Collection of subject articles about healthy nutrition. List and describe the main functions associated with the vital activity of the body, which are provided with energy during the consumption and assimilation of nutrients. The balance of energy, which involves a

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Ministry of Education and Science of Ukraine

National Technical University

"Kharkiv Polytechnic Institute"

EDUCATIONAL - METHODOLOGICAL AID

for students of all forms of education in specialties

7.05130111 "Chemical technologies of food additives and cosmetics" ta 7.05140101 "Industrial biotechnology"

CHEMISTRYFOOD

MAIN FOOD GROUPS

FOOD DIET OF MODERN MAN

L.V. Krichkovskaya, I.V. Gritsaenko,

L.S. Mironenko, T.A. Ovsyannikova, K.V. merge

Kharkov - 2014

UDC 664.38 (075)

Reviewers:

Zhukov V.I., Doctor of Medical Sciences, Prof., Head. cafe biochemistry KSMU;

Distanov V.B., Ph.D., Assoc. cafe organic synthesis and nanotechnologies, NTU "KhPI".

KrichkovskayaL.V., Gritsaenko I.V., MironenkoL.S., Ovsyannikova T.A., Slis K.V.

Chemistry of food. Major food groups. Diet modern man. Textbook / L.V. Krichkovskaya, I.V. Gritsaenko, L.S. Mironenko, T.A. Ovsyannikova, K.V. Merged. Kharkov: NTU "KhPI", 2013. - 106 p. - Rus. lang.

The purpose of the manual is to familiarize students with modern data on the main groups of biologically active substances and food additives, their classification, hygienic regulation in food, ways of use and role in food production.

The manual is intended for students of higher educational institutions of all forms of education of specialties 7.05130111 "Chemical technologies of food additives and cosmetics" and 7.05140101 "Industrial biotechnology".

The purpose of the help is to inform students from current data about the main groups of biologically active speeches and food additives, their classification, hygienic regulation in food products, victorious ways and role in the selection of food products.

Guidelines for appointments for students of the highest initial pledges of all forms of training in specialties 7.05130111 "Chemical technologies of food additives and cosmetic products" and 7.05140101 "Industrial biotechnology".

Foreword
Section 1. Main food groups. The diet of modern man
1.1 Nutrition basics
1.1.1 Functional ingredients
1.1.2 Physiological aspects of chemistry nutrients
1.1.3 Requirements for functional ingredients
1.1.4 Functional products
Security questions for section 1
Section 2. Theories and concepts of nutrition
2.1 The history of the formation of scientific ideas about nutrition
2.1.1 The first principle of good nutrition
2.1.2 The second principle of good nutrition
2.1.3 The third principle of good nutrition
Security questions for section 2
Section 3. Recommended Dietary and Energy Intakes
3.1 The importance of a balanced diet for health
3.2 Digestion and nutrient transport
3.2.1 Human digestive enzymes
3.2.2 Main steps of digestion and absorption
3.3 Carbohydrate metabolism in the human body
3.3.1 Physiological significance of some carbohydrates
3.3.2 Technological role of carbohydrates
3.3.3 Functions of mono- and oligosaccharides in foods
3.3.4 Functions of polysaccharides in foods
3.3.5 Transformation of carbohydrates during food production and storage
3.4 Vitamins and their role in human nutrition
3.4.1 Main food groups for vitamin fortification
3.4.2 Technological importance of vitamins
3.4.3 Changing vitamins in the manufacturing process
3.5 Minerals and their role in human nutrition
3.5.1 Changes in mineral substances during the technological processing of raw materials and foodstuffs
3.6 Principles of food fortification with micronutrients
Security questions for section 3
Section 4. Food additives
4.1 Ordinal number of taste
4.2 The Mystery of the Crimson Kermes
4.3 Food of tomorrow
4.4 Classification of food additives
4.5 Black list of food additives
4.6 Truth of life
4.7 Food supplements in the prevention of premature aging
4.7.1 Water
4.7.2 Vitamins
4.7.3 Minerals
4.7.4 Amino acids
4.7.5 Connective tissue protectors
4.7.6 Phytohormones
Security questions for section 4
Bibliography
Application

Foreword

In 2004, the specialty 7.091628 "Chemical technology of food additives and cosmetics" was created by the decision of the Ministry of Science and Education of Ukraine. The uniqueness of this specialty lies in the fact that the educational material used to prepare students is at the intersection of such sciences as organic, analytical, colloidal chemistry, biochemistry, biology, technology of food products and cosmetics.

An important place in the training of specialists in the specialty "Chemical Technology of Food Additives and Cosmetics" is occupied by knowledge and understanding of the main groups of biologically active substances and food additives, their classification, hygienic regulation in food, ways of use and role in food production.

The writing of the textbook was preceded by the teaching by the authors at the Department of Organic Synthesis and Nanotechnology of the National Technical University "Kharkiv Polytechnic Institute" of the lecture and laboratory course "Technology of production of biologically active additives".

The authors hope that the manual will be useful not only for students of the specialty "Chemical Technology of Food Additives and Cosmetics", but also for students and teachers of food specialties.

Section 1. Main food groups. The diet of modern man

The diet of a modern person, which ultimately determines his health, is formed on the basis of the physiological needs for energy, macro- and micronutrients, taking into account the three principles of rational nutrition. At the same time, one way or another, it reflects the individual characteristics, economic opportunities and eating habits of a person.

In fact, today there are no strict, normatively fixed rules for compiling a diet. Perhaps the only rule is a variety of diet that provides all the physiological needs of a person. General recommendations Nutritionists include:

- consumption of various food products;

- maintenance of ideal body weight;

- reduced consumption of fats, saturated fats and cholesterol;

- increased consumption of carbohydrates (starch, fiber);

- reducing sugar consumption;

- reduction of sodium intake (NaCl).

The latest WHO food policy recommendations include the following:

a) the production of cereals and potatoes should provide more than 50% of energy intake;

b) the production of vegetables (including potatoes) and fruits should ensure their consumption at a level of at least 400g per person per day.

In general, the following four food groups should be included in the daily diet:

1) meat, fish, eggs - sources of proteins and minerals;

2) potatoes, bread, cereals and other cereal products - sources of proteins, carbohydrates;

3) milk and dairy products (including yogurts, cheeses) - sources of proteins, carbohydrates, calcium, B vitamins;

4) fruits and vegetables - sources of vitamins and minerals.

With the change in energy requirements, dietary formulation should include the need to match the level of micronutrients to physiological norms.

It has been established that with prolonged consumption of a diet with an energy value of less than 1500 kcal, the optimal supply of nutrients to the body is disturbed. Given the trend towards a further decrease in human energy needs, the diet should provide the necessary level of essential micronutrients.

1.1 Nutrition basics

The normal functioning of the human body is determined by three main factors, which include the intake of food, water and the presence of oxygen. The totality of processes associated with the consumption and assimilation in the body of the substances that make up food is called nutrition.

Nutrition includes successive processes of intake, digestion, absorption and assimilation in the body of nutrients necessary to cover its energy costs, build and renew cells and tissues of the body and regulate body functions.

Issues related to the influence of nutrients on the human body, the optimal conditions for their digestion and assimilation, the body's needs for nutrients, studies nutritional physiology.

1.1.1 Functional ingredients

All positive nutrition products contain ingredients that give them functional properties. According to D. Potter's theory, the following main types of functional ingredients are effectively used at the current stage of market development:

- dietary fiber (soluble and insoluble);

-vitamins (A, group B, D, etc.);

- minerals (calcium, iron);

- polyunsaturated fats (vegetable oils, fish oil, sch-3- and sch-6-fatty acids);

- antioxidants: β-carotene, vitamin C (ascorbic acid) and vitamin E (β-tocopherol);

- oligosaccharides (as a substrate for beneficial bacteria), trace elements, bifidobacteria, etc.

Functional Properties dietary fiber mainly related to work gastrointestinal tract. Food rich in fiber has a positive effect on the digestive process and therefore reduces the risk of diseases associated with these processes, such as colon cancer. The development of cancer is a complex process with numerous factors. Dietary fiber increases the volume of feces by diluting their contents. This leads to a decrease in the interaction of carcinogenic metabolic products with the intestinal mucosa. Soluble and insoluble fibers increase the feeling of satiety, because. fiber-enriched foods take longer to chew and digest, thereby causing more saliva and gastric juice. Satisfying the feeling of hunger prevents the excess food intake associated with obesity. Soluble fibers, especially pectin, have been found to have a positive effect on cholesterol metabolism in the body. One possible explanation for the cholesterol-lowering effect is that soluble fibers promote the extraction of bile acids and increase their excretion from the body.

Fibers are of great practical importance in the prevention of diseases such as diabetes mellitus. The consumption of fatty and sugary foods, which is typical of our society, leads to weight gain, anticipating the development of diabetes. Eating foods containing fiber has a positive effect on the condition of the teeth and oral cavity. A longer process of chewing such food helps to remove bacterial plaque that is present on the teeth. High-fiber foods contain less sugar than foods rich in carbohydrates and fats, which also helps to reduce the risk of cavities.

Vitamins and Antioxidants, which include vitamins A, C, E, vitamins of group B and provitamin A - β-carotene, being functional ingredients, play an important role in positive nutrition. They are involved in metabolism, strengthen the body's immune system, and help prevent diseases such as scurvy and beriberi.

Antioxidants include beta-carotene and vitamins C and E. Antioxidants slow down the oxidation of unsaturated fatty acids that make up lipids by interacting with oxygen, and also destroy already formed peroxides. Antioxidants protect the human body from free radicals, exhibiting an anticarcinogenic effect, and also block active peroxide radicals, slowing down the aging process.

Minerals as functional ingredients have the following properties:

- sodium stabilizes the osmotic pressure of the intercellular fluid, improves muscle function;

- potassium plays an important role in cell metabolism, promotes neuromuscular activity.

1.1.2 Physiological aspects of food chemistry

In general, the chemical composition of a food product is formed by three main groups of components:

a) food raw materials,

b) nutritional supplements,

c) biologically active additives.

Food raw materials- objects of plant, animal, microbiological, as well as mineral origin used for the manufacture of food products.

Nutritional supplements- natural or synthesized substances, compounds specially introduced into food products in the process of manufacturing the latter in order to impart certain (given) properties to food products and (or) preserve their quality.

Biologically active additives- concentrates of natural (identical to natural) biologically active substances intended for direct intake with food or introduction into food products.

Name food received food chemicals that are assimilated in the body's metabolic process. In the aspect of nutritional biochemistry, all substances that can be found in the composition of a food product are generally divided into three main classes: two classes of actually food (alimentary: from English - food, nutrient) substances - macro- and micronutrients and a class of non-food (non-alimentary) substances. Representatives of each of the classes differ in chemical composition, features of physiological action and the level of content in food products. The modified classifier of the main food substances proposed by A.A. Pokrovsky, includes the following groups:

Macronutrients(from the Latin "nutrition" - nutrition) - a class of main nutrients, which are sources of energy and plastic (structural) materials; are present in food in relatively large quantities (from 1 g). Representatives of this class are carbohydrates, lipids and proteins.

Micronutrients- a class of nutrients that have pronounced biological effects on various functions of the body; found in food, usually in small amounts (milli- and micrograms).

The class of micronutrients includes vitamins, vitamin precursors and vitamin-like substances, as well as minerals. In addition to these biologically active food components, the class of micronutrients (according to A. Pokrovsky) includes some food substances isolated from separate groups of macronutrients. These include: representatives of the lipid group (polyunsaturated fatty acids and phospholipids); representatives of proteins (some amino acids); representatives of carbohydrates (individual oligosaccharides).

AT third class isolated substances that are usually contained in food products, but not used by the body in the process of life. To such substances, combined by the term " non-food", belong to various technological additives (flavors, dyes, preservatives, antioxidants, etc.), toxic substances, etc.

However, the role of many non-alimentary substances is currently being re-examined. The reason for this was the discovery of new properties in individual non-food substances related to the physiology of nutrition. These include (representing the group of ballast substances) dietary fiber, precursors for the synthesis of biologically active substances, enzymes and eubiotics (synonymous with the term "probiotics"). The latter are, in accordance with the latest edition of this term, nutritional supplements of microbial origin that have a positive effect on the human body through the regulation of intestinal microflora. All natural biologically active food ingredients of classes II and III, which have a pronounced effect on many functions of the body, are combined by the term " nutraceuticals". From the class of micronutrients to special group, united by the name " parapharmaceutics", release food substances that have a pronounced pharmacological effect. The group of parapharmaceuticals includes bioflavonoids, glycosides, alkaloids, essential oils, organic acids and many others. Each group of nutrients in the processes of nutrition has its own special role.

Squirrels, coming from food, perform three main functions:

1) they are a source of 10 essential and 10 non-essential amino acids, which are used as building blocks during protein biosynthesis not only in children (including newborns), but also in adults, ensuring the constant renewal of proteins and their circulation;

2) amino acids serve as precursors for hormones, porphyrins, and many other biomolecules;

3) oxidation of the carbon skeleton of amino acids makes a small but important contribution to the daily total expenditure of activity, regulates intracellular osmotic pressure, improves muscle performance;

trace elements

- magnesium activates the activity of enzymes and neuromuscular activity, reduces the risk of atherosclerosis;

- calcium contributes to the work of cell membranes, enzymatic activity, participates in the structure of bone tissue;

- phosphorus is involved in the structure of bone tissue, promotes the functioning of nerve cells, the work of enzymes and cell metabolism;

- zinc contributes to the growth of the body, participates in the work of metalloenzymes;

- selenium activates the immune system, is a detoxifier, participates in the control of free radicals;

- iodine regulates the amount of thyroid hormones (anti-goiter);

- iron is involved in hematopoiesis, carries oxygen.

Polyunsaturated fatty acids have been especially intensively studied by scientists over the past 20 years. It has been established that the most effective functional ingredients of this group are unsaturated fatty acids with the location of the first double bond, counting from the CH 3 group, between the third and fourth carbon atoms - omega-3 fatty acids. These acids include linolenic, eicosapentaenoic and docosahexaenoic acids. Unsaturated fatty acids are involved in the breakdown of low-density lipoproteins, cholesterol, prevent the aggregation of blood cells and the formation of blood clots, relieve inflammatory processes etc.

bifidobacteria belong to the functional ingredients of the complex effect. The system "human body - intestinal microflora" is capable of self-regulation. However, it is currently known big number factors exceeding the compensatory capabilities of the microecological system. These include pharmacological preparations, industrial poisons, pesticides, radiation, stress conditions, etc. An imbalance in human microbial ecology leads to serious illnesses both the gastrointestinal tract and the body as a whole. Bifidobacteria help to restore and maintain the normal microflora of the body, have a multifactorial regulatory and stimulating effect, they are a source of essential amino acids for the body, including tryptophan, and lower blood cholesterol levels. To the most important properties bifidobacteria include their anticarcinogenic and antimutagenic activity.

Plant and milk oligosaccharides are one of the main sources of carbohydrates in human nutrition. Their functional significance lies in the fact that they serve as a substrate for bifidobacteria. Highly effective bifidogenic factors are oligosaccharides from honey syrup, cotton seeds and various grains.

1.1.3 Requirements for functional ingredients

Ingredients that give products functional properties must meet the following requirements:

- be useful for nutrition and health (useful qualities must be scientifically substantiated, and daily doses must be approved by experts);

- be safe in terms of balanced nutrition;

- have accurate physical and chemical parameters and precise methods for their determination;

- do not reduce the nutritional value of food products;

- taken orally (as regular food);

- have the appearance of ordinary food (not produced in such dosage forms like tablets, capsules, powders);

- be natural.

1.1.4 Functional products

There are currently four product groups functional nutrition: breakfast cereals, dairy products, fat emulsion products and vegetable oils, soft drinks. The content of functional ingredients in these products is shown in the table.

Security questions for section 1

1. List the food groups that should be included in the daily diet.

2. What does nutritional physiology study?

3. List the main types of functional ingredients.

4. Describe the functional properties of dietary fiber.

5. Describe the groups of food product components.

6. Define micro and macro nutrients, give examples.

7. Explain why bifidobacteria belong to the functional ingredients of the complex effect?

8. What are the requirements for functional ingredients?

9. List and describe functional food groups?

Section 2. Theories and concepts of nutrition

2.1 The history of the formation of scientific ideas about nutrition

The formation of scientific ideas about nutrition and the role of nutrients in life processes began only in the middle of the 19th century with the advent of the classical nutrition paradigm, which was preceded by a number of scientific discoveries directly or indirectly related to nutrition. These include the discovery of vitamins, microelement ions, scientific achievements related to the elucidation of the structure of proteins, fats, carbohydrates and nucleic acids, the role of trace elements in the life of the body, the structure and organization of biological systems, scientific data related to the structure of the body at the cellular level.

For the first time in the history of evolution, the goal of nutrition began to be associated with human health.

The essence of the first scientific paradigm of nutrition was reduced to the need to provide the body with nutrients that are required for its normal functioning and release from ballast components.

The concentrated expression of the classical paradigm was finally formed in late XIX- early XX century, theory of balanced nutrition based on three main principles:

1. With ideal nutrition, the influx of substances exactly corresponds to their loss.

2. The influx of nutrients is provided by the destruction of food structures and the use of the resulting organic and inorganic substances by the body.

3. The body's energy expenditure must be balanced with energy intake.

According to this theory, the normal functioning of the body is ensured when it is supplied not only with the necessary energy and protein, but also when certain ratios are observed between numerous irreplaceable nutritional factors, each of which performs its specific function in metabolism.

The concept of a balanced diet is based on the determination of the proportions of individual nutrients in the diet, reflecting the sum of metabolic reactions that characterize the chemical processes that ultimately ensure the vital activity of the organism.

One of the main biological laws on which the theory is based is the rule of correspondence between the body's enzyme sets and the chemical structures of food. The formula for a balanced diet according to A. Pokrovsky is a table that includes a list of food components with the needs for them in accordance with physiological characteristics organism. The formula is based on the total energy value of the daily norm of nutrients equal to 3000 kcal. In accordance with the trends towards a decrease in the energy needs of a modern person, the norms for the consumption of macronutrients (energy sources) are also being revised.

Based on the formula for a balanced diet, a complete diet should contain five classes of nutrients:

- sources of energy - proteins, fats, carbohydrates;

- essential amino acids;

- vitamins;

- essential fatty acids;

- inorganic elements.

Water, although it is not a nutrient in the literal sense of the word, it is also necessary for a person to reproduce losses in various processes, for example, during breathing, sweating, etc. Typically, the body uses 300-400 ml of metabolic (endogenous) water released during the process of biological oxidation; the rest of the amount that provides the daily requirement (1750-2200 g) must be supplied to the body with liquid food.

Thus, a balanced diet is associated with taking into account all nutritional factors, their relationship in metabolic processes, as well as the correspondence of enzymatic systems to chemical transformations in the body. But the balanced approach to nutrition led to the erroneous conclusion that only the components of food absorbed by the body are valuable, while the rest, the substances, are ballast. The ill-advised conclusion was made that improving the quality of food is associated with the removal of dietary fiber and its enrichment with nutrients (nutrients). However, the generalization of subsequent experience related to the creation and consumption of such food, as well as the study of the role of ballast substances and intestinal microflora in energy processes, showed the need for the presence of ballast substances in food.

The daily requirement for proteins is 85-90 g. An indicator of the quality of a food protein, which reflects the degree to which its amino acid composition corresponds to the body's needs for amino acids for protein synthesis, was called biological value.

For normal nutrition essential amino acids should be 36-40%, which is ensured at a ratio of vegetable proteins to animals equal to 45: 55%.

vitamins are essential components of specific coenzymes or enzymes involved in metabolism and other specialized reactions. They are organic micronutrients, the daily requirement for which does not exceed a few milligrams and even micrograms. In accordance with the latest WHO recommendations, it should be satisfied primarily through the consumption of natural products.

Inorganic substances and trace elements necessary for normal nutrition. They can be divided into two groups:

- a) macronutrients, i.e. those required in gram amounts (calcium, phosphorus, magnesium);

- b) trace elements, the need for which does not exceed milligrams or even micrograms (iron, iodine, zinc, copper and others).

Inorganic substances perform various functions. They are structural components of bones and teeth, electrolytes in maintaining the water-salt balance of blood and tissues, as well as prosthetic groups of enzymes. The optimal ratio of the main macroelements - calcium, phosphorus and magnesium - should be 1:1.3:0.5.

2.1.1 The first principle of good nutrition

food for human body is primarily a source of energy. It is during its transformations - oxidation and decomposition of complex substances into simpler ones - that the energy necessary for the body in the processes of vital activity is released. (Energy is expressed in kilocalories (kcal) or kilojoules (kJ), 1 kcal corresponds to 4.18 kJ.)

The role of the main sources of energy belongs to macronutrients - proteins, fats and carbohydrates. The share of energy that can be released from macronutrients during biological oxidation characterizes the energy value (calorie content) of the product.

According to the energy value (calorie content), food products are divided into 4 groups:

1. Especially high-energy: chocolate, fats, halva 400-900;

2. High-energy: flour, cereals, pasta, sugar 250-400;

3. Medium energy: bread, meat, sausage, eggs, egg liquor, vodka 100-250;

4. Low energy: milk, fish, potatoes, vegetables, fruits, beer, white wine up to 100.

The energy value is one of the main properties of a food product that determines its nutritional value.

Nutritional value of the product- a set of properties of a food product, in the presence of which the physiological needs of a person in the necessary substances and energy are satisfied. The energy provided by the body during the consumption and assimilation of nutrients is spent on the implementation of three main functions associated with the vital activity of the body. These include: basal metabolism, digestion of food, muscle activity.

BX- this is the minimum amount of energy needed by a person to maintain life in a state of complete rest (during sleep in comfortable conditions). The energy needed by a person to ensure basal metabolism depends on age, gender, external conditions, etc. It is believed that in 1 hour a middle-aged person spends 1 kcal per 1 kg of body weight. In children, this consumption is 1.3 - 1.5 times higher. For a man aged 30 years with an average weight of 65 kg (conditionally accepted as a standard), it is 1570 kcal, for a woman (30 years old, 55 kg) - 1120 kcal.

Digestion of food, associated with its specific dynamic action in the absence of muscle activity, also requires energy. It has been established that the intake of food into the digestive tract for a certain period increases the energy characteristic of the basal metabolism. The highest energy expenditure is required for the digestion of protein foods, the smallest for the digestion of carbohydrates. It is believed that with the optimal amount of substances consumed under conditions of mixed nutrition, the increase in basal metabolism due to the specific dynamic action of food is on average 10-15%, which corresponds to 140-160 kcal per day.

muscle activity, determined by the activity of a person's lifestyle, requires different energy, which depends on the type of physical activity and is directly related to the nature of the work. Even the simplest, lightest movements increase energy expenditure over and above basal metabolism. On average, muscle activity requires 1000-2500 kcal daily. An objective physiological criterion that determines the amount of energy adequate to the nature of the activity is the ratio of total energy consumption for all types of life activity with the value of the basal metabolism, which is called the coefficient of physical activity (CFA). So, to ensure the normal functioning of a person, it is necessary to create conditions for a relative balance between the energy that a person spends and the energy that he receives with food. Energy balance means the ratio between the energy consumed and consumed. In the case of a positive energy balance, which will be maintained for a certain period of time, excess energy will be accumulated as fat in adipose tissue, which can eventually lead to overweight and then to obesity.

2.1.2 The second principle of good nutrition

In accordance with the second principle of rational nutrition, the body's need for basic nutrients, including energy sources (proteins, fats, carbohydrates), essential amino acids, essential higher fatty acids, vitamins, and minerals, must be satisfied. That is, a complete diet should include five classes of nutrients, each of which performs its specific functions in the body. In general, the physiological significance of the main groups of nutrients can be represented as follows.

Carbohydrates are the most common nutrients: as a result of the oxidation of carbohydrates in the human body, the main part of the energy is produced. The coefficient of energy value is 4 kcal / g. In addition, they serve as precursors in the biosynthesis of many cell components. Carbohydrates by themselves are not essential nutrients in the human diet. However, foods rich in carbohydrates are more readily available and cheaper than foods containing a large number of proteins and fats, which is why they make up the bulk of food in most countries. Four-fifths of the world's population eats mainly plant foods, in which carbohydrates account for 70, and sometimes 90% of total calories. AT developed countries, where the population consumes meat and dairy products in relatively large quantities, carbohydrates account for only 45% of the daily caloric intake.

In accordance with the basics of rational nutrition, the daily requirement of the human body for carbohydrates is 400-500 g, which corresponds to 53-58% of the daily caloric intake. At the same time, sugar should account for only 10-20%, i.e. 50-100 g. A large amount of sucrose and other low molecular weight sugars has adverse effect on the teeth. The main share of carbohydrate food is starch. The class of carbohydrates also includes dietary fiber, the daily requirement for which reaches 25 g (including pectin substances 5-6 g).

Fats or triacylglycerols- animal products and plant origin. Like carbohydrates, they are one of the main sources of energy (the energy value coefficient is 9 kcal / g), and in addition they serve as a source of carbon atoms in the biosynthesis of cholesterol and other steroids. Triacylglycerols of plant origin are also a source of essential fatty acids. An indicator of the quality of fatty components, reflecting the content of polyunsaturated fatty acids in them, is called biological efficiency. Unlike carbohydrates, fats are usually retained and digested in the stomach more slowly, and therefore they are better than carbohydrates in promoting satiety. According to the latest data, the body's daily need for fats is 60-80 g, which corresponds to 30-35% of the total energy value of the diet. The optimal ratio of vegetable and animal fats corresponds to 7: 3. This ratio provides for the utilization of fats in the process of digestion, the supply of various types of higher fatty acids in the following proportions: 30% - saturated, 60% - monounsaturated, 10% - polyunsaturated, which is considered optimal from the standpoint of rational nutrition.

Physiologically valuable components of the lipid nature are phospholipids contained in vegetable fats, which are necessary for the renewal of cells and intracellular structures. The daily requirement of the body for phospholipids in accordance with the formula of A. Pokrovsky is 5 g.

2.1.3 The third principle of good nutrition

According to the third principle of rational nutrition, the main thing for the normal functioning of the body is not only what kind of food and how much a person consumes, but also how and when this consumption occurs.

The third principle of rational nutrition is based on four basic rules:

- regularity of nutrition, which takes into account a complex of factors that ensure normal digestion;

- fragmentation of food during the day, which should be at least 3-4 times a day;

- rational selection of products at each reception;

- the optimal distribution of food during the day, in which dinner should not exceed one third of the daily diet.

The regularity of nutrition is associated with the observance of the meal time, at which a person develops a reflex of secretion of digestive juice, which ensures normal digestion and assimilation of food.

The rational distribution of food during the day (fractionation of nutrition) according to the amount of food consumed and its energy value ensures an even load on the digestive apparatus and creates conditions for the timely provision of the body with the necessary energy and nutrients. The formation of a selection of products at each reception should ensure optimal conditions for digestion of food. Products containing animal proteins are more rational to consume in the first half of the day, and dairy and vegetable foods in the second.

The optimal distribution of food during the day is differentiated depending on age, the nature of physical activity, and the daily routine. For middle-aged people, the most rational is four meals a day, for the elderly - five meals a day with intervals between meals of 4-5 hours. less rational is Three meals a day, which increases the amount of food consumed and the load on the digestive apparatus. Official statistics show a trend towards an increase in the number of meals during the day. These trends are especially pronounced in developed countries and are due to changes in the lifestyle of a modern person. For the French, for example, the number of daily meals has increased today to 6, and for some Americans - up to 20.

Grain-based products are healthy due to their content of soluble and insoluble dietary fiber, which, by reducing cholesterol levels, helps reduce the risk of cardiovascular disease, and also stabilizes the digestive functions of the body, preventing diseases of the gastrointestinal tract.

Dairy products are a valuable source of functional ingredients such as calcium and riboflavin. Their functional properties can be enhanced by adding vitamins A, B, E, β-carotene and minerals (magnesium), as well as dietary fiber (pectin) and bifidobacteria. Functional dairy products can be effective in preventing cardiovascular disease, gastrointestinal disease, osteoporosis, cancer, and other diseases.

Vegetable oils, non-hydrogenated vegetable fat-based oils, emulsifiable fat-and-oil products of various types are the main sources of polyunsaturated fatty acids. They help prevent cardiovascular disease. To enhance the functional effect, ingredients such as vitamin D, some triacylglycerols can be introduced into their composition. These products, while reducing the mass fraction of fat in their composition, are also effective in preventing obesity.

Drinks are the most technologically advanced product for creating new types of functional nutrition, since the introduction of new functional ingredients into them is not very difficult. Drinks enriched with vitamins, microelements, dietary fiber can be used to prevent cardiovascular and gastrointestinal diseases, cancer and other diseases, as well as various types of intoxication.

In the 80s. 20th century A new theory of nutrition was formulated, which is a development of the theory of balanced nutrition, taking into account the latest knowledge about the functions of dietary fiber and intestinal microflora in nutritional physiology. This theory, the author of which was the Russian physiologist Academician A.M. Ugolev, was named theory of adequate nutrition .

The theory is based four fundamental provisions:

- food is digested both by the organism that absorbs it and by the bacteria inhabiting it;

- the influx of nutrients in the body is ensured by extracting them from food and as a result of the activity of bacteria that synthesize additional nutrients;

- normal nutrition is determined not by one, but by several flows of nutrients and regulatory substances;

- physiologically important components of food are ballast substances, called "dietary fibers".

under the term " alimentary fiber"combine the biopolymer components of plant foods, which include indigestible polysaccharides, including cellulose, hemicedulose, pectins (native protopectins) and polyphenolic compounds - lignins. Celluloses and hemicelluloses are practically insoluble components, while pectins and lignins are soluble polymers These components, which form the structural basis of the cell walls and membranes of fruits, are largely removed during the technological processing of plant materials into food products.Examples include the technology of processing grain into flour, grinding rice, squeezing juice from fruits, and various extraction processes.In accordance with the theory of balanced nutrition, these components were considered ballast substances and their removal from food during technological processes was recognized as necessary, which ultimately led to a significant reduction in their content in the traditional diet and, as a result, negatively seemed to be on public health.

The specific physiological properties of dietary fiber include: stimulation of intestinal peristalsis; adsorption of various toxic products, incl. products of incomplete digestion, radionuclides, some carcinogens; intensification of the metabolism of bile acids, which regulates the level of cholesterol in the blood;

a decrease in the availability of macronutrients (fats and carbohydrates) to the action of digestive enzymes, preventing a sharp increase in their content in the blood; accessibility to the action of intestinal microflora (as a permanent nutrient substrate), the activity of which ensures the intake of valuable secondary nutrients (B vitamins and others) into the body and manifests itself in various other positive effects on metabolism. The functions of soluble and insoluble dietary fibers differ: celluloses and hemicelluloses mainly act as peristalsis stimulants, while pectins are sorbents and nutrient substrates for intestinal microflora.

The theory of adequate nutrition formulates the basic principles that ensure rational nutrition, which takes into account the whole complex of nutritional factors, the relationship of these factors in metabolic processes and the correspondence of the body's enzyme systems individual characteristics chemical transformations taking place in it.

basis rational nutrition are three main principles.

1. The balance of energy, which implies the adequacy of the energy supplied with food, and the energy expended in the processes of vital activity.

2. Satisfying the needs of the body in the optimal amount and ratio of nutrients.

3. A diet that involves observing a certain time and number of meals, as well as a rational distribution of food at each meal.

Security questions for section 2

1. What are the main provisions of the theory of balanced nutrition?

2. Describe the main sources of energy. How are foods classified according to energy value?

3. What is the nutritional value of the product, how does it differ from the energy value?

4. List and describe the main functions associated with the vital activity of the body, which are provided with energy during the consumption and assimilation of nutrients.

5. What is the essence of the second principle of rational nutrition?

6. What rules underlie the third principle of rational nutrition?:

7. What is the theory of adequate nutrition, what fundamental provisions underlie it?

8. Define "dietary fibers", characterize their physiological properties.

Section 3. Recommended Dietary and Energy Intakes

3.1 The importance of a balanced diet for health

A varied and balanced diet does not create nutritional safety problems, mainly associated with certain deficiency or excess of individual nutrients or their combinations. Nutrient imbalances rank second (after microbial contamination) among the most important potential sources of harm in foods. Today, prolonged malnutrition is seen as a risk factor for the most common adult diseases in our civilization. These diseases, the occurrence and development of which are associated with malnutrition, include;

- cancer diseases(cancer of the gastrointestinal tract and breast), whose nutritional risk factors are increased consumption of fats and salt, as well as the presence of carcinogenic additives in products (nitrates, nitrosamines, benzopyrenes, etc.);

-cardiovascular diseases, which are associated with high blood cholesterol levels;

- violation of the functions of the gastrointestinal tract, due to abnormalities in the functions of the intestinal microflora, low content of dietary fiber in foods;

- osteoporosis - a change in the composition of bones in old age, associated with the loss of calcium;

- obesity, due to increased consumption of fats, alcohol against the background of low physical activity.

The main health strategy that is recommended to address this problem is the development of national norms for nutrient and energy intake, taking into account nutritional status, living standards and other national and state features specific country. In Russia, such norms were developed by the Institute of Nutrition of the Russian Academy of Medical Sciences and approved by the Chief State Sanitary Doctor. The norms of physiological needs for the adult population are differentiated depending on gender, age and coefficient of physical activity.

Along with diseases caused by an imbalance of essential nutrients, even in the developed countries of Europe, deficiency diseases still persist due to a deficiency in food of certain micronutrients. These include iodine, iron, folate, vitamins. One of the main reasons for the increased risk of micronutrient deficiencies is the trend towards lower energy requirements due to reduced levels of physical activity. As a result, in order to maintain body weight and prevent obesity, a person tends to eat less, changes the existing diet, which leads to a lack of micronutrients. To ensure health, the content of minerals and vitamins in the diet must be maintained at a level corresponding to the physiological needs of a person. Techniques for maintaining adequate micronutrient intake include:

- enrichment with nutrients of traditional foods (for example, fortification);

- consumption of multivitamin and vitamin-mineral complexes with food.

According to the latest WHO recommendations, under normal conditions, the most effective strategy for primary prevention is associated with an increase in consumption of food sources of micronutrients - vegetables and fruits - against the background of increased physical activity.

3.2 Digestion and nutrient transport

Digestion is a complex process in which food in the digestive tract undergoes physical and chemical changes that allow nutrients to be absorbed into the bloodstream.

Physical food changes are in its grinding, mixing, swelling, partial dissolution, formation of suspensions and emulsions.

Chemical changes are associated with a number of successive stages of splitting of the main nutrients (proteins, fats, carbohydrates).

3.2.1 Human digestive enzymes

The process of destruction of natural polymers is carried out in the body by enzymatic hydrolysis with the help of digestive enzymes - hydrolases. Only macronutrients are depolymerized. Three groups of hydrolases are involved in this process: proteases - are involved in protein hydrolysis, lipases - in fat hydrolysis, amylases - break down carbohydrates. Enzymes are formed in special secretory cells of the digestive glands and enter the digestive tract along with saliva, gastric, pancreatic and intestinal juice.

human digestive tract includes: mouth, pharynx, esophagus, stomach, duodenum (upper part of the small intestine), small and large intestines. Moving through the digestive tract, food substances are successively exposed to the action of various enzymes and ultimately, mainly, are broken down to a minimum size. The process of digestion can be carried out in three ways: the main one is extracellular (cavity) digestion, which occurs mainly in the digestive tract. Together with it, intracellular and parietal (membrane) digestion takes place in the body, which occurs on the inner surface of the small intestine.

3.2.2 Main steps of digestion and absorption

1. In the oral cavity the main process of food processing are mechanical (grinding) and colloidal (wetting with saliva and swelling) processes. As a result of these processes, a food bolus is formed from food. In addition to these processes, chemical processes also begin here. Human saliva (pH of saliva is close to neutral) contains enzymes that break down carbohydrates. But in the oral cavity, starch is not broken down to glucose, because. food is here for a short time, so mucus is formed, consisting of maltose, glucose, oligosaccharides. The duration of food processing in the oral cavity is 15 - 18 seconds. The food bolus from the root of the tongue through the pharynx and esophagus enters the stomach.

2. in the stomach digestion continues for 6 to 12 hours.

Colloidal (wetting, swelling), physicochemical (penetration of gastric juice into the food bolus, coagulation of proteins, curdling of milk, etc.) and chemical processes take place here, in which the enzymes of gastric juice participate.

Pure gastric juice is a colorless transparent liquid containing hydrochloric acid at a concentration of 0.4 - 0.5% (pH 1.5 - 2.5). Hydrochloric acid creates an environment that activates acid proteases (pepsin and gastrixin) and promotes denaturation and swelling of proteins, which facilitates their hydrolysis.

Three groups of enzymes work in the stomach:

- saliva enzymes - amylases, which act for the first 30 - 40 seconds before the appearance of an acidic environment;

- enzymes of gastric juice - proteases (pepsin, gastrixin, gelatinase).

They break down proteins to polypeptides and gelatin and lipase, break down fats. Since lipases usually act only on emulsified fats in a slightly alkaline environment, the duration and activity of their action is short. The products of fat depolymerization are acylglycerols.

3. In the intestines the contents of the stomach pass after the consistency of the food becomes liquid or semi-liquid. The upper part of the small intestine is called the duodenum. In it, food is exposed to the action of pancreatic juice, which contains a complex of enzymes and bicarbonates, creating a slightly alkaline environment (pH 7.8 - 8.2). In addition, bile and intestinal juice, located in the intestinal mucosa, act on food.

a) As pancreatic juice enters the duodenum, hydrochloric acid is neutralized and the pH value increases. In humans, the pH of the environment in the duodenum ranges from 4.0 to 8.5. Pancreatic juice enzymes work here: proteases (trypsin, chymotrypsin, aminopeptidases, carboxypeptidases), lipases emulsified with bile acids, amylases, as well as ribonuclease and deoxyribonuclease, which cleave RNA and DNA.

...

Bakery products, cereals, legumes, potatoes

Products of this group are considered the main source of complex carbohydrates (), dietary fiber (fiber), minerals. Let's dwell on some of them.

Bread

Recently, the idea of bread as a heavy and unhealthy food is a thing of the past. Modern nutritionists recognize the benefits of this product and recommend eating an average of five slices of bread with a high content of dietary fiber per day (varieties with bran, cereal, whole grain, scalded yeast-free bread). This change in opinion about bread is based on careful study and higher appreciation nutritional value starch and. Today it is considered that bakery products in moderation are the right foods from the point of view of medicine and nutrition and an important part of our diet.

The high fiber content of bran or whole grain breads can help prevent gastrointestinal, pancreatic, and gallbladder dysfunction and possibly prevent some types of cancer. The complex carbohydrates found in bread lower blood cholesterol levels and help fight diabetes. In addition to iron and B vitamins, bread contains a number of minerals - potassium, calcium, magnesium, sodium, phosphorus. This product is an important supplier of carbohydrates and vegetable protein. The widespread belief that bread contributes to weight gain is not true: in fact, the reason is not in the bread, but in the fact that it is spread on it!

Rice

It should also be noted the widespread use of potatoes in traditional medicine in the treatment of diseases of the gastrointestinal tract and respiratory organs, diseases of the cardiovascular system, kidneys, etc. In addition, potatoes are classified as alkaline foods that prevent a decrease in blood pH.

Vegetables, fruits, berries, leafy greens

Vegetables are highly valued by doctors and nutritionists for their high content of fiber, vitamins, minerals and biologically active substances. Scientists have found a strong link between good health and a vegetable-rich diet. It has been proven that population groups that consume these foods in large quantities are less likely to get cancer, diabetes, and diseases of the gastrointestinal tract. According to experts, the benefits of vegetables and fruits are largely due to the presence in their composition of special elements - phytoprotectors ("phyto" in Greek - "plant").

With an ordinary mixed food, a person receives about 1.5 g of these valuable substances per day, and they are represented by more than 10 thousand different compounds (indoles, flavonoids, saponins, polyphenols, terpenes, etc.).

Phyto compounds are found in all vegetables and fruits. For example, in vegetables belonging to the cruciferous class (all types of cabbage, turnips, zucchini, squash, pumpkin), indole compounds were found. They have an antioxidant effect, regulate the activity of enzymes responsible for the destruction of various poisons in the body.

As recommended by the World Health Organization, various fruits and berries should be included in the diet daily even several times during the day. It can be an apple or an orange, a cup of berries - raspberries or strawberries, or a glass of juice. The menu can also include dried, frozen or canned fruits, but keep in mind that compotes, jams, syrups, jellies contain too much sugar and lose their vitamin C content. If possible, you should give preference to frozen or canned fruits. own juice, no added sugar. Fruits and berries are a valuable source of vitamin C and bioflavonoids.

The proven benefits of vegetables and fruits are also explained by their high content of soluble and insoluble fiber, which improves intestinal motility, reduces the risk of rectal cancer, and helps to reduce.

Fresh fruits and berries are low in calories, so they are an excellent food for anyone who does not want to be overweight. Most nutritionists believe that the health benefits of fruits and vegetables far outweigh the health risks of the pesticides they contain.

The concentration of the latter is regulated at levels that do not pose a danger to the health of consumers, even children. However, the risk still exists. Remember that citrus fruits are treated with a fungicide to prevent mold, since people are not supposed to eat the peel. Therefore, when preparing marmalade or candied fruits, additional precautions should be taken, which include thorough washing in running water and prolonged soaking in changing water. Be careful with fruits that are moldy or have dark spots: they can contain toxic and carcinogens produced by mold microfungi. It is better to refuse such products.

The number of vegetables and fruits in the daily diet is not limited. However, nutritionists believe that the total rate of their consumption per day should be at least 400 g (net weight), not counting potatoes (3-4 medium-sized potatoes per day are recommended).

At the same time, 1/3 of this amount should be eaten raw. Fruits and berries are recommended to be consumed at least 2 times a day: 1 apple or 1 pear, or 1/2 orange, or 3-4 plums, or 1 peach, or 2 apricots, or 1/2 glasses of berries.

Vegetables can be used both raw and for cooking side dishes and independent dishes. They should not be subjected to strong frying (at the same time a large amount of fat is absorbed), it is better to stew or bake. To improve the functioning of the body systems responsible for the destruction and elimination of various poisons, it is recommended to use cruciferous vegetables more often in the diet: all types of cabbage, especially Brussels sprouts, zucchini, squash, pumpkin. These vegetables are able to increase the rate of destruction of poisons entering the body hundreds of times and thus significantly, many times reduce the risk of them. negative impact on health.

Milk and dairy products

Milk is one of the most complete foods. Academician I.P. Pavlov called it food "which is prepared by nature itself, is distinguished by its easy digestibility and nutritional value." Milk and milk products are the right products food with high biological value. Among the most useful components of milk, first of all, easily digestible milk protein should be attributed, containing all the amino acids necessary for a person in an almost ideal ratio (there is a slight lack of sulfur-containing amino acids: methionine and cysteine).

The main representative of dairy proteins is casein (about 80% of proteins), which, forming a single complex with another important component of milk, calcium, contributes to its high bioavailability. An important role is played by the main milk carbohydrate - lactose, vitamin D, as well as the optimal content of phosphorus in milk. It should be noted a significant amount of vitamin B2 in the product, which is necessary for the prevention of a number of diseases (angular stomatitis, cheilosis, seborrheic dermatitis, etc.), as well as vitamin B12, the lack of which leads to severe hematopoietic disorders, disorders of the nervous and digestive system.

Dairy products are the right food products in their composition, useful for people of all ages, so they should occupy one of the leading positions in the diet. Nutritionists recommend consuming dairy products in an amount corresponding to about 1 liter (500 ml - of milk itself. It is imperative to include dairy products in the diet of children, pregnant and lactating women, the sick and the elderly.

Dairy products are recommended to be consumed 2 times a day. At the same time, at one time you should drink 1 glass of milk, or kefir, or curdled milk, or yogurt, or 60-80 g (4-5 tablespoons) of cottage cheese, or feta cheese, or 50-60 g of hard or processed cheese.

Meat, poultry, fish, eggs

Extractives found in meat, give it a characteristic aroma, excite the activity of the digestive glands. Strong meat broths are useful for those suffering from lack of appetite, chronic gastritis with reduced secretion of gastric juice, anemia, and exhaustion.

When meat is cooked, extractive substances pass into the broth. If chemical sparing of the gastric mucosa is necessary during exacerbation chronic gastritis with high acidity, peptic ulcer of the stomach and duodenum, chronic pancreatitis, etc., strong broths should be abandoned, and weak ones (half with boiled water) or so-called secondary broths should be used. Extractive substances also include purines, with excessive intake of which metabolic disorders, deposition of uric acid salts, exacerbation of gout are possible. To reduce the intake of purines, you should abandon fried and stewed meat and rich meat broths.

Chicken meat is widely used in the diet of most people. Allocate the meat of young (chickens, broiler chickens) and adult (hens) birds. Chicken meat contains slightly more protein than the meat of slaughtered animals (beef, lamb, pork), and less fat and saturated fatty acids. It should be noted, however, that according to a number of estimates, the biological digestibility and efficiency of chicken meat protein is somewhat inferior to those of meat from slaughter animals. One of the most dietary is the meat of chickens of the 2nd grade (they differ from the birds of the 1st grade, as a rule, in less fatness).

The composition of chicken (especially the 1st grade) includes fats and cholesterol. 60 g of boiled chicken contains about 14% of the normal daily intake of cholesterol, 12% - total fat and 9% - saturated fatty acids.

Eggs are among the foods with high nutritional value. Egg white contains all the amino acids necessary for a person in the optimal ratio, which contributes to their most complete use by the body. Along with this, eggs contain a significant amount of phospholipids (lecithin), which normalize fat metabolism in the body, as well as vitamins A and B2.

Selected chicken egg weighing 70 g contains about 20% of the daily requirement for animal protein, vitamins A and B2. A rather high level of cholesterol should be noted: a chicken egg weighing 40 g can contain about 80% of the normalized daily intake. The unfavorable properties of cholesterol, however, are largely neutralized by phospholipids.

Fish as a source of complete protein should take pride of place in the diet.

Thus, it is recommended to include lean meat and poultry (without skin) in the menu, consume fish, including fatty fish, at least twice a week; reduce the number of sausages, sausages and other similar products as much as possible due to the high content of animal fat in them. It is advisable to avoid frying them in a large amount of oil, preferring stewing, boiling, incl. steamed (cutlets, dumplings and other similar products). Lean meats are recommended to be consumed 2 times a day. At the same time, it is advisable to use 80-100 g of lean beef or lamb, or 60-80 g of pork, or 2 sausages, or 80-100 g of poultry, or 2 chicken eggs, or 80-100 g of fish at one time.

Fats, sweets, sugar

This group of products should be limited in every possible way in the formation of the diet.

These include butter, vegetable oils, lard, margarine, sour cream, confectionery, ice cream, sugar. It is recommended to choose confectionery products with a reduced content of fat and sugar, it is necessary to get rid of the habit of eating sweets between meals.

Of vegetable fats, preference should be given to soy and corn oils, for salad dressing use linseed, olive, cedar.

From animals - a small number butter and pork fat. Use lighter oils more widely.

Approximate daily recommendations for the consumption of fatty and sweet foods in their pure form may look like this: 1-2 tablespoons of vegetable oil, or 5-10 g of butter, or margarine for cooking; 3 chocolates, or no more than 5 caramels, or 5 tsp. jam, or honey, or 2-3 waffles, or 50 g of cake.

It is very important to understand that not a single food product, not one of the presented food groups can provide a person with a complete set of necessary nutritional and biologically active compounds. Therefore, representatives of each group should be present to some extent in the daily diet, contributing to the preservation and promotion of health.

Knowing the nutritional value and properties of the foods that we see on our table every day will help you to independently and more accurately create menus, choose products in the store when you go shopping. Also, to choose healthy food, we recommend that you familiarize yourself with the list of basic nutrition rules.

From the point of view of nutritional science, the whole variety of food products is divided into five main groups:

Grain products
Meat products and meat substitutes
Milk and dairy products
Vegetables and fruits
Fats, oils, sugar and sweets

The principle of division: according to natural origin, according to the characteristics of nutritional value. Therefore, legumes containing a large amount of protein are usually included in one group with meat products.

Grain products.

Grain products are important in the diet as a source of starch, protein, B vitamins, dietary fiber (fiber), iron and other minerals.

In Russia, the most consumed: wheat, rye, barley, oats, corn, buckwheat, rice.

Bread and bakery products.

Bread is never boring and contains almost everything you need for good nutrition essential nutrients. The well-known saying “Bread is the head of everything” is relevant at all times, since bread is an indispensable food for a person at any age, with the exception of infants.

Now there are varieties of bread baked from whole grains with the addition of bran, as well as varieties of bread from several cereals.

Why eat bread?

Bread products contain:

vegetable proteins
Carbohydrates (polysaccharides)
Vitamins B1, PP, B6, E, folic acid
Macro- and microelements (iron, phosphorus, magnesium)

Grain products are a source of B vitamins created by nature. The content of vitamins B, B6, PP, E and folic acid in the grain of wheat, rye, oats, barley and other cereal crops, it is balanced as if on purpose, in accordance with human needs.100 g of grain covers 30% of the daily requirement for each of these vitamins.

However, grain processing leads to significant losses of vitamins, minerals, and dietary fiber, which are removed along with the grain shell. The content of valuable nutrients in flour depends on the amount of bran particles remaining in it - the components of the grain shells.

The most valuable from the point of view of health is the flour obtained from whole grains, because the bran is not removed from it at all. Without going into technological details, we note that the less bran is separated from the flour, the coarser the grinding of the grain and the darker the flour in color.

Therefore, when choosing bread for your family, give preference to varieties in which important components are preserved as much as possible: whole grain, because. grain shells contain many vitamins and minerals, or the composition of the flour is enriched with bran.

You can diversify your diet by including multi-grain crackers, whole grain bread, whole wheat flakes, rye, etc. in the menu instead of slices of bread.

Note:

With bread, a significant part of the consumed table salt enters the body.

There is a common and completely erroneous belief that the consumption of bread is the cause of obesity. This is in complete contradiction to the scientific data on nutritional properties bread, and the mechanism of obesity.

Bakery products include a wide range of products obtained from flour with various additives that improve the taste - sugar, eggs, butter, margarine.

The calorie content of pastry increases significantly due to the high content of fat, eggs, sugar. If starch gives the main part of the calorie content in flour, then in confectionery- fats and simple sugars. Therefore, cookies, gingerbread, crackers, buns can be the cause of excess consumption of fat and sugar, which contributes to overeating and obesity.

Hence the rule: the less muffin is added to the dough, the more useful it is. Culinary skill is to make the dough more bland, but tasty.

You can use toppings for this. By the way, pies with fruit or any vegetable filling can be prepared not on pastry, but their taste is excellent!

Now let's analyze the calorie content and nutritional value of some bakery products. It should be remembered that all nutritional values are given per 100g of a product or dish.

The more fat and sugar in bakery products, the higher the calorie content of this product. At the same time, such important indicators as the amount of dietary fiber (dietary fiber) are significantly reduced in products based on premium flour.

Dietary fibers are complex carbohydrates that are not a source of energy. The reason is that digestive enzymes cannot digest them, as they digest, for example, starch. (The fibers found in grasses can be digested and used for energy by ruminants.) However, it has long been known that complex carbohydrates play an important role in the processes of digestion and the life of the body as a whole.

Dietary fiber reduces the rate of absorption of mono- and disaccharides in the intestines and, thereby, protects the body from high blood glucose and increased insulin synthesis, which stimulates the production of fats.

Fiber fibers increase the binding and excretion of bile acids from the body, reduce the absorption of cholesterol and fats in the small intestine, accelerate the production of the lipase enzyme in adipose tissue, under the action of which the breakdown of fat occurs, i.e. have a positive effect on fat metabolism.

Ballast substances, as dietary fiber is commonly called, ensure normal intestinal motility, biliary tract, prevent the development of constipation, hemorrhoids, and colon cancer.

If there is not enough fiber in the diet, then food slowly passes through the gastrointestinal tract, feces accumulate in the large intestine. This leads to the processes of decay in the intestines, the normal microflora is disturbed, which leads to the development of dysbacteriosis.

The use of dietary fiber is the basis for the prevention and treatment of obesity, atherosclerosis, coronary disease, cancer, diseases of the digestive system.

cereals

Cereals are obtained from various grain crops by removing the upper shells of the grain. The main Russian cereal dish is porridge.

Take note:

Dairy porridge or as a side dish can be consumed at any meal. But the proverb “You can’t spoil porridge with butter” from the point of view modern science- outdated. Porridge with butter is a sweet pastry. Therefore, when using this wonderful product, reduce the amount of oil and sugar.

Cereal products go well with milk and sour-milk products, since the microelements of cereals are in a bound state. In the presence of milk protein, potassium and magnesium become active elements, and this is very important for the normal functioning of the whole organism. Your heart will say: "Thank you so much" for a competent diet.

More than half of the annual world harvest of buckwheat falls on Russia and the CIS countries. Growing this crop does not require additional chemical fertilizers (buckwheat fields are classified as environmentally friendly).

smoke). The plant is not at all afraid of weeds, as it successfully displaces them.

Buckwheat protein contains an ideal composition of essential amino acids, which allows this "queen" of cereals to be a complete replacement for animal products in a vegetarian menu.

Buckwheat has been introduced into all therapeutic and preventive diets, even in cases where other cereals are forbidden to be consumed (for celiac disease). Buckwheat starch has the property of slowly releasing sugar, which allows patients to diabetes without restrictions to eat dishes containing buckwheat. Ready-made breakfasts (flakes, sticks) go well with fermented milk products.

So, the main distinguishing feature of buckwheat and flakes is a low glycemic index, which allows it to be successfully used in weight loss programs.

Oats and barley.

The most significant effect of soluble fibers of oatmeal and barley groats for a healthy diet is lowering cholesterol and blood sugar levels, improving the condition of the gastrointestinal tract.

Due to the content of polysaccharides, soluble and insoluble fibers in oat products, after taking them, a long feeling of fullness occurs. Those who want to lose weight can actively use them in their diet. The dietary fibers of this cereal, getting into the caecum and large intestine, are converted into compounds that serve as a nutrient medium for the microflora of the large intestine.

Rye.

The content of starch and protein in rye grain is less than in wheat, but the concentration of sugars and dietary fibers of both types (soluble and insoluble) is much higher. Rye contains the same macro- and micronutrients as other cereals, but it contains an order of magnitude more iron, manganese, copper, zinc, selenium, magnesium and even fluorine.

Millet.

Millet - millet seeds, peeled from the outer shell. In its composition, wheat groats are close to buckwheat.

Extruded cereal products.

Today, products under the brand name "ready breakfasts" are very popular. The most valuable in nutritional terms are grain products obtained by extrusion. This method consists in the rapid heating of soaked grain (cereals), which literally explodes when the temperature rises. Food components, primarily vitamins, are well preserved with extrusion technology, since the production cycle of exposure is very short.

Extrudates

do not require heat treatment (cooking), they are ready to eat, which preserves all the important components of cereals;
are easily soaked in the contents of the gastrointestinal tract and are easily digested and absorbed by the body;
As a rule, they contain only grains, without added sugar and fat, that is, a complete component of a healthy diet.

Petr Semenenko

MEDICALHEALTHLIFEBEAUTY SECRETS

In many books on sports, you can read "A good training system can eliminate the need for any kind of diet". We categorically disagree with this and declare with all responsibility that no training will ever compensate for careless nutrition.

FOUR FOOD GROUPS

IF you take old books about delicious and healthy food(old books were much more thorough than modern ones), you will read on the first pages that food products can be divided into four main groups: meat (including poultry and fish meat), dairy, vegetable and grain.

It was noted that only when a person consumes all these types of foods in sufficient quantities, his body is supplied with all the necessary nutrients and vitamins. If you remember school and analyze the range of products offered to you in school canteens, you will understand that the menu was compiled based on these principles.

PYRAMID OF NUTRITION

Since then, the idea of what a balanced diet should be has changed somewhat, although the division of food into four main groups is still often used. When dividing products into groups, rather general approaches are used without regard to the method of preparation. So, fresh ovoy salad and stir-fried ketchup would be considered in the same category: vegetable.

In accordance with this scheme, all products are collected in a dietary pyramid (see figure). The foods at the base of the pyramid, according to nutritionists, should account for the lion's share of our calories. This group includes cereals, flour products, rice, pasta, fruits and vegetables. Products such as meat (including poultry and fish meals), eggs, sugar and other sweets, dairy products, animal and vegetable fats occupy the top of the pyramid. The consumption of these products is recommended to be limited. This scheme is far from perfect. In particular, saturated animal fats and much healthier unsaturated vegetable fats do not separate.

At Harvard University, an alternative Mediterranean dietary pyramid was recently developed, in which vegetable oils (olive and sunflower) are indicated as the main fats needed for humans, while in the pyramid shown in the figure, developed by specialists from the Ministry Agriculture USA, meat and cheeses are considered to be the main strategic sources of fats for humans. In any case, modern nutritionists have abandoned the simple division of food into four large groups and are developing more detailed schemes that take into account the possibilities different products complement each other in nutrient composition. (Read more about the HEALTHY FOOD PYRAMID.)

For a balanced diet, it is important not only what you eat, but also in what quantity and what ratios. So, it is assumed that a portion of pasta will be equal to half a cup (a cup is a portion of a product with a volume of within 50 g), which does not correspond to those immense servings of pasta that you will be offered in any Italian restaurant.

The average composition and volumes of dishes and servings calculated for the dietary pyramid are shown below.

ANIMAL AND VEGETABLE FATS, SWEETS: use in limited quantities, i.e. as less as possible. According to many health organizations, these foods should account for no more than 30% of total calories.

MEAT (INCLUDING POULTRY AND FISH DISHES), DRY BEANS, EGGS AND NUTS: one dish corresponds to 60–100 g of cooked meat products, 1 egg, half a cup of boiled beans or 2 tablespoons of nuts (in the broadest sense - walnuts, forest, pine, peanuts, seeds, etc.).

MILK, YOGHURT AND CHEESE: one dish equals a cup of milk or yogurt - enough to fill a bowl of oatmeal for breakfast. Instead of milk, there may be a slice of cheese. It means ordinary cheese with a low fat content.

FRUIT: one dish corresponds to a small apple, banana or orange, half a cup of fruit or berry salad, three-quarters of a cup of fruit juice. It is preferable to use fresh rather than canned fruit or juice.

HERBS: One dish equals 1 cup of fresh ta leaves, half a cup of other greens, or half a cup of cereals, rice, or pasta.

REPLACEMENT PRINCIPLE

Reducing your calorie intake along with fat from 40% to 30% or even 20% sounds like the misanthropic plan of some evil dictator from a sci-fi WW3 horror movie. But to implement this program, you do not have to peck millet like a bird at all. Simply swapping out foods for foods that are just as tasty and nutritious will allow you to significantly reduce your fat intake.

NO matter what you read in the fitness literature, the question of the effect of physical activity on metabolism has not yet been definitively resolved. The answer largely depends on what type of exercise you are doing. Research suggests that aerobic exercise (running or climbing stairs) does not increase metabolic rate.