose is found in beets - 8.6%, peaches - 6.0%, melons - 5.9%, plums - 4.8%, tangerines - 4.5%. In vegetables, except for beets, a significant content of sucrose is noted in carrots - 3.5%. In other vegetables, the sucrose content ranges from 0.4 to 0.7%. In addition to sugar itself, the main sources of sucrose in food are jam, honey, confectionery, sweet drinks, ice cream.

When two glucose molecules combine, they form maltose- malt sugar. It contains honey, malt, beer, molasses and bakery and confectionery products made with the addition of molasses.

All polysaccharides found in human food rare exceptions, are polymers of glucose.

Starch is the main digestible polysaccharide. It accounts for up to 80% of food intake. carbohydrates.

The source of starch is vegetable products, mainly cereals: cereals, flour, bread, and potatoes. Cereals contain the most starch: from 60% in buckwheat (kernel) to 70% in rice. Of the cereals, the least starch is found in oatmeal and its processed products: oatmeal, oatmeal "Hercules" - 49%. Pasta contains from 62 to 68% starch, rye flour bread, depending on the variety, from 33% to 49%, wheat bread and other products made from wheat flour - from 35 to 51% starch, flour - from 56 (rye) to 68% (wheat premium). There is also a lot of starch in legumes - from 40% in lentils to 44% in peas. For this reason, dry peas, beans, lentils, chickpeas are classified as legumes. Soybean, which contains only 3.5% starch, and soy flour (10-15.5%) stand apart. Because of high content starch in potatoes (15-18%) in dietology, it is not classified as a vegetable, where the main carbohydrates represented by monosaccharides and disaccharides, and to starchy foods along with cereals and legumes.

In Jerusalem artichoke and some other plants carbohydrates stored in the form of a polymer of fructose - inulin. Food products with the addition of inulin are recommended for diabetes and especially for its prevention (recall that fructose puts less stress on the pancreas than other sugars).

Glycogen- "Animal starch" - consists of highly branched chains of glucose molecules. It is found in small amounts in animal products (2-10% in the liver, 0.3-1% in muscle tissue).

Diabetes mellitus (DM) - endocrine disease, characterized by a syndrome of chronic hyperglycemia, which is a consequence of insufficient production or action of insulin, which leads to a violation of all types of metabolism, primarily carbohydrate, damage to blood vessels (angiopathy), the nervous system (neuropathy), as well as other organs and systems. According to the WHO definition (1985) - diabetes mellitus is a state of chronic ...

Remember!

What substances are called biological polymers?

These are polymers - high-molecular compounds that are part of living organisms. Proteins, some carbohydrates, nucleic acids.

What is the importance of carbohydrates in nature?

Fructose is widely distributed in nature - fruit sugar, which is much sweeter than other sugars. This monosaccharide imparts a sweet taste to plant fruits and honey. The most common disaccharide in nature - sucrose, or cane sugar - consists of glucose and fructose. It is obtained from sugar cane or sugar beets. Starch for plants and glycogen for animals and fungi are a reserve of nutrients and energy. Cellulose and chitin perform structural and protective functions in organisms. Cellulose, or fiber, forms the walls of plant cells. By total mass it ranks first on Earth among all organic compounds. In its structure, chitin is very close to cellulose, which forms the basis of the external skeleton of arthropods and is part of the cell wall of fungi.

Name the proteins you know. What functions do they perform?

Hemoglobin is a blood protein that transports gases in the blood

Myosin - muscle protein, muscle contraction

Collagen - protein of tendons, skin, elasticity, extensibility

Casein is a milk protein

Review questions and assignments

1. What chemical compounds called carbohydrates?

This is large group natural organic compounds. In animal cells, carbohydrates make up no more than 5% of the dry mass, and in some plant cells (for example, tubers or potatoes), their content reaches 90% of the dry residue. Carbohydrates are divided into three main classes: monosaccharides, disaccharides and polysaccharides.

2. What are mono- and disaccharides? Give examples.

Monosaccharides are composed of monomers, low molecular weight organic substances. The monosaccharides ribose and deoxyribose are constituents of nucleic acids. The most common monosaccharide is glucose. Glucose is present in the cells of all organisms and is one of the main sources of energy for animals. If two monosaccharides combine in one molecule, such a compound is called a disaccharide. The most common disaccharide in nature is sucrose, or cane sugar.

3. What simple carbohydrate serves as a monomer of starch, glycogen, cellulose?

4. What organic compounds do proteins consist of?

Long protein chains are built from just 20 different types of amino acids that have overall plan structures, but differing from each other in the structure of the radical. Connecting, amino acid molecules form so-called peptide bonds. The two polypeptide chains that make up the pancreatic hormone insulin contain 21 and 30 amino acid residues. These are some of the shortest "words" in the protein "language". Myoglobin is a protein that binds oxygen in muscle tissue and consists of 153 amino acids. The collagen protein that forms the basis of collagen fibers connective tissue and providing its strength, consists of three polypeptide chains, each of which contains about 1000 amino acid residues.

5. How are secondary and tertiary protein structures formed?

Twisting in the form of a spiral, the protein thread acquires a higher level of organization - a secondary structure. Finally, the polypeptide coils up to form a coil (globule). It is this tertiary structure of the protein that is its biologically active form, which has individual specificity. However, for a number of proteins, the tertiary structure is not final. The secondary structure is a polypeptide chain twisted into a helix. For a stronger interaction in the secondary structure, an intramolecular interaction occurs with the help of –S–S– sulfide bridges between the turns of the helix. This ensures the strength of this structure. The tertiary structure is a secondary spiral structure twisted into globules - compact lumps. These structures provide maximum strength and greater abundance in cells compared to other organic molecules.

6. Name the functions of proteins known to you. How can you explain the existing diversity of protein functions?

One of the main functions of proteins is enzymatic. Enzymes are proteins that catalyze chemical reactions in living organisms. An enzymatic reaction is a chemical reaction that takes place only in the presence of an enzyme. Without an enzyme, not one reaction occurs in living organisms. The work of enzymes is strictly specific, each enzyme has its own substrate, which it cleaves. The enzyme approaches its substrate like a "key to a lock". So, the urease enzyme regulates the breakdown of urea, the amylase enzyme regulates starch, and the protease enzymes regulate proteins. Therefore, for enzymes, the expression "specificity of action" is used.

Proteins also perform various other functions in organisms: structural, transport, motor, regulatory, protective, energy. The functions of proteins are quite numerous, since they underlie the variety of manifestations of life. This is a component biological membranes, transport of nutrients, such as hemoglobin, muscle function, hormonal function, body defense - the work of antigens and antibodies, and other important functions in the body.

7. What is protein denaturation? What can cause denaturation?

Denaturation is a violation of the tertiary spatial structure of protein molecules under the influence of various physical, chemical, mechanical and other factors. Physical factors is temperature, radiation, Chemical Factors is an action on proteins of any chemical substances: solvents, acids, alkalis, concentrated substances, etc. Mechanical factors - shaking, pressure, stretching, twisting, etc.

Think! Remember!

1. Using the knowledge gained in the study of plant biology, explain why there are significantly more carbohydrates in plant organisms than in animals.

Since the basis of life - plant nutrition is photosynthesis, this is the process of formation of complex organic compounds of carbohydrates from simpler inorganic carbon dioxide and water. The main carbohydrate synthesized by plants for air nutrition is glucose, it can also be starch.

2. What diseases can lead to a violation of the conversion of carbohydrates in the human body?

The regulation of carbohydrate metabolism is mainly carried out by hormones and the central nervous system. Glucocorticosteroids (cortisone, hydrocortisone) slow down the rate of glucose transport into tissue cells, insulin accelerates it; adrenaline stimulates the process of sugar formation from glycogen in the liver. The cerebral cortex also belongs to certain role in the regulation of carbohydrate metabolism, since psychogenic factors increase the formation of sugar in the liver and cause hyperglycemia.

The state of carbohydrate metabolism can be judged by the content of sugar in the blood (normally 70-120 mg%). With a sugar load, this value increases, but then quickly reaches the norm. Carbohydrate metabolism disorders occur in various diseases. So, with a lack of insulin, diabetes mellitus occurs.

A decrease in the activity of one of the enzymes of carbohydrate metabolism - muscle phosphorylase - leads to muscular dystrophy.

3. It is known that if there is no protein in the diet, even despite the sufficient caloric content of food, growth stops in animals, the composition of the blood changes and other pathological phenomena occur. What is the reason for such violations?

In the body, there are only 20 different types of amino acids that have a common structural plan, but differ from each other in the structure of the radical, they form different protein molecules, if you do not use proteins, for example, essential ones, which cannot be formed in the body on their own, but must be consumed with food. Thus, if there are no proteins, many protein molecules cannot form within the body itself and pathological changes cannot occur. Growth is controlled by the growth of bone cells, the basis of any cell is protein; hemoglobin is the main protein in the blood, which ensures the transport of the main gases in the body (oxygen, carbon dioxide).

4. Explain the difficulties that arise during organ transplantation, based on the knowledge of the specificity of protein molecules in each organism.

Proteins are the genetic material, since they contain the structure of the DNA and RNA of the body. Thus, proteins have genetic characteristics in each organism, the information of genes is encrypted in them, this is the difficulty when transplanting from alien (unrelated) organisms, since they have different genes, and hence proteins.

Organic compounds that are the main source of energy are called carbohydrates. Most often sugars are found in food plant origin. A carbohydrate deficiency can cause liver dysfunction, and an excess of carbohydrates causes an increase in insulin levels. Let's talk more about sugars.

What are carbohydrates?

These are organic compounds that contain a carbonyl group and several hydroxyl groups. They are part of the tissues of organisms, and are also important component cells. Mono -, oligo - and polysaccharides are isolated, as well as more complex carbohydrates, such as glycolipids, glycosides and others. Carbohydrates are a product of photosynthesis and also the main starting material biosynthesis of other compounds in plants. Due to the wide variety of compounds, this class is able to play multifaceted roles in living organisms. Being oxidized, carbohydrates provide energy to all cells. They are involved in the formation of immunity, and are also part of many cellular structures.

Types of sugars

Organic compounds are divided into two groups - simple and complex. Carbohydrates of the first type are monosaccharides that contain a carbonyl group and are derivatives of polyhydric alcohols. The second group includes oligosaccharides and polysaccharides. The former consist of monosaccharide residues (from two to ten), which are connected by a glycosidic bond. The latter may contain hundreds or even thousands of monomers. The table of carbohydrates that are most often found is as follows:

1. Glucose.
2. Fructose.
3. Galactose.
4. Sucrose.
5. Lactose.
6. Maltose.
7. Raffinose.
8. Starch.
9. Cellulose.
10. Chitin.
11. Muramin.
12. Glycogen.

The list of carbohydrates is extensive. Let's dwell on some of them in more detail.

Simple group of carbohydrates

Depending on the place occupied by the carbonyl group in the molecule, two types of monosaccharides are distinguished - aldoses and ketoses. In the former, the functional group is aldehyde, in the latter, ketone. Depending on the number of carbon atoms in the molecule, the name of the monosaccharide is formed. For example, aldohexoses, aldotetroses, ketotrioses, and so on. These substances are most often colorless, poorly soluble in alcohol, but well in water. Simple carbohydrates in foods are solid, not hydrolyzed during digestion. Some of the representatives have a sweet taste.

Group representatives

What is a simple carbohydrate? First, it is glucose, or aldohexose. It exists in two forms - linear and cyclic. Most accurately describes Chemical properties glucose is the second form. Aldohexose contains six carbon atoms. The substance has no color, but it tastes sweet. It is highly soluble in water. You can find glucose almost everywhere. It exists in the organs of plants and animals, as well as in fruits. In nature, aldohexose is formed during photosynthesis.

Secondly, it is galactose. The substance differs from glucose in the spatial arrangement of the hydroxyl and hydrogen groups at the fourth carbon atom in the molecule. Has a sweet taste. It is found in animal and plant organisms, as well as in some microorganisms.

And the third representative of simple carbohydrates is fructose. The substance is the sweetest sugar produced in nature. It is present in vegetables, fruits, berries, honey. Easily absorbed by the body, quickly excreted from the blood, which leads to its use by patients with diabetes mellitus. Fructose is low in calories and does not cause cavities.

Foods rich in simple sugars

1. 90 g - corn syrup.
2. 50 g - refined sugar.
3. 40.5 g - honey.
4. 24 g - figs.
5. 13 g - dried apricots.
6. 4 g - peaches.

The daily intake of this substance should not exceed 50 g. As for glucose, in this case the ratio will be slightly different:

1. 99.9 g - refined sugar.
2. 80.3 g - honey.
3. 69.2 g - dates.
4. 66.9 g - pearl barley.
5. 61.8 g - oatmeal.
6. 60.4 g - buckwheat.

To calculate the daily intake of a substance, you need to multiply the weight by 2.6. Simple sugars provide energy to the human body and help to cope with various toxins. But we must not forget that with any use there must be a measure, otherwise serious consequences will not be long in coming.

Oligosaccharides

The most common species in this group are disaccharides. What are carbohydrates containing multiple monosaccharides? They are glycosides containing monomers. Monosaccharides are linked by a glycosidic bond, which is formed as a result of the combination of hydroxyl groups. Based on the structure, disaccharides are divided into two types: reducing and non-reducing. The first is maltose and lactose, and the second is sucrose. The reducing type has good solubility and a sweet taste. Oligosaccharides may contain more than two monomers. If monosaccharides are the same, then such a carbohydrate belongs to the group of homopolysaccharides, and if different, then to heteropolysaccharides. An example of the latter type is the trisaccharide raffinose, which contains residues of glucose, fructose and galactose.

lactose, maltose and sucrose

The latter substance dissolves well, has a sweet taste. Sugar cane and beets are a source of disaccharide. In the body, hydrolysis breaks down sucrose into glucose and fructose. The disaccharide is found in large quantities in refined sugar (99.9 g per 100 g of product), in prunes (67.4 g), in grapes (61.5 g) and in other products. With an excess intake of this substance, the ability to turn into fat in almost all nutrients. It also increases the level of cholesterol in the blood. A large amount of sucrose negatively affects the intestinal flora.

Milk sugar, or lactose, is found in milk and its derivatives. The carbohydrate is broken down into galactose and glucose by a special enzyme. If it is not in the body, then milk intolerance occurs. Malt sugar or maltose is an intermediate breakdown product of glycogen and starch. In foods, the substance is found in malt, molasses, honey and sprouted grains. The composition of lactose and maltose carbohydrates is represented by monomer residues. Only in the first case they are D-galactose and D-glucose, and in the second case the substance is represented by two D-glucoses. Both carbohydrates are reducing sugars.

Polysaccharides

What are complex carbohydrates? They differ from each other in several ways:

1. According to the structure of the monomers included in the chain.

2. By the order of finding monosaccharides in the chain.

3. According to the type of glycosidic bonds that connect the monomers.

As with oligosaccharides, homo- and heteropolysaccharides can be distinguished in this group. The first includes cellulose and starch, and the second - chitin, glycogen. Polysaccharides are an important source of energy, which is formed as a result of metabolism. They are involved in immune processes, as well as in the adhesion of cells in tissues.

The list of complex carbohydrates is represented by starch, cellulose and glycogen, we will consider them in more detail. One of the main suppliers of carbohydrates is starch. These are compounds that include hundreds of thousands of glucose residues. Carbohydrate is born and stored in the form of grains in the chloroplasts of plants. Through hydrolysis, starch is converted into water-soluble sugars, which facilitates free movement through the parts of the plant. Once in the human body, carbohydrate begins to break down already in the mouth. AT most starch contains grains of cereals, tubers and bulbs of plants. In the diet, it accounts for about 80% of the total amount of carbohydrates consumed. The largest amount of starch, per 100 g of product, is found in rice - 78 g. Slightly less in pasta and millet - 70 and 69 g. One hundred grams of rye bread includes 48 g of starch, and in the same serving of potatoes its amount reaches only 15 g. The daily requirement of the human body for this carbohydrate is 330-450 g.

Grain products also contain fiber or cellulose. Carbohydrate is part of the cell walls of plants. His contribution is 40-50%. A person is not able to digest cellulose, so there is no necessary enzyme that would carry out the hydrolysis process. But the soft type of fiber, such as potatoes and vegetables, can be well absorbed in the digestive tract. What is the content of this carbohydrate in 100 g of food? Rye and wheat bran are the most fiber-rich foods. Their content reaches 44 g. Cocoa powder includes 35 g of nutritious carbohydrate, and dried mushrooms only 25. Rosehips and ground coffee contain 22 and 21 g. Some of the richest fruits in fiber are apricot and figs. The carbohydrate content in them reaches 18 g. A person needs to eat up to 35 g of cellulose per day. Moreover, the greatest need for carbohydrate occurs at the age of 14 to 50 years.

Glycogen polysaccharide is used as an energy material for the good functioning of muscles and organs. It has no nutritional value, since its content in food is extremely low. The carbohydrate is sometimes called animal starch because of the similarity in structure. In this form, glucose is stored in animal cells (in the largest amount in the liver and muscles). In the liver in adults, the amount of carbohydrate can reach up to 120 g. The leaders in glycogen content are sugar, honey and chocolate. Dates, raisins, marmalade, sweet straws, bananas, watermelon, persimmons and figs can also boast of a high carbohydrate content. The daily norm of glycogen is 100 g per day. If a person is actively involved in sports or performs great job associated with mental activity, the amount of carbohydrate should be increased. Glycogen refers to easily digestible carbohydrates that are stored in reserve, which indicates its use only in case of a lack of energy from other substances.

Polysaccharides also include the following substances:

1. Chitin. It is part of the corneas of arthropods, is present in fungi, lower plants and in invertebrates. The substance plays the role of a support material, and also performs mechanical functions.

2. Muramine. It is present as a support-mechanical material of the bacterial cell wall.

3. Dextrans. Polysaccharides act as substitutes for blood plasma. They are obtained by the action of microorganisms on a solution of sucrose.

4. Pectin substances. Together with organic acids, they can form jelly and marmalade.

Proteins and carbohydrates. Products. List

The human body needs a certain amount of nutrients every day. For example, carbohydrates should be consumed at the rate of 6-8 g per 1 kg of body weight. If a person leads an active lifestyle, then the number will increase. Carbohydrates are almost always found in foods. Let's make a list of their presence per 100 g of food:

1. The largest amount (more than 70 g) is found in sugar, muesli, marmalade, starch and rice.
2. From 31 to 70 g - in flour and confectionery products, in pasta, cereals, dried fruits, beans and peas.
3. Bananas, ice cream, rose hips, potatoes, tomato paste, compotes, coconut, sunflower seeds and cashew nuts contain 16 to 30 g of carbohydrates.
4. From 6 to 15 g - in parsley, dill, beets, carrots, gooseberries, currants, beans, fruits, nuts, corn, beer, pumpkin seeds, dried mushrooms and so on.
5. Up to 5 g of carbohydrates are found in green onions, tomatoes, zucchini, pumpkins, cabbage, cucumbers, cranberries, dairy products, eggs, and so on.

Nutrient should not enter the body less than 100 g per day. Otherwise, the cell will not receive the energy it needs. The brain will not be able to perform its functions of analysis and coordination, therefore, the muscles will not receive commands, which will eventually lead to ketosis.

What are carbohydrates, we told, but, in addition to them, proteins are an indispensable substance for life. They are a chain of amino acids linked peptide bond. Depending on the composition, proteins differ in their properties. For example, these substances play a role building material, since every cell of the body includes them in its composition. Some types of proteins are enzymes and hormones, as well as a source of energy. They influence the development and growth of the body, regulate the acid-base and water balance.

The table of carbohydrates in food showed that in meat and fish, as well as in some types of vegetables, their number is minimal. What is the content of proteins in food? The richest product is food gelatin, it contains 87.2 g of the substance per 100 g. Next comes mustard (37.1 g) and soy (34.9 g). The ratio of proteins and carbohydrates in daily intake per 1 kg of weight should be 0.8 g and 7 g. For better absorption of the first substance, it is necessary to take food in which it takes light form. This applies to proteins that are present in dairy products and eggs. Proteins and carbohydrates do not combine well in one meal. The table on separate nutrition shows which variations are best avoided:

1. Rice with fish.
2. Potatoes and chicken.
3. Pasta and meat.
4. Sandwiches with cheese and ham.
5. Breaded fish.
6. Walnut cakes.
7. Omelet with ham.
8. Flour with berries.
9. Melon and watermelon should be eaten separately an hour before the main meal.

Match well:

1. Meat with salad.
2. Fish with vegetables or grilled.
3. Cheese and ham separately.
4. Nuts in general.
5. Omelet with vegetables.

The rules of separate nutrition are based on knowledge of the laws of biochemistry and information about the work of enzymes and food juices. For good digestion, any kind of food requires an individual set of gastric fluids, a certain amount of water, an alkaline or acidic environment, and the presence or absence of enzymes. For example, a meal rich in carbohydrates, for better digestion, requires digestive juice with alkaline enzymes that break down these organic substances. But food rich in proteins already requires acidic enzymes ... By following the simple rules of food compliance, a person strengthens his health and maintains a constant weight, without the help of diets.

"Bad" and "good" carbohydrates

"Fast" (or "wrong") substances are compounds that contain a small number of monosaccharides. Such carbohydrates are able to be quickly digested, increase blood sugar levels, and also increase the amount of insulin secreted. The latter lowers blood sugar levels by converting it into fat. The use of carbohydrates after dinner for a person who monitors his weight is the greatest danger. At this time, the body is most predisposed to an increase in fat mass. What exactly contains the wrong carbohydrates? Products listed below:

1. Confectionery.

3. Jam.

4. Sweet juices and compotes.

7. Potatoes.

8. Pasta.

9. White rice

10. Chocolate.

Basically, these are products that do not require long preparation. After such a meal, you need to move a lot, otherwise the extra weight will make itself felt.

"Proper" carbohydrates contain more than three simple monomers. They are absorbed slowly and do not cause a sharp rise in sugar. This type carbohydrates contain a large amount of fiber, which is practically not digested. In this regard, a person remains full for a long time, for the breakdown of such food, additional energy in addition, there is a natural cleansing of the body. Let's make a list of complex carbohydrates, or rather, the products in which they are found:

1. Bread with bran and whole grains.
2. Buckwheat and oatmeal.
3. Green vegetables.
4. Coarse pasta.
5. Mushrooms.
6. Peas.
7. Red beans.
8. Tomatoes.
9. Milk products.
10. Fruits.
11. Bitter chocolate.
12. Berries.
13. Lentils.

To keep yourself in good shape, you need to eat more "good" carbohydrates in foods and as few "bad" ones as possible. The latter are best taken in the first half of the day. If you need to lose weight, it is better to exclude the use of "wrong" carbohydrates, since when using them, a person receives food in a larger volume. "Correct" nutrients low-calorie, they are able to leave a feeling of satiety for a long time. This does not mean a complete rejection of "bad" carbohydrates, but only their reasonable use.