The value of fats for the human body. Fats: their role, functions and types

2 Video lectures on the topic: "The role of proteins, fats and carbohydrates in the human body"

Proteins, fats and carbohydrates play an important role in the human body.

Squirrels- complex substances, consisting of amino acids. They are an invariable part of the diet. This is the main building material, without which the growth of muscles and tissues in general is impossible. Proteins are classified into 2 categories:

F animal which comes from animal products. This category includes meat, poultry, fish, milk, cottage cheese and eggs.

Vegetable which the body gets from plants. It is worth highlighting here rye, oatmeal, walnuts, lentils, beans, soy and seaweed.

Fats - this is organic compounds, which are responsible for the "reserve fund" of energy in the body, are the main suppliers of energy during periods of food shortage and illness, when the body receives a small amount of nutrients or does not receive them at all. Fats are necessary for the elasticity of blood vessels, due to which beneficial elements quickly penetrate to tissues and cells, help to normalize the condition of the skin, nail plates and hair. Fats are found in large quantities in nuts, butter, margarine, pork fat, hard cheese.

Carbohydrates is the main source of energy for people. Depending on the number of structural units, carbohydrates are divided into simple and complex. Carbohydrates, called simple or "fast" carbohydrates, are easily absorbed by the body and raise blood sugar levels, which can lead to weight gain and poor metabolism.

Complex carbohydrates are composed of many linked saccharides, including tens to hundreds of elements. These carbohydrates are considered beneficial because, when digested in the stomach, they release their energy gradually, providing a stable and long-term feeling of fullness.

Also, vitamins and microelements play an important role in the body, which are not included in the structure of tissues, however, without their participation, many vital functions that occur in the human body would not be performed.

Almost all life processes in our body are dependent on what we eat. Fresh fruits are rich in carbohydrates. Excessive consumption of sweets, flour products, sugar should be avoided. Rational nutrition is essential - and this implies not only the timely use of deliciously prepared food, but also the inclusion in the daily diet of the optimal ratio of substances important for proper vital activity, such as proteins, fats, carbohydrates, vitamins and microelements. The maintenance of normal human activity depends on the harmonious combination of all these substances.

The main components of all living cells are proteins, fats, the functions and properties of these compounds ensure the vital activity of organisms living on our planet.

Fats are natural, complete esters of glycerol and fatty acids with one base. They belong to the lipid group. These compounds perform a number of important body functions and are an indispensable component in the human diet.

Classification

Fats, the structure and properties of which make it possible to use them in food, by their nature are divided into animal and vegetable. The latter are called oils. Due to the high content of unsaturated fatty acids in them, they are in a liquid state of aggregation. An exception is palm oil.

According to the presence of certain acids, fats are divided into saturated (stearic, palmitic) and unsaturated (oleic, arachidonic, linolenic, palmitoleic, linoleic).

Structure

The structure of fats is a complex of triglycerides and lipoid substances. The latter are phospholipid compounds and sterols. Triglyceride is an ester compound of glycerol and fatty acid, the structure and characteristics of which determine the properties of fat.

The structure of the fat molecule in general is displayed by the formula:

CHˉO-CO-R ''

CH2-OˉCO-R '' ',

In which R is a fatty acid radical.

The composition and structure of fats have in their structure three unbranched radicals with an even number of carbon atoms. most often represented by stearic and palmitic, unsaturated - linoleic, oleic and linolenic.

Properties

Fats, the structure and properties of which are determined by the presence of saturated and unsaturated fatty acids, have physicochemical characteristics. They do not interact with water, but decompose completely in organic solvents. They are saponified (hydrolyzed) if they are treated with steam, mineral acid or alkalis. During this reaction, fatty acids or their salts and glycerin are formed. Form an emulsion after vigorous shaking with water, an example of this is milk.

Fats have an energy value of approximately 9.1 kcal / g or 38 kJ / g. If we translate these values ​​into physical indicators, then the energy released at the consumption of 1 g of fat would be enough to lift a load weighing 3900 kg by 1 meter.

Fats, the structure of their molecules determines their main properties, have a high energy content when compared with carbohydrates or proteins. The complete oxidation of 1 g of fat with the release of water and carbon dioxide is accompanied by the production of energy twice as high as the combustion of sugars. For the breakdown of fats, carbohydrates and oxygen are required in a certain amount.

In humans and other mammals, fat is one of the most important energy suppliers. In order for them to be absorbed in the intestine, they must be emulsified with bile salts.

Functions

In the body of mammals, fats play an important role; the structure and functions of these compounds in organs and systems have different meanings:

In addition to these three main functions, fats have several private ones. These compounds support the vital functions of cells, for example, provide elasticity and a healthy appearance of the skin, and improve brain function. Cell membrane formations and subcellular organelles retain their structure and function due to the participation of fats. Vitamins A, D, E and K can be absorbed only in their presence. Growth, development and reproductive function are also highly dependent on the presence of fat.

The body's need

About a third of the body's energy consumption is replenished by fats, the structure of which allows solving this problem with a properly organized diet. The calculation of the daily requirement takes into account the type of activity and age of the person. Therefore, most of all fats are needed by young people leading an active lifestyle, for example, athletes or men who are engaged in hard physical labor. With a sedentary lifestyle or a tendency to be overweight, their number should be reduced to avoid obesity and related problems.

It is also important to consider the structure of fats. The ratio of unsaturated and saturated acids is essential. The latter, with excessive consumption, disrupt fat metabolism, the functioning of the gastrointestinal tract, and increase the likelihood of atherosclerosis. Unsaturated acids have the opposite effect: they restore normal metabolism, remove cholesterol. But abuse of them leads to indigestion, the appearance of stones in the gallbladder and excretory tracts.

Sources of

Almost all foods contain fats, and their structure can vary. The exception is vegetables, fruits, alcoholic beverages, honey and some others. Products are classified into:

Also important is fat, which determines the presence of one or another acid. On this basis, they can be saturated, unsaturated and polyunsaturated. The former are found in meat products, lard, chocolate, ghee, palm, coconut and butter. Unsaturated acids are found in poultry, olives, cashews, peanuts, olive oil. Polyunsaturated - in walnuts, almonds, pecans, seeds, fish, as well as in sunflower, flaxseed, rapeseed, corn, cottonseed and soybean oil.

Formulation of the diet

The structural features of fats require a number of rules to be followed when drawing up a diet. Nutritionists recommend adhering to the following ratio:

• Monounsaturated - up to half of the total fat;
• Polyunsaturated - a quarter;
• Saturated - a quarter.

In this case, vegetable fats should make up about 40% of the diet, animal fats - 60-70%. Elderly people need to increase the number of the former to 60%.

Trans fats should be limited or eliminated from the diet as much as possible. They are widely used in the production of sauces, mayonnaise, and confectionery. Fats exposed to intense heating and oxidation are harmful. They can be found in French fries, chips, donuts, pies, etc. Of this list, the most dangerous foods are those that were cooked in rancid or used oil many times.

Useful qualities

Fats, the structure of which provides about half of the total energy of the body, have many beneficial qualities:

• cholesterol promotes better carbohydrate metabolism and ensures the synthesis of vital compounds - under its influence steroid hormones of the adrenal glands are produced;
• about 30% of all heat in the human body is produced by tissue located in the neck and upper back;
• badger and dog fat are refractory, cure respiratory diseases, including tuberculous lesions of the lungs;
• phospholipid and glucolipid compounds are part of all tissues, are synthesized in the digestive organs and counteract the formation of cholesterol plaques, support the functioning of the liver;
• thanks to phosphatides and sterols, the constant composition of the cytoplasmic base of the cells of the nervous system is maintained and vitamin D is synthesized.

Thus, fats are an indispensable component in the human diet.

Excess and deficit

The fats, structure and function of these compounds are beneficial only when consumed in moderation. Their excess contributes to the development of obesity - a problem that is relevant for all developed countries. This disease leads to an increase in body weight, decreased mobility and a deterioration in well-being. The risk of developing atherosclerosis, cardiac ischemia, and hypertension increases. Obesity and its consequences more often than other diseases lead to death.

Deficiency of fats in the diet contributes to the deterioration of the skin, slows down the growth and development of the child's body, disrupts the functioning of the reproductive system, interferes with the normal metabolism of cholesterol, provoking atherosclerosis, and impairs the functioning of the brain and the nervous system as a whole.

Proper planning of the diet, taking into account the body's requirements for fats, will help to avoid many diseases and improve the quality of life. It is essential that they are moderately consumed, without excess and deficit.

Fats are included in a large group of organic compounds under the general name - lipids. This group also includes one more fat-like substance - lipoids.

Fats in living organisms are the main type of storage substances and the main source of energy. In vertebrates and in humans, about half of the energy consumed by living cells at rest is formed due to the oxidation of fatty acids that make up fats. Fats also perform a number of the most important functions in the body.

1. Fat forms protective layers for internal organs: heart, liver, kidneys and so on.

2. The membrane of all cells in the body is about 30% fat.

3. Fats are essential for the production of many hormones. They play an important role in the activity of the immune system, and this, as you know, is the body's internal self-healing system.

4. Fats deliver fat-soluble vitamins A, D, E and K.

From the foregoing, we can conclude that various diets that sharply reduce the amount of fat entering the body from food, as well as the constant use of low-fat food products, are harmful to health and will not contribute to the health of the body.

Important facts about fats

1. Rates of fat consumption individually. It is recommended to eat 1 - 1.3 grams of fat per 1 kilogram of body weight per day. For example, if your weight is 60 kilograms, then you need to eat 60 - 70 grams of fat per day.

2. Try to avoid foods high in saturated fat: fatty meats, sausages, fatty dairy products.

3. Reduce the amount of vegetable oils containing Omega-6: sunflower, corn, peanut.

4. Add oils containing Omega-6 to the diet: canola, flaxseed, hemp, soy and mustard.

5. Try to eat less fried foods. Use only refined oils for frying. Prefer olive oil.

6. Try not to consume trans fatty acids.

7. Be careful when buying sweets for children. Almost all confectionery (chocolate bars, waffles, biscuits, ice cream, etc.) contains margarine (hydrogenated vegetable oil), which is detrimental to children's health.

The role of fats in the brain

The main difference between humans and all other mammals is the large proportion of the brain in relation to the total weight. But the trouble is to have something, to not mean to be able to fully use it. This statement also applies to the brain - in order to use it to its full potential, it must be given the necessary nutrition.

According to medical research, human brain tissue is composed of about 60% fat. What is very important, the fats that enter the body with food affect the functioning of the human brain. Eating unhealthy oils and fats can lead to various abnormalities in the brain.

Currently, scientists have established that under optimal conditions, Omega-3 fatty acids and Omega-6 should enter the body in equal proportions, which was observed in our ancestors. Now the ratio of these acids in food has changed to 20 or even 30: 1, that is, for 30 grams of Omega - 6 there is only one gram of Omega - 3. This situation has developed for several reasons.

1. Increased consumption of oils rich in Omega-6 (sunflower, corn, sesame and so on).

2. The consumption of oils rich in Omega-3 (flaxseed, hemp, soy and so on) has decreased.

3. During production, oils began to undergo a hydrogenation process - margarine is obtained, which does not contain Omega - 3.

4. Fish of artificial cultivation appeared - with the help of special feed.

5. Due to the use of modern processing methods, cereals began to lose their core (embryo), rich in healthy fats.

All of these changes in eating habits have a strong negative effect on the functioning of the brain. If one of the fatty acids begins to prevail first in the diet, and then in the brain, this leads to disturbances in the functioning of the nervous system. If the brain does not receive a sufficient amount of the fats it needs, then its structure begins to change, which leads to a number of deviations in the work of this organ and the whole organism. For example: aggression, autism, Parkinson's disease, hostility towards others, hyperactivity, depression, retinal diseases, mental and physical retardation, drug abuse, migraines, brain tumors, paralysis, multiple sclerosis.

As we can see, by supplying the body with the right fats, we take care not only of the gastrointestinal tract, but also of the full functioning of the brain and the health of the whole organism.

The effect of fats on children and adolescents

During growth and development, the body reacts most strongly (in the form of various diseases) to the negative factors of the surrounding world. As we have already decided, fat is a difference between fat and what kind of fats enter the body of a child and adolescent directly depends on his health, both mental and physical. The greatest harm is caused by trans fatty acids, which easily enter the body if it is not controlled - literally with breast milk.

Research results show that, on average, a woman's milk contains about 20% trans fatty acids of the total fatty acids. Basically, trans fatty acids enter the body of a woman with food, and then penetrate into breast milk. The trouble is that, in parallel with the increase in trans fats in the body of a woman and a child, the amount of essential, beneficial fatty acids, for example, Omega-3, decreases.

What should be done to reduce the amount of trans fats entering the child's body?

Strictly monitor what foods a woman eats before conception, during pregnancy and during breastfeeding.

Get enough antioxidants.

Ensure that the body has the correct balance of Omega-3 fatty acids.

In preschool age, the parents are fully responsible for the future health of children. They must closely monitor their diet to ensure that it contains a minimum of trans fats. At preschool age, the brain develops very rapidly, and if a child receives high-quality fats, this will not only have a positive effect on his health, but also on mental abilities.

School-aged children and adolescents are the most active consumers of trans fats. A donut alone can contain up to 13 grams. A standard packet of chips contains 7 to 8 grams of trans fatty acids. 100 grams of French fries contains 8 grams of trans fatty acids. As a result, it turns out that a teenager eats 30-50 grams of bad fats per day. And this happens at a time when the brain develops most actively and nerve cells must constantly form many new connections.

The role of polyunsaturated fatty acids in baby food

In the first years of life, the regular intake of substances with food that the body cannot synthesize is of great importance for the growth of a healthy child. These ingredients include polyunsaturated fatty acids (PUFA).

The main functions of PUFA of classes Omega-3 and Omega-6 are participation in the formation of phospholipids of cell membranes and the synthesis of biologically active substances - tissue hormones: prostacyclins, prostaglandins, leukotrienes and thromboxanes. These substances play an active role in the regulation of the functions of the whole organism, especially the cardiovascular system.

Long-chain polyunsaturated fatty acids play a special role in the formation and functioning of the central nervous system and visual analyzer in the fetus and infants. It is known that the human brain is 60% fat. At the same time, at least 30% of the total amount of fats is accounted for by long-chain PUFAs. They are included as a structural component in the composition of cell membranes. The distribution of PUFA in tissues is significantly different. For example, docosahexaenoic acid is found in large quantities in the membranes of photoreceptors, accounting for 50% of all fatty acids in the outer segment of rods, which is necessary for the highest photochemical activity of rhodopsin.

Of greatest practical interest are 2 classes of PUFA: Omega-3 and Omega-6. The key representative of omega-6 fatty acids is long-chain arachidonic acid, which is part of the phospholipids of the cell membranes of platelets of endothelial cells. Arachidonic acid makes up 20-25% of all fatty acids of phospholipids of cell and subcellular membranes.

Eicosapentaenoic and docosahexaenoic acids, representatives of the Omega-3 family of long-chain fatty acids, are also present in the composition of phospholipids, their amount is approximately 2-5%. Insufficient consumption and (or) a violation of the synthesis of these acids leads to a change in the fatty acid composition of lipids of biological membranes, causing a deviation of a number of indicators of their functional state (permeability, enzymatic activity, fluidity, etc.).

Long-chain omega-3 polyunsaturated fatty acids ensure the normal development of the child's sensory, motor, behavioral and other functions. Docosahexaenoic acid, for example, is essential for the normal development of the nervous system and the visual analyzer of the fetus and newborn. With a high content of docosahexaenoic acid in the diet of a pregnant woman, an increase in its level is noted both in blood plasma and in mother's milk.

This is probably why children of mothers who received docosahexaenoic acid during pregnancy and lactation have a higher visual acuity. There are also other known positive effects, in addition to the effect on visual acuity. In particular, docosahexaenoic acid helps to improve the cognitive abilities of the child and reduces the incidence of bronchitis.

Since a person needs an intake of long-chain PUFAs from the outside with food, a deficiency of these fatty acids in the diet can lead to deviations in physical and neuropsychic development in the first year of life.

The possibility of using solid fat (lard) in the diet of patients with chronic pancreatitis during the period of remission

Most dietary recommendations for pancreatitis should help keep the pancreas as calm and less active as possible. These nutritional recommendations should definitely be taken into account in patients with hypersecretory form of chronic pancreatitis. However, the use of such food for people with the most common hyposecretory form raises questions. The use of products that do not stimulate the pancreas and create "artificial rest" are unlikely to create conditions for the normalization of the organ. The situation is aggravated by the fact that in the treatment of chronic pancreatitis, drugs are widely used to replace the functions of the pancreas - this contributes to its even greater atrophy.

Today, nutritionists recommend that in chronic pancreatitis, sharply reduce (60 - 70 grams per day) the consumption of fats with the maximum restriction of refractory fats. It is recommended to eat natural fats in the form of refined vegetable oil and butter.

Long-term adherence to such a diet leads to a deficiency of certain nutrients and can increase the secretory insufficiency of the pancreas, since the organ is in a state of "artificial functional calm" for a long time.

Patients who follow a strict diet lose the necessary body weight and observe a decrease in physical strength.

For these reasons, many modern nutritionists do not recommend completely excluding solid fats from their diet after an exacerbation of the disease. According to studies, after discharge from the hospital, patients with chronic pancreatitis who began to eat 50 grams of solid fat per day did not experience bouts of illness for 3 to 12 months. People felt better, gained from 3 to 5 kg of weight and their physical and mental performance increased.

Pork lard has certain advantages over butter: high energy value (820 kcal versus 740 kcal per 100 grams of product), contains 2 times less cholesterol (95 mg versus 180 mg per 100 grams of product), contains 10 times more linoleic acid ( 8.5 g versus 0.84 g per 100 g of product) and at the same time contains arachidonic acid and vitamin B 1, which is practically absent in butter, has 2 times more lecithin phospholipids, which normalize the metabolism of fats in the body.

Thus, a strict ban on the use of solid fats of animal origin should be prescribed to patients with chronic pancreatitis only during an exacerbation.

Conclusion: the inclusion of a limited amount of solid fat (lard) in the diet of patients with chronic pancreatitis without disturbing the patency of the Wirsung duct and without exacerbation, contributes to a more balanced diet and does not cause an exacerbation of the disease.

The role of unsaturated fatty acids in fats

Fat is a combination of glycerin and various fatty acids. The function and value of fat supplied with food depends on those fatty acids that are included in its composition.

Polyunsaturated fatty acids: linoleic, linolenic and arachidonic - are indispensable nutrients, since they are not synthesized in the body and therefore must be supplied with food. According to their biological properties, these acids belong to vital substances and are even considered as vitamins (vitamin F).

The physiological role and biological significance of these acids is diverse. The most important biological properties of unsaturated acids are their participation as structural elements in such highly active complexes as phospholipids, lipoproteins, and others. They are an essential element in the formation of cell membranes and connective tissue.

Arachidonic acid precedes the formation of substances involved in the regulation of many vital processes of platelets and prostaglandins, which scientists attach great importance to as substances of the highest biological activity. Prostaglandins have a hormone-like effect, which is why they are called "tissue hormones", since they are synthesized directly from membrane phospholipids. The synthesis of prostaglandins depends on the supply of these acids by the body.

The relationship of unsaturated fatty acids with cholesterol metabolism has been established. They contribute to the rapid conversion of cholesterol into folate and their excretion from the body.

Unsaturated fatty acids have a normalizing effect on the walls of blood vessels, increase their elasticity and reduce permeability.

The relationship between unsaturated fatty acids and the metabolism of B vitamins has been established.

With a deficiency of unsaturated fatty acids, the intensity and resistance to unfavorable external and internal factors decrease, reproductive function is inhibited, the deficiency of unsaturated fatty acids affects the contractility of the myocardium, and causes skin damage.

Vegetable fats have a high energy state as they are formed directly during photosynthesis in the green parts of plants and then are deposited in fruits and seeds.

Nut oil is a source of highly digestible emulsified fats. If you eat enough nuts, you don't need to add any oils to your diet.

It is desirable to use the oil obtained by cold pressing. Refined oil devoid of trace elements and vitamins should be excluded. In addition, acids in refined oil are easily oxidized and oxidized products accumulate in the oil, which lead to its deterioration.

Animal fats contain toxic impurities, which, when broken down, enter the body. After all, the adipose tissue of both animals and humans is a "sump", since it has the least metabolism. For this reason, the body, in order to get rid of toxins, deposits them in adipose tissue, where they are stored.

Cardiovascular and Omega-3 Polyunsaturated Fatty Acids

Interest in fish oil as a factor affecting the heart and blood vessels arose in the seventies of the last century after a study showed a low mortality rate from coronary heart disease (coronary heart disease) among the coastal Eskimo population of Greenland, which predominantly feeds on marine fish and marine animals.

It was found that the cardiovascular system of the Eskimos is not prone to atherosclerosis and coronary heart disease due to fish oil, which contains Omega-3 polyunsaturated fatty acids (eicosapentaenoic and docosahexaenoic).

Another interesting study was conducted over 23 years among Japanese people living in Honolulu (Hawaii, USA) and it was found that the negative effect of smoking on the heart (early development and more severe course of CHD) is leveled in people who regularly eat fish 2 or more times a week. ...

In another open-label study of 1015 patients with myocardial infarction, half of whom were advised to increase their fish intake after 2 years, a 29% reduction in CHD mortality was found compared to the 2 group that did not receive fish.

A large study on the effects of fish oil on the heart and blood vessels was carried out in Italy in 2003. Half of the 11,323 patients with myocardial infarction received 1 gram of omega-3 polyunsaturated fatty acids for 3 - 5 years, the rest received standard treatment from their doctor. During this time, 1031 patients (9.1%) died. Already after 3 months from the beginning of observation in patients who took fish oil in addition to the usual treatment, fewer deaths were recorded than in the control group (1.1% versus 1.6%). By the end of the observation, the reliability of the difference in favor of the patients of the main group became even higher (8.4 versus 9.9). The risk of death in the main group decreased by 21%.

In 2003, the American Heart Association recommended taking 1 gram of Omega-3 polyunsaturated fatty acids in encapsulated fish oil to reduce the risk of sudden death.

Experimental studies have identified properties of fish oil that may be important in suppressing atherosclerosis and improving the cardiovascular system.

1. Strengthening the production of anti-inflammatory prostaglandins.

2. Decrease in the level of leukotriene B 4.

3. inhibition of the function of neutrophils and monocytes.

4. The use of fish oil in the form of a concentrate of omega-3 polyunsaturated fatty acids leads to a decrease in triglyceride levels by 21-79%

6. Fish oil moderately lowers blood pressure in hypertension and decreases the hypertensive response to norepinephrine administration.

7. The blood clotting time is lengthened, the aggregation ability of platelets decreases, the viscosity of whole blood decreases, the fluidity of the membrane and the erythrocytes themselves increases, which improves their permeability in the blood flow.

The positive effect of fish oil on the body is multifaceted, therefore it is used to treat autoimmune and immunological diseases - bronchial asthma, lupus erythematosus and atopic dermatitis. The anti-inflammatory effect of fish oil provides additional grounds for its use in atherosclerotic diseases for the purpose of treatment and prevention.

Additional articles with useful information

Description of fat metabolism in humans

Fats in your diet are often remembered, since it is this nutritional ingredient that is responsible for many diseases. If the metabolism of fats is not disturbed in the body, then their presence in the diet will not harm even an elderly person.

Description of different options for metabolic disorders in humans

The metabolism does not stop for a second and has a very complex regulation system, which can naturally malfunction. But often people are in a hurry to ascribe to themselves the diagnosis of metabolic disorders, confusing the true disease with regular violations of the regime and rules of healthy eating.

Substances that from a chemical point of view belong to triglycerides. They are a backup energy source. However, with insufficient physical activity and, accordingly, insufficient expenditure of them, an excess of triglycerides is the biochemical basis for the development of obesity.

Fats: their role, functions and types

Fats are one of the three main components of human nutrition, along with carbohydrates and proteins. Without them, it is impossible to create a correct and healthy diet. However, it is about the fat content of products that the greatest number of questions arise. How much fat should you have? How to choose them correctly? And what does it mean to reduce their consumption? MedAboutMe understands all aspects of healthy eating.

Adipose tissue in adults

The balance of adipose, muscle and bone tissue in the human body is one of the main conditions for a long and healthy life. It should be borne in mind that the norms of the optimal ratio vary greatly, depending on gender, age, and often physical activity. It is also important where exactly the fatty layer accumulates, because depending on its type, it will affect the body in different ways.

You cannot rely on weight alone to measure body fat correctly. The fact is that adipose tissue is not as dense as muscle and bone, so it will take up more volume. An illustration of this can be the equal weight of 100 or more kilograms of a heavyweight athlete and an overweight person. Therefore, to correctly assess the percentage of body fat, you can use a special scale with an analyzer, which shows not only the total weight, but also the content of muscle, adipose, bone tissue, as well as water.

A more accurate diagnosis can be carried out using computed tomography, but since this is a rather expensive and rare method, it is used only in the treatment of obesity. You can check the size of the subcutaneous layer using a special caliper device (the width of the skin fold is measured). This method does not give an accurate idea of ​​the types of fat and its percentage in the body, but it can still help in the initial diagnosis.

Fat in the body of men

The accumulation of fat is directly related to metabolic processes: the slower they are, the larger the body fat will be. Even if a person consumes the same amount of food and adheres to the same level of physical activity. With age, metabolism slows down, so the rate of a healthy ratio of fat, muscle and bone mass changes in the direction of increasing the volume of the former.

The following percentage of fat is considered the norm:

• 15-30 years old - 12-23%.
• 30-50 years old - 13-26%.
• 50 years and more - 16-28%.

The female body, from a physiological point of view, does not differ in such endurance and strength as the male. Already during puberty, the girl's figure is formed in such a way that the fat layer develops much more actively than in the guy's body. At the same time, muscle and bone tissue, on the contrary, does not grow so actively. It is due to the higher fat content that women have more rounded figures that are distinguished by smooth shapes.

The percentage of fat in the female body should normally be as follows:

• 15-30 years old - 17-28%.
• 30-50 years old - 19-31%.
• 50 years and more - 21-33%.

Percentage of body fat in pregnant women

The above norms do not apply to pregnant women, their adipose tissue can increase up to 30-35%, which is also not a pathology. The total weight gain during childbearing is 9-14 kg or 16-21 kg for twins. This mass is distributed as follows:

• 3-4 kg - fetal weight.
• 2 kg - uterus and amniotic fluid.
• 1 kg - an increase in the mammary glands.
• From 1.5 kg - an increase in blood volume.
• 1.5-2 kg - additional water.
• Up to 4 kg is normal - an increase in adipose tissue.

If the weight is gaining more than the norm, most often its increase occurs precisely due to fat. And this can affect the well-being of a woman, since excess weight and weight put additional stress on the cardiovascular system and kidneys. Also, it is excess fat that is a risk factor for the development of diabetes in pregnant women.

The correct ratio of different types of tissues in the body should also be monitored by those who are planning a pregnancy. Body fat is associated with the endocrine system, in particular, can significantly affect the production of female sex estrogens. As a result, with a deficiency (fat content less than 15%), menstruation often stops (amenorrhea) and the inability to conceive a child. Infertility is also recorded in women with the 3-4th stage of obesity with a fat percentage of more than 40%. In the case of deficiency, in the absence of other health disorders, fertility is restored after normalization of weight. But with excess body weight, diseases, for example, polycystic ovaries, can become the causes of infertility. And it will be much more difficult to compensate for their consequences.

Adipose tissue in children

In infants, brown fat plays a special role, which regulates the body's adaptation mechanisms to new environmental conditions. It is these fats in children of the first weeks of life that are responsible for thermoregulation. With a strong cooling of the body, an adult begins to tremble involuntarily - such a muscle contraction accelerates blood flow, improves heat production, thereby helping to avoid hypothermia. However, in newborns, this mechanism has not yet been developed, and it is brown fat that is responsible for maintaining body temperature. In the body, it is not more than 5%, however, it is located in strategically important places - in the area of ​​the shoulder blades, neck, kidneys, on the shoulders. When the ambient temperature drops too low, it is he who prevents the vital organs from freezing - the heart, kidneys, warms the abdominal cavity. Starting from the second week of life, tremors, as a reaction to cold, begin to prevail, and the role of brown fat is gradually weakening.

Fats for children play an especially important role, since the rate of metabolic processes in a child is very high. It should be borne in mind that, nevertheless, the percentage of this tissue is normally less than that of adults. For example, for schoolchildren it should be 11-20%. After the onset of puberty, at the age of 13-14, the percentage of boys and girls begins to differ.

Childhood obesity can be a symptom of various diseases. So, excess weight often accompanies type 1 diabetes mellitus, thyroid problems and other metabolic diseases. It is also believed that it is in childhood that overweight affects health most adversely:

• The joints are worn out, the musculoskeletal system may suffer.
• Excess fat affects the work of the heart and can cause myocardial infarction even at a young age.
• If obesity is diagnosed in a teenager, it is fraught with delayed puberty. This is especially true for boys, who, due to the excessive production of estrogen by adipose tissue, develop in a female pattern.
• Life expectancy is reduced. Scientists insist that people who were obese in childhood do not live to be 60 years old. Various diseases of the cardiovascular system become the cause.

For weight control in children, dietary fat should not be ruled out or drastically reduced. In the event that the child is inclined to be overweight, it is necessary to pay more attention to simple carbohydrates - starchy foods, sweets, pasta, carbonated waters and so on. It is these products that contribute to an increase in body weight, therefore, they must be strictly controlled. From other types of food, it is recommended to exclude those in which hidden fats predominate:

• Fast food. Including French fries and any deep-fried food.
• Chocolate.
• Confectionery products with creams: protein, custard and others.
• Sauces: ketchup, mayonnaise, etc.

The priority should be good fats of natural origin:

• Vegetable oils (olive, sesame, sunflower).
• Fish and seafood (if there are no allergic reactions).
• Nuts.
• Fermented milk products with medium and high percentage of fat (2.5-9%), milk 3.2% fat.

Types of adipose tissue

The main function of adipose tissue in the body is to store energy. It is from these cells that the required amount is released if the body does not receive enough nutrition or the level of glucose in the blood falls for other reasons. For example, due to active physical activity.

Human adipose tissue is not of the same type, it is distinguished both by location and by type. Therefore, when assessing the harm / benefit of body fat, it is necessary to take into account not only its percentage, but also other factors.

Subcutaneous fat

Subcutaneous fat is the deepest integumentary tissue of a person, which is located under the skin. Moreover, its thickness will vary significantly depending on the location. For example, there is the least amount of subcutaneous fat on the hands, but the thighs and abdomen, as a rule, have a thick layer. Also, a significant layer can be in the shoulder area, on the back, legs. That is why, when you gain weight, these areas increase in volume the most.

The main function of subcutaneous fat is to keep the body from hypothermia. It is this layer that protects vital organs, and also participates in the process of thermoregulation - from here signals about the temperature of the external environment come to the hypothalamus.

The increase in the volume of subcutaneous fat is clearly noticeable as the mass builds up in all areas. However, according to its characteristics, this type of tissue is quite inert and damages health mainly by providing additional stress on the heart. Due to the addition of mass, the network of blood vessels increases, and for movement it is necessary to expend more strength and energy, therefore the heart is forced to work constantly in an enhanced mode. This can lead to various disorders, including heart failure, arterial hypertension, and more.

If the subcutaneous fat is distributed relatively evenly, then the visceral fat is concentrated exclusively in the abdominal cavity. It is often also referred to as internal, as this tissue envelops the organs.

Belly fat has a number of important functions, but it is the increase in fat that is considered the most dangerous to health. First of all, the visceral layer is responsible for:

• Thermoregulation and frost protection of internal organs.
• Maintaining the organs and their correct placement in the abdominal cavity.
• Protection from damage, bruises, various concussions.
• Endocrine function (more so than subcutaneous fat). It is this type of tissue that is most hormonally active, in particular, capable of producing a certain amount of female sex hormones.

If the belly fat has grown too much, it can significantly harm your health.

• The layer can put pressure on organs, interfere with their normal functioning. Problems with the digestive tract are often observed - heartburn, constipation, heaviness in the abdomen.
• Excessive production of female hormones estrogen affects the entire endocrine system. In men, testosterone synthesis is suppressed, which can lead to erectile dysfunction and infertility.
• Visceral fat affects the functioning of the cardiovascular system. People with high levels of it have a high level of "bad" cholesterol in the blood - the main culprit in the development of atherosclerosis.
• The risk of inflammatory processes increases, including various complications after surgery.

Unlike the subcutaneous layer, the growth of which is easily noticeable, internal fats can also exceed the norm in relatively thin people. So, there is often an increase in the volume of the abdomen, a poorly defined waist. Actually, it is this parameter that is one of the possible symptoms of metabolic syndrome - a condition dangerous for the development of type 2 diabetes mellitus, as well as various heart diseases. A person needs examination and treatment if the waist circumference exceeds the following indicators:

• For women - 80-85 cm.
• For men - 90-94 cm.

White and brown adipose tissue

The composition of fat stored in the body also differs in structure. According to the type of cells, doctors distinguish two types of adipose tissue:

• White.

A basic tissue made up of large cells that can store fat. In full, they reach a size of 50 microns. If the body needs additional energy, it gets it from the white tissue. At the same time, the cells themselves are not destroyed, but, releasing the fat stored in them, they simply decrease in size. It is with this that the differences in body types are associated - the size of the fat layer (the actual number of cells) is different for everyone. And accordingly, everyone will have their own opportunities for increasing volumes. People with a large number of cells of this tissue are considered to be overweight. White tissue forms the basis of the subcutaneous layer and the visceral layer (belly fat), and may even be present in the muscles.

• Brown.

It is in the human body in a very small volume, at birth it reaches the highest percentage - about 5%. Its main task is to provide thermoregulation when muscle contraction is impossible. Therefore, brown tissue is well developed in hibernating animals. In humans, it is most relevant as fats in children, namely for babies who are still developing the ability to tremble when the temperature drops. But in the body of an adult, it was not detected for a long time. After small patches of this fat were found, scientists believed that brown adipose tissue was inactive in adults. And only in 2008 it was proved that it can perform its functions not only in the body of an infant. However, for its activation, a strong decrease in the ambient temperature is required.

Fats (triglycerides) are organic substances, one of the main components in human nutrition. This is a fairly large group, which is represented by different types of compounds, as well as a component found in food of animal and plant origin.

Proteins fats carbohydrates

A good human diet should always include proteins, fats,. It depends on how exactly these components relate to each other whether a person will gain weight, or, conversely, lose weight. And most importantly, due to what these processes will take place - due to fat, water or, for example, muscles.

The correct selection of foods from the groups of proteins, fats, carbohydrates makes it possible to form a diet, which can become a prevention or even a cure for certain diseases. First of all, it concerns the health of the cardiovascular system, gastrointestinal tract, pancreas.

Normally, the ratio of proteins, fats and carbohydrates should look like this:

• 30-50% carbohydrates.
• 25-35% protein.
• 25-35% fat.

At the same time, when losing weight, the ratio changes mainly in the ratio of proteins and carbohydrates - the number of the former is brought to 50%, and the latter is reduced to 20%. Fats remain in approximately the same amount. But for gaining body weight, their percentage can be reduced to 15-25%, and the carbohydrate content can be increased to 60%.

Fats are the most energy-intensive substances. If 1 g of proteins and carbohydrates contains an average of 4 kcal, then there will be 9 kcal in fats. Despite this, the increase in body weight and adipose tissue is directly related to the consumption of carbohydrates - the main sources of energy. It is its excess that accumulates in the cells of the white adipose tissue.

The amount of fat in the diet

Since triglycerides perform a number of important functions in the human body, their low content in the diet leads to various consequences. Lack of fat (less than 15% of the total diet) is manifested by the following symptoms:

• Peeling, sensitive, irritation-prone skin.
• Dull nail plates.
• Thin and brittle hair, lack of shine.
• Deterioration of vision.
• Joint pain.
• Low stress resistance.
• Hormonal disorders (infertility may occur in women).

In the event that even good fats in the diet make up more than 35-40%, there is an excess of them, which can adversely affect health. In particular, with constant nutrition of this type, a dangerous liver damage can develop - fatty disease. With this disease, excess fats gradually accumulate in the tissue of the organ, and do not have time to be excreted by the body. In an advanced stage, liver failure develops, which can be fatal. Fatty disease is quite common, in Russia it develops in 26.1% of the population, in the USA - in 32%, in Israel - in 46%.

An excess amount of fat can also lead to the following diseases:

• Atherosclerosis, ischemic heart disease.
• Stroke.
• Gout.
• Cholelithiasis.

Many people underestimate the fat content of the foods they eat, so an overabundance of these substances is quite common. Fats in confectionery, sweets, bakery products, sauces, fast food, various snacks and snacks are not counted. Signs of excessive use of fat in the diet can include:

• Oily skin prone to inflammation, especially on the face.
• Oily seborrhea.
• Heaviness in the stomach.
• Constipation.

Functions and benefits of fats

The main function of fats is to store energy. Carbohydrates are a source of glucose, which is immediately used by the body and has little storage capacity (it is deposited in the form of glycogen in small quantities). But fats are just long-term reserves of energy that can accumulate in significant amounts.

Other important functions of these substances include:

• Triglycerides are involved in metabolic processes. In particular, they are an important building material for cells - it is from them that membranes are formed.
• Fats are an important component in stopping the development of inflammatory processes.

One of the essential fats in the human body -. And although it is often considered to be the key culprit in the development of atherosclerosis, one of its types, high-density lipoproteins (HDL, "good" cholesterol), is just important for the normal functioning of blood vessels. The benefit of fat is that it is able to neutralize "bad" cholesterol, which forms atherosclerotic plaques, so a high level of HDL (above 1.55 mmol / L) is considered one of the main factors in the prevention of atherosclerosis and coronary heart disease.

Also, it is fats that are important for the absorption of certain vitamins. A certain amount of these substances can be stored in adipose tissue.

Fats in foods can come in different forms. Some of them are beneficial for humans, therefore, are preferred as a component of a healthy diet. Others, on the other hand, can be harmful. It depends primarily on the structure of the triglyceride itself. Conventionally, all fats can be divided into:

• Natural (saturated and unsaturated).

These substances perform different tasks and exhibit different activities in metabolic processes. Traditionally, unsaturated fats are considered good fats. However, it is still proven today that both species should be present in the human diet.

• Artificial origin (trans fats).

Unsaturated fat derivatives with proven health risks. In the body, they are practically inert, in fact, they are immediately deposited in fat reserves. Nutritionists, gastroenterologists and cardiologists recommend eliminating trans fats from the diet completely.

A properly composed diet should contain animal and vegetable fats, and there should be more of the latter than the former. In animal products, in particular in natural fermented milk products, a certain percentage of fat will always be present. Yoghurts, cottage cheese, kefir and other products with 0% fat content are considered harmful, since the fat from them is separated artificially, often replaced by various additives or sugar. Therefore, low-fat foods cannot be classified as a healthy diet.

Composition of fats

The composition of fats includes carbon and hydrogen, and how a particular triglyceride will behave in the body depends on how these elements are bound.

They got their name because the structure contains the maximum possible number of hydrogen attached to carbon - they can no longer attach anything to themselves. Therefore, when it enters the body, they are passive, in fact, it is a simple piece of energy that is quickly converted into accumulated fat reserves.

• Unsaturated fat.

They differ from the previous ones in that they are able to actively interact with other substances, since the composition of these fats suggests incomplete carbohydrate-hydrogen bonds. These substances include, in particular, the most useful fats Omega-3 and Omega-6. They take an active part in metabolic processes and are completely broken down in the body. In comparison, saturated fat is only 25-30% utilizable.

• Trans fatty acids (trans fats).

They are obtained as a result of the processing of unsaturated acids, during which open bonds are closed, and the composition of fats begins to resemble saturated ones. This process is called hydrogenation - the artificial addition of hydrogen to carbon. According to its characteristics, the product turns out to be quite harmful.

Unsaturated fats

Most often, unsaturated fats contain the following acids:

• Palmitoleic.
• Oleinic.
• Linoleic.
• Linolenic acid.
• Arachidonic.

By consistency, these are liquid oils, which are most often found in herbal products. The only exception is fish oil, the benefits of which are often mentioned in nutrition.

Speaking about unsaturated acids, doctors often distinguish two large groups - Omega-3 and Omega-6. Both the first and the second must be present in the human diet. At the same time, relatively recently, they started talking about the fact that healthy fats should not only become part of the diet, but also be included in its composition in a certain ratio. One of the latest studies, conducted in 2010 by French scientists, proved that excessive consumption of Omega-6 with a lack of Omega-3 can lead to obesity. The ideal ratio of such acids is considered to be 2 (or 4) Omega-6: 1 Omega-3. Modern man most often receives them in a ratio of 20: 1.

Omega-6s are found in high amounts in key vegetable oils. The good omega-3 fats, on the other hand, can be found in foods like:

• Flaxseed or oil.
• Sesame oil.
• Fish: mackerel, herring, salmon.

Omega-9 (oleic acid) is also isolated in the group of unsaturated fats. However, unlike Omega-3 and Omega-6, it is not irreplaceable, since it can be synthesized by the human body. Therefore, despite the benefits of fats, foods containing omega-9 are not required in a healthy diet.

Saturated fats contain the following acids:

• Stearic acid.
• Margarine.
• Palmitic.
• Nylon.
• Oil.

By their structure, these are fats that remain solid at room temperature. Most of them are of animal origin, however, as is the case with unsaturated acids, there are exceptions - coconut, palm and cocoa butter.

When saturated acids enter the bloodstream, they can adhere to the walls of blood vessels, clog them, interfere with blood flow, and complicate the course of a number of metabolic processes. It is the use of such fats in large quantities that can cause the development of a number of diseases:

• Diabetes.
• Atherosclerosis, including coronary artery disease - ischemic heart disease, leading to heart attacks.
• Hypertension.
• Heart failure.
• Liver damage, including non-viral hepatitis and fatty hepatosis.
• Diseases of the gastrointestinal tract.

At the same time, it is still not recommended to completely exclude saturated fats from the diet. In the course of research, a number of important functions of these substances have been proven. For example, they can stimulate testosterone production. Therefore, today the American Heart Association recommends that 7% of all calories consumed go to saturated fat. In practice, the required portion can be obtained by consuming fermented milk products or lean meats.

Trans fats

Trans fats are an artificial invention, fats obtained during the hydrogenation (addition of hydrogen) of unsaturated acids. As a result, the composition of fats changes, and they acquire the characteristics of saturated. At the same time, unlike natural compounds, trans fats generally do not carry any benefit to the body. They practically do not break down in the human body, in fact, they simply clog the bloodstream, can stick to the walls of blood vessels, slow down metabolic processes, and are quickly deposited in the form of adipose tissue.

Moreover, a 2015 study at McMaster University suggests that it is trans fats, and not natural saturated fats, that contribute to the development of heart and vascular diseases, provoke insulin resistance (insulin resistance) and, as a result, diabetes mellitus 2- th type.

Despite the significant harm to health, the use of these fats is very common in the food industry. Today, they are added to almost all sweets, many types of baked goods, snacks, and various instant meals or ready-to-eat foods (for example, deep-fried fish sticks). It is easy to determine the presence of such fats in a product by its shelf life - it is trans fats that differ from natural counterparts in that they may not deteriorate for a long time.

According to previous WHO recommendations, the amount of this type of fat in the diet should not exceed 1%. However, since 2009, the World Health Organization has revised the standards and recommends completely eliminating the use of fats of artificial origin.

Fats in food

In order to choose the right food, you need to know which of them contain different types of fats. It should be borne in mind that most often in both plant and animal food, different types of fatty acids are present. They are classified as saturated or unsaturated, relying solely on the predominant component.

The overwhelming majority of animal fats in foods are saturated. These include:

• Meat of different fat content.
• Bird.
• Lard and lard.
• Egg yolk.
• Milk and fermented milk products.
• Butter.
• Sour cream, cream.
• Cheeses, white and yellow.

Since animal fats should be present in a healthy diet in small quantities, the most correct decision would be to opt for lean meats, white cheeses, and dairy products.

• Trim off all visible white fat.
• Remove the skin from the bird.
• Boil the meat or grill it, so some of the calorie fat will go away. On the other hand, when frying it, it is saturated with additional oil.
• Combine meat with foods high in fiber - herbs, vegetables. This will help to quickly remove excess fat from the body, improve bowel function.

Fish oil: benefits

The exception to saturated animal fats is fish oil, which is beneficial because it contains unsaturated acids. This is why this product is considered by nutritionists separately from other species in this category.

Fish oil is useful primarily in that it contains a sufficient amount of Omega-3. The highest content of necessary acids is observed in such varieties (the amount per 100 g of the product is indicated):

• Atlantic salmon (up to 2.15 g).
• Sardines (up to 2 g).
• Mackerel (up to 1.85 g).
• Atlantic herring (up to 2 g).
• Trout (up to 1.15g).
• Tuna (up to 1.51 g).
• Salmon (up to 1.4 g).

It is recommended to eat fish freshly cooked (baked, steamed) - this way it is possible to maintain a high content of healthy omega-3 fats. But in canned and smoked products, their number is significantly reduced. You should also be careful to introduce salted fish into your diet. Due to its high salt content, it can harm the cardiovascular system, cause hypertension, and disrupt the body's water balance. Fatty fish are recommended to be consumed at least 2 times a week. Together with Omega-3, in such products, a person receives vitamins A, D and other useful substances. Seafood also contains a small amount of fat, but it is customary to refer to it as a dietary meal, since the amount of unsaturated acids does not exceed 0.6 g per 100 g.

As a supplement, fish oil is useful for the following indications:

• Lack of vitamins A and D.
• Eye diseases (as recommended by a doctor).
• Dry skin, tendency to redness and irritation.
• Brittle hair, hair loss.

Fish oil can be taken for no more than 3-4 weeks and is best in the autumn-winter period, when the lack of vitamin D is especially noticeable.

Animal fats in meat

Saturated solid fats predominate in meat. A healthy diet involves the use of only dietary meats with the exception of such products:

• Mutton.
• Pork.
• Salo.
• Lard.
• Duck.

Since meat is an important source of essential proteins, it is advisable to eat it daily; to form the menu, choose the following varieties:

• Bird, better turkey.
• Veal.
• Beef.

In order to reduce the amount of fat with saturated acids, it is recommended not to fry the meat, but to boil it, bake it, and steam it. When preparing the first courses, it is better to boil the meat separately and add it to the dish at the end of cooking - fatty broths can also be harmful to health. It is not recommended to add vegetable fats (sunflower and other oils) when cooking meat - this significantly increases the total calorie content of the product. It should also be borne in mind that meat can remain in the stomach for up to 6 hours (for example, pork), so it is better to eat such dishes no later than lunchtime.

• sunflower,
• olive,
• corn,
• linseed,
• soy.

Despite the fact that the overwhelming majority of vegetable fats are unsaturated acids useful for the body, it should be borne in mind that the final product - oil - contains almost 100% pure fat. It belongs to the category of high-calorie foods, therefore it is recommended only in small portions. 1 tsp for dressing salads, it is quite enough to replenish the body's needs for unsaturated acids of vegetable origin.

The use of oils for frying is considered harmful, and especially for deep-fried cooking, in this case the oil burns out, the benefits of fats are questioned. In addition, during the cooking process, the product is too saturated with fat, the calorie content can increase 3-4 times from the initial one.

Vegetable fats are also found in some fruits and seeds:

• avocado,
• nuts (walnuts, cashews, hazelnuts, brazil nuts),
• sunflower and pumpkin seeds,
• mustard seeds,
• peanuts and soybeans,
• poppy seed
• olives,

• Coconut oil,
• Palm oil,
• cocoa butter (used to make chocolate),
• palm kernel oil.

In the preparation of various dishes, fats have always been used quite actively. However, with the development of the food industry, trans fats have gained particular popularity. For the first time they managed to get them back in 1890, the technology was patented in 1902 and since then has been used in literally all areas of the food industry.

Such popularity of trans fats is due to their main quality - when using this type, the shelf life of the product can be extended. One of the most famous representatives of the category is margarine. Also, the use of fats of artificial origin is found in such products:

• Fast food (for frying and deep frying): French fries, hamburger patties, fish sticks, strips.
• Snacks: chips, croutons, etc.
• Confectionery pastries: cakes, pastries, muffins, croissants.
• Chocolates and chocolates.
• Ice cream.
• Mayonnaise.

The second most popular food processing industry is animal saturated fat in foods. Their great content is noted in:

• Smoked meats and sausages.
• Canned meat.
• Confectionery creams based on sour cream.

Vitamins in Fats: Fat-Soluble Vitamins

All vitamins necessary for the full functioning of the body are divided into two large groups: fat-soluble and water-soluble. The splitting and assimilation of the former is impossible without a fatty medium; they are also able to accumulate in the subcutaneous fat layer and belly fat.

It is because the body can store fat-soluble vitamins that vitamin deficiencies in this category are relatively rare. Symptoms of severe hypervitaminosis appear only with vitamins A and D, while others are excreted in the urine or neutralized by the body. However, their use in the form of special supplements should be coordinated with the attending physician.

Vitamin A

Vitamin A is one of the key antioxidants that prevents aging and can protect against the development of cancer. It is necessary for full-fledged bone growth, prevents visual impairment. A person gets vitamins A with fats from fish oil, cod liver, egg yolk. Such fats are especially useful for children, since they ensure the full development of the body. Vitamin A is also found in carrots and pumpkins, and is better absorbed if vegetables are consumed with sour cream or vegetable oil.

• Symptoms of vitamin deficiency: blurred vision, stunted growth in children and adolescents, poor dull hair, loose skin.

Vitamin D is essential for bone growth and calcium absorption by the body. It is against the background of its lack that rickets are observed in children, improper skeletal formation and other abnormalities. Vitamin D can be synthesized by the body itself under the influence of sunlight, therefore, most often its lack is felt in cloudy months, in winter, when daylight hours are reduced.

Vitamin with fats can be obtained in dairy and fermented milk products, butter. Vitamin D supplements are often recommended for children, but consideration should be given to whether there is an obvious indication for such treatment. After all, hypervitaminosis in a child of the first year of life can be accompanied by poor appetite, general intoxication and even loss of consciousness.

• Symptoms of vitamin deficiency: rickets in children and osteoporosis in adults, fragility of bones (for example, frequent fractures).

Vitamin E

The main function of vitamin E is to protect cell membranes from damage. It is responsible for the elasticity of the skin, the shine of the hair, and its normal and healthy growth. Like vitamin A, E is a strong antioxidant, which means it helps to maintain youth. Symptoms of hypervitaminosis are practically not observed, since the body is able to neutralize excess substances. Vitamins with fats can be obtained by including vegetable oils, almonds, peanuts, beef liver, milk, eggs in the diet. Also E is found in greens, apples, rose hips, Brussels sprouts.

• Symptoms of vitamin deficiency: dry dull skin, a feeling of tightness after washing, brittle nails and their poor growth, hair loss, possibly a lack of coordination of movements.

Vitamin K

Vitamin K is involved in hematopoiesis, in particular, helps blood clotting in open wounds and internal bleeding. In addition, the substance is involved in the neutralization of food toxins, protects the liver from damage. Like other fat-soluble vitamins, K has antioxidant effects. You can get these vitamins with fats by supplementing the diet with soy and olive oil, walnuts, and pork liver. K is also found in large quantities in green tea, leafy vegetables, broccoli, and spinach.

• Symptoms of vitamin deficiency: bleeding, non-healing wounds, bleeding gums, anemia, against which there is pallor of the skin, weakness, fatigue.

Fats and weight control

Proper fat burning involves a number of important rules and an integrated approach to the process. So, be sure to pay attention to nutrition, physical activity, balance of rest and stress.

In a healthy adult body, the ratio of tissues should be as follows:

• Men: fat - no more than 23%; muscles - more than 41%; bones - an average of 3.3 kg.
• Women: fat - no more than 28%; muscles - more than 33%; bones - about 2.4 kg.

It is also necessary to monitor the balance of water, it should be at least 45-50% in the body of an adult.

The main goal of losing weight is burning fat, not losing pounds through water or muscle mass. Therefore, these indicators must be monitored. If the weight is lost due to water, then the volumes will return very quickly. And the loss of muscle mass threatens with serious diseases, including heart problems.

Diet for weight loss is a key component of the fight against excess body fat. It is due to correctly selected foods and diet that you can rebuild the body to burn fat. The fact is that since it is fat that is responsible for the reserve energy reserve, the body does not begin to use it right away. And if a person makes some mistakes while losing weight, he can block the process altogether, slow down the metabolism and switch to the accumulation mode. As a result, returning to a normal diet will only lead to more weight gain.

The main mistakes with a fat burning diet:

• Rare food.

Eating 1-2 times a day does not speed up the metabolism, but, on the contrary, makes it slow down. Skipping breakfasts, lunches, and refusing to eat snacks is not suitable for an effective diet.

• Fasting.

Acts on metabolic processes even worse than rare meals.

• Large portions.

With them, too much glucose can enter the bloodstream, and the pancreas will produce insulin to compensate for it. And this hormone inhibits fat burning.

• Refusal of water.

It also slows down the metabolism, in addition, the body can suffer from toxins.

• Eating 0% fat products.

Sugar is often added to such cheese curds, fermented milk drinks and yoghurts instead of fat. And just it has a much greater effect on body weight gain. In this case, all the benefits of fats that such foods carry are lost.

Healthy fats

It is necessary to remember about the ratio of proteins, fats, carbohydrates in a diet for weight loss:

• Proteins - 40-50%.
• Fat - 30-40%.
• Carbohydrates - 10-20%.

It is the decrease in carbohydrates in the diet that can affect the consumption of adipose tissue. But the fats themselves cannot be reduced, it is just important to choose the right type of them. Priority should be given to foods containing unsaturated fatty acids - vegetable oils and fish. To reduce the calorie content of a dish, you can use not ready-made oils, but add grains. For example, sesame seeds or some flax can be used as a salad dressing. Other important products include:

• Fatty fish (contain the necessary Omega-3): salmon, mackerel, etc. When dieting, their number should not exceed a portion of 100 g twice a week.
• Seafood: shrimp, mussels, squid and more. With a low calorie content, they contain fatty acids and trace elements necessary for the body.
• Nuts: cashews, almonds, hazelnuts, etc. Can be used as an addition to meals or as part of a snack. It is best to eat raw nuts rather than roasted nuts.

Also, a weight loss diet can include healthy animal fats that contain saturated acids. However, their percentage should be significantly lower than the products listed above - no more than 10% of the total diet. Among the suitable options:

• Diet meats - beef, veal. All meat should be free of visible fat.
• Poultry - chicken and turkey. Before cooking, you need to remove the skin, but it is better to use white meat - breast.
• Fermented milk products with medium fat content. For yoghurts and cottage cheese - no more than 5%, and for drinks - about 2.5%.

Fat Burning Rules

The amount of body fat will only decrease if a person consumes fewer calories than they expend. However, a diet that is too "hungry" can negatively affect your health. Therefore, only a partial reduction in calorie content is optimal. Normally, a person needs from 2000 to 3000 kcal per day. With a diet, the figure can be reduced to 1600-1800 kcal.

Important to remember:

• Fractional nutrition in small portions allows you to reduce the total calorie content of the diet, as well as speed up metabolic processes.
• Too fatty food (consuming excessive amounts of oils, lard, fatty meats) can significantly affect the total number of calories. If 1 g of protein and carbohydrates contains approximately 4 kcal, then fats - 9 kcal.
• Sauces such as ketchup, mayonnaise, and sweet dressings can double the calorie content of a dish.
• Products containing trans fats (fast food, confectionery, etc.) are not only very high in calories, but can also slow down metabolic processes. Once in the bloodstream, such fats are inactive, can stick to the walls of blood vessels, and be harmful to health.
• Fats are best combined with simple carbohydrates - greens, fresh vegetables, fruits. Whole grain bread is acceptable.

When it comes to fat burning workouts, there are three things to consider - intensity, duration, frequency.

• Intensity.

Fat reduction is best done with cardio. They can be any workouts conducted at a heart rate of 60-70% of the maximum. For each age, the MHR (maximum heart rate) is calculated individually according to the scheme 220 minus the number of full years. For example, at the age of 30, training should be carried out with a heart rate of 114-133 (220-30 = 190 MHR. 60% - 114, 70% - 133). Less intense workouts for burning fat do not work as efficiently, and as the load increases, activities can affect the state of the cardiovascular system. In the event that training is conducted under the guidance of a trainer, he can calculate the intensity change mode during one lesson. It also helps to utilize fat mass.

• Duration.

With physical exertion, the body needs more energy, but fat stores do not begin to be consumed immediately. Blood sugar is involved first. When levels drop, the body turns on the glucose stored in the liver - glycogen. And only when its reserves are used up, training for burning fat begins - energy begins to be released from fat cells. As a rule, this occurs 20-25 minutes after the start of the lesson at optimal intensity. Therefore, the duration of the workout should not be less than 30 minutes, ideally 45-60 minutes.

• Frequency.

Since the decrease in the amount of body fat is directly related to the rate of metabolic processes, exercise should also help to speed up the metabolism. Best of all, this happens if sports are regularly performed - in this way the body is included in a certain rhythm and in the future is able to quickly rebuild under increased loads (connect different methods of obtaining energy, including the expenditure of visceral and subcutaneous fat). The optimal frequency is classes at least 4 times a week when combining different levels of intensity, 5-7 times a week with cardio loads.

A person chooses the time of training for burning fat individually. It is believed that it is best to spend it in the morning, but "owls" may well shift classes to the evening.

It is customary to call fats a group of simple lipids that can be utilized by the human body and have common structural features. Fats, some lipids, and their constituent parts are responsible for many processes of normal human life.

Functions of fats in the body

Physiology, medicine, biochemistry are intensively developing in parallel with the emergence of new instrumental research capabilities. Additional scientific data are constantly emerging, taking into account which the main functions of fats in the body can be represented in the proposed set.

• Energy... As a result of oxidative breakdown from 1 gram of fat, 9 kcal of energy is indirectly formed, which is significantly higher than the analogous figures for carbohydrates.

• Regulatory... It has been established that as a result of metabolic reactions, 1 g of fat in the body synthesizes 10 g of "internal" water, which is more correctly called endogenous. The water that we get with food and drinks is called "external", exogenous. Water is an interesting substance that tends to unite into groups - associates. This is the difference in the characteristics of water that has undergone melting, purification, boiling. Similarly, the quality of water synthesized in the body and received from the outside differ. Endogenous water must be synthesized without fail, although its role has not yet been finally established.

• Structural-plastic... Fats, alone or in combination with proteins, carbohydrates, participate in the formation of tissues. The most important is the layer of cell membranes, consisting of lipoproteins - structural formations of lipids and proteins. The normal state of the lipid layer of the cell membrane ensures metabolism and energy. So the structural and plastic function of fats in the cell is integrated with the transport function.

• Protective... The subcutaneous layer of fat performs a heat-preserving function, protects the body from hypothermia. This is clearly seen in the example of children swimming in the cool sea. Babies with a small layer of subcutaneous fat freeze very quickly. Children with normal body fat can take water treatments for much longer. The natural fatty layer on the internal organs protects them to some extent from mechanical stress. A small layer of fat normally covers many organs.

• Providing... Natural fats are always mixtures containing additional biologically active substances. The role of fats in the body lies in the parallel provision of components important for physiology: vitamins, vitamin-like compounds, sterols, and some complex lipids.

• Cosmetic and hygienic... A thin layer of fat on the skin gives it firmness, elasticity, and protects against cracking. The integrity of the skin, which does not contain microcracks, excludes the ingress of microbes.

Composition of fats

Fats are a group of substances consisting of one or more esters of high molecular weight carboxylic acids and an alcohol - glycerol. Acids containing more than 4 carbon atoms are usually called higher fatty acids. The composition of fats varies depending on the source of excretion. In addition to these esters, natural fats may contain a small amount of free high molecular weight acids, fragrances, pigments.

According to the structural features of acid residues, the entire group is usually divided into saturated and unsaturated fats.

• In saturated fats, all carbon atoms in the acid residue are linked to each other only by single bonds. The smallest saturated acid found in fats is called butyric acid. With prolonged storage, the ester bond can be destroyed, acids are released. Free butyric acid has a pungent odor, bitter taste. This is one of the reasons for the deterioration of the quality of fat during long-term storage.

Important! Saturated higher carboxylic acids predominate in animal fats.

Acids with a greater number of carbon atoms and a mass of molecules than butyric acid are most common in natural fats, for example, palmitic, stearic. Palmitic acid was first isolated from palm oil, its content in which reaches 50%. Stearic acid was first extracted from pig lard, the name of which in Greek became the basis for the name of the acid. All saturated acids are poorly soluble in water, which complicates the functions of fats in the cell.

• Unsaturated fats are esters with a significant content of unsaturated macromolecular acids.: oleic, linoleic, linolenic, arachidonic. The term "unsaturated" is due to the presence of double bonds between the carbon atoms in such molecules. In ordinary language, we can say that such substances are not completely saturated with hydrogen. For ordinary consumers, it is not the structural features that are important, but the properties originating from them.

Important! All unsaturated fats are found mainly in plants and have low melting points.

Under normal room conditions, they are in a liquid state. Unsaturated acids are usually subdivided into groups: oleic acid and structurally similar, linoleic acid and the like, linolenic acid with homologues, arachidonic acid. The last three groups have more than one double bond in the molecule. Therefore, they are called polyunsaturated (PUFA). The name of this complex of acids, vitamin F, is considered obsolete. Now, acids of the linolenic type are often called omega-3, such as linoleic and arachidonic - omega-6 acids.

Physiological role of polyunsaturated fatty acids

• The structural function is to form cell membranes.

• The plastic role is played in the formation of connective tissue, the surface of nerve fibers.

• Anti-sclerotic function is reduced to the ability to remove excess cholesterol from the blood vessel cavity. Fats and cholesterol must enter the body in a strictly defined ratio. Excess cholesterol coming from the outside, in conjunction with that synthesized inside the body, can provoke vascular changes.

• PUFAs increase the body's protective resources in relation to external influences, for example, viruses, microbes, adverse environmental factors.

• For the normal functioning of the cardiovascular system, it is important to have physiological indicators of blood coagulation. PUFAs contribute to the normalization of coagulability, which tends to increase with age.

• In the scientific literature there is information about the ability of PUFAs to break down some types of malignant cells.

• From arachidonic acid, with the participation of enzymes, prostaglandins are formed, which are referred to as hormones and hormone-like substances. Prostaglandins have a diverse regulatory effect, in particular, they indirectly improve the breakdown of fats in the body.

PUFAs are irreplaceable and should be included in the daily diet.

Sources of vegetable and animal fats

All food products are obtained from animals and plants. Fats are no exception. More than 600 examples of different fats are now known. The prevailing (more than 400) amount is plant substances. 80 species - animal fats, more than 100 species - fats of inhabitants of reservoirs. Sources of vegetable and animal fats are varied, to a great extent determined by culinary traditions, place of residence, climate, and the level of income of the population.

• Part of the fat is visible visually. These are butter and vegetable oils, lard, animal fats in meat, margarines.
• Some fats in foods are invisible. They are evenly distributed in meat, confectionery, dairy products, bread, fish, cereals, nuts.

How much fat do you need per day?

The need of each person should be determined taking into account many circumstances: age, type of activity, area of ​​residence, type of constitution. When playing sports, it is advisable to consult a specialist who can take into account all individual characteristics. It is important to remember that animal fats and cholesterol come in parallel with food, make up a diet taking into account all components.

The answer to the question "How much fat does each person need to absorb per day?" can be presented in the form of the following list:

• the total amount of all fats -80-100 g;
• vegetable oils - 25-30 gr;
• PUFA - 2-6 g;
• cholesterol - 1 g;
• phospholipids - 5 gr.

In general, the fat content in the daily diet should be about 30%. Residents of the northern regions can increase the fat content in their daily diet by up to 40%.

The maximum amount of fat is contained in refined vegetable oils (up to 99.8%), in butter - up to 92.5% of fat, in margarines - up to 82%.

• It must be remembered that one of the methods for producing margarines is to saturate vegetable oils with hydrogen. The process is called hydrogenation. In this case, isomers are obtained in the product that have a negative physiological effect - trans-isomers. Recently, a different method of margarine production has been used - modification of vegetable oils. In this case, no harmful isomers are formed. Margarine was originally invented in France in the late 19th century to feed the poor and the military. If possible, margarine should be excluded from the diet.

In dairy products, the fat content can reach 30%, in cereals - 6%, in hard cheeses - 50%.

Given the importance of PUFAs, remember the sources of their content.

• The maximum amount of essential acids, primarily arachidonic, is found in the fat of fish. The ideal supplier of this acid is fish liver.
• A lot of PUFAs are found in vegetable oils. The content of linoleic acid in corn oil reaches 56%, in sunflower oil - 46%.
• The specific gravity of PUFA does not exceed 22% in lard, chicken, goose fat. Olive oil contains 15% of essential acids.
• In butter, most animal fats, in milk fats, PUFAs contain little, up to 6%.

Cholesterol is on the list of essential components of natural fats recommended for daily nutrition. We get the right amount by eating eggs, butter, offal. They should not be abused.

Phospholipids, which are complex lipids, must be present in food. They contribute to the transportation of fat breakdown products in the body, their effective utilization, prevent fatty degeneration of liver cells, and normalize metabolism in general. Phospholipids are found in large quantities in the yolk of eggs, liver, milk cream, sour cream.

Excess fat in food

With an excess of fat in the daily diet, all metabolic processes are deformed. An excess of fats in food leads to the predominance of accumulation processes over splitting reactions. Fatty degeneration of cells occurs. They cannot perform physiological functions, which provokes numerous disorders.

Lack of fat in food

If there is little fat, the energy supply of the body is disrupted. Some part can be synthesized from the residues of molecules formed during the utilization of proteins and carbohydrates. Essential acids cannot be formed in the body. Consequently, all the functions of these acids are not realized. This leads to a loss of strength, a decrease in resistance, a violation of cholesterol metabolism, and hormonal imbalance. An absolute lack of fat in food is rare. The lack of useful components of fat can manifest itself if the rules for combining dietary fats are not followed.