Interesting facts about fats. Lipids - what are they? Lipids: functions, characteristics Why are lipids needed in the body

The body produces most of its lipids on its own; only essential fatty acids and soluble vitamins come from food.

Lipids are a large group organic matter, consisting of fats and their analogues. Lipids have similar characteristics to proteins. In plasma they are found in the form of lipoproteins, completely insoluble in water, but highly soluble in ether. The exchange process between lipids is important for all active cells, since these substances are one of the most important components of biological membranes.

There are three classes of lipids: cholesterol, phospholipids, and triglycerides. The most famous among these classes is cholesterol. The determination of this indicator, of course, has the maximum value, but nevertheless, the content of cholesterol, lipoproteins, and triglycerides in the cell membrane must be considered only comprehensively.

The norm is the LDL content in the range of 4-6.6 mmol/l. It is worth noting that healthy people this indicator may change taking into account a number of factors: age, seasonality, mental and physical activity.

Peculiarities

The human body independently produces all the main groups of lipids. The cell membrane does not form only polyunsaturated fatty acids, which are essential substances and fat soluble vitamins.

The bulk of lipids are synthesized by epithelial cells small intestine, liver. Individual lipids are characterized by association with specific bodies, tissues, and the rest are found in all cells and tissues. Most of the lipids are contained in nervous and adipose tissue.

The liver contains from 7 to 14% of this substance. In diseases of this organ, the amount of lipids increases to 45%, mainly due to an increase in the number of triglycerides. Plasma contains lipids combined with proteins, which is how they enter organs, cells, and tissues.

Biological purpose

Lipid classes perform a number of important functions.

1. Construction. Phospholipids, combining with proteins, ensure the formation of membranes.
2. Cumulative. The oxidation of fats produces a huge amount of energy, which is subsequently used to create ATP. The body accumulates energy reserves mainly in lipid groups. For example, when animals fall asleep for the entire winter, their body receives everything necessary substances from previously accumulated oils, fats, bacteria.
3. Protective, heat-insulating. The bulk of fat is deposited in the subcutaneous tissue, around the kidneys and intestines. Thanks to the accumulated layer of fat, the body is protected from cold and mechanical damage.
4. Water-repellent, lubricating. The lipid layer on the skin maintains the elasticity of cell membranes and protects them from moisture and bacteria.
5. Regulating. There is a connection between lipid content and hormonal levels. Almost all hormones are produced from cholesterol. Vitamins and other cholesterol derivatives are involved in the metabolism of phosphorus and calcium. Bile acids are responsible for the absorption and digestion of food, as well as the absorption of carboxylic acids.

Exchange processes

The body contains lipids in the quantities determined by nature. Taking into account the structure, effects and conditions of accumulation in the body, all fat-like substances are divided into the following classes.

1. Triglycerides protect soft subcutaneous tissues, as well as organs from damage and bacteria. There is a direct connection between their quantity and energy conservation.
2. Phospholipids are responsible for metabolic processes.
3. Cholesterol and steroids are substances needed to strengthen cell membranes, as well as to normalize the activity of the glands, in particular, the regulation of the reproductive system.

All types of lipids form compounds that ensure the maintenance of the body's vital processes and its ability to resist negative factors, including the proliferation of bacteria. There is a connection between lipids and the formation of many extremely important protein compounds. It is impossible to work without these substances genitourinary system. Failure of a person's reproductive capacity may also occur.

Lipid metabolism involves a connection between all of the above components and their complex effect on the body. During the delivery of nutrients, vitamins and bacteria to membrane cells, they are transformed into other elements. This situation accelerates blood supply and, due to this, the rapid supply, distribution and absorption of vitamins supplied with food.

If at least one of the links stops, the connection is disrupted and the person experiences problems with the supply of vital substances, beneficial bacteria and their distribution throughout the body. This violation directly affects the process of lipid metabolism.

Metabolic disorder

Every functioning cell membrane contains lipids. The composition of molecules of this kind has one unifying property - hydrophobicity, that is, they are insoluble in water. Chemical composition Lipids include many elements, but the largest part is occupied by fats, which the body is able to produce independently. But irreplaceable fatty acids usually enter it with food products.

Lipid metabolism occurs at the cellular level. This process protects the body, including from bacteria, and occurs in several stages. First, lipids are broken down, then they are absorbed, and only after that the intermediate and final exchange occurs.

Any disruptions in the process of fat absorption indicate a disorder in the metabolism of lipid groups. The reason for this may be an insufficient amount of pancreatic lipase and bile entering the intestines. And also with:

• obesity;
• hypovitaminosis;
• atherosclerosis;
• stomach diseases;
• intestines and other painful conditions.

When the villous epithelial tissue in the intestine is damaged, fatty acids are not fully absorbed. As a consequence in stool A large amount of fat accumulates that has not gone through the breakdown stage. Feces become a specific grayish-white color due to the accumulation of fats and bacteria.

Lipid metabolism can be corrected with the help of a dietary regimen and drug treatment prescribed to reduce LDL levels. It is necessary to systematically check the content of triglycerides in the blood. Also, do not forget that human body does not require large accumulation of fats.

In order to prevent disruptions in lipid metabolism, it is necessary to limit the consumption of oil, meat products, offal and enrich the diet with fish and seafood of low fat content. As a preventive measure, changing your lifestyle will help - increasing physical activity, sports training, rejection of bad habits.

They are organic compounds insoluble in water. They consist of fatty acid molecules connected in a chain of hydrogen and carbon atoms. If the carbon atoms are connected to each other by a strong bond, then such fatty acids are called “saturated”. Accordingly, if the carbon atoms are loosely bonded, then the fatty acids are unsaturated. The most important fatty acids for the human body are arachidonic, linoleic, and oleic fatty acids.

Division by chemical formula for saturated and unsaturated acids was developed quite a long time ago. Unsaturated ones, in turn, are divided into polyunsaturated and monounsaturated. Today it is known that saturated acids in our food can be found in pates, meat, milk, eggs. And unsaturated ones are found in olive, peanut, and sunflower oil; fish, goose and duck fat.

The term “lipids” refers to the entire spectrum of fat-like substances extracted with fat solvents (chloroform, ether, gasoline).

Lipids include triacylglycerol esters. These are substances in which glycerol binds to three fatty acid residues. Lipids include oils and fats. Oils contain a large amount of unsaturated acids and have a liquid consistency (with the exception of margarines). Fats, on the contrary, have a solid structure and contain large amounts of saturated acids.

Depending on their origin, lipids are divided into two main categories:

1. Vegetable fats (olive oil, nut butter, margarine, etc.).
2. Animal fats (found in fish, meat, cheese, butter, cream, etc.).

Lipids are very important for our nutrition, since they contain many vitamins, as well as fatty acids, without which the synthesis of many hormones is impossible. These hormones are an essential part nervous system.

When fats combine with “bad” carbohydrates, metabolism is disrupted, and as a result, most of them are deposited in the body as fatty layers.

As a rule, in our diet there is an excess of fat - fried fatty foods, in particular fast food, are becoming more and more popular and familiar. At the same time, food may well be tasty, even if you refuse sunflower oil and butter when preparing it.

Some of the lipids directly affect the increase in cholesterol levels in the blood. Cholesterol can be roughly divided into “good” and “bad”. Target healthy eating- dominance of “good” cholesterol over “bad” cholesterol. The overall blood level of this substance should be normal. If there is too much cholesterol, then it is deposited on the walls of our blood vessels and disrupts blood circulation, which disrupts the trophism of organs and tissues. And insufficient blood supply, in turn, leads to serious disruption of organ functioning. The main danger is the possibility of a blood clot breaking off from the wall and being carried by the blood flow throughout the body. His blood clot will clog the blood vessels of the heart, causing instant death. Everything happens so instantly that there is simply no chance of helping and saving a person.

Not all fats increase the amount of “bad” cholesterol in the blood; some of them, on the contrary, lower its level.

• Fats that increase cholesterol levels are found in butter, lard, meat, cheese, smoked and dairy products, and palm oil. These are saturated fats.
• Fats that almost do not contribute to the formation of cholesterol are found in eggs, oysters, and poultry meat (without skin).
• Fats that help lower cholesterol are vegetable oils: olive, rapeseed, corn, sunflower.

Fish oil prevents the occurrence of cardiovascular diseases, and does not play any role in cholesterol metabolism. In addition, it reduces triglyceride levels and therefore prevents the formation of blood clots. As a source of fish oil, those varieties of fish that are the most fatty are recommended: tuna, herring, chum and salmon, sardines, mackerel. In pharmacies you can also find fish oil in capsules as a dietary supplement.

Saturated

Frequent consumption of saturated fats causes serious harm to health. Sausages, lard, butter and cheese should not form the basis of the diet. By the way, saturated fatty acids are found in both palm and coconut oil. When buying products in a store, pay attention to the composition of the ingredients included in them. Palm oil- a frequent “guest” in our diet, although we don’t always know about it. However, some housewives will use it for baking instead of margarine. Meat contains stearic acid, which is contraindicated for the body in large quantities. The amount of fat in the daily diet should not exceed 50 grams. The optimal nutritional balance should consist of 50% monounsaturated fatty acids, 25% polyunsaturated and 25% saturated.

Most people consume too much saturated fat at the expense of unsaturated fat. Of these, about 70% are “invisible” (sausages, aperitif sets, cheeses, chips, and, of course, meat), and 30% are “visible” (this is everything that can be used for frying dishes and spreading on bread) .

Those fats that the body has not used remain in reserve in the body and, when combined with sugars, become the main cause of excess weight. And only just physical exercise and a balanced diet can correct this situation. Therefore, it is extremely important to adjust the intake of fatty acids according to their expenditure.

Monounsaturated

This type of fat is found in vegetable oils, and its main component is oleic monounsaturated acid. Monounsaturated fats are neutral in relation to the body and do not affect either the tendency to thrombosis or the level of cholesterol in the blood.

Olive oil is great for cooking because it holds up well high temperatures(actually up to 210°C), and at the same time retains a significant part of its valuable properties. It is advisable to buy unrefined, cold-pressed oil, and the darker the color it is, the better. It must be stored in a dark and cool place.

To obtain one liter of oil you need 5 kg of black olives. The cold pressing technique retains most of the vitamins and minerals in the oil. mineral salts: copper, phosphorus, magnesium, calcium, potassium, copper, iron. Interesting fact: the balance of lipids in olive oil is almost the same as in breast milk.

Of all the oils, olive oil is the best absorbed, and it also helps relieve constipation and liver failure. Another one of his useful property is that it can neutralize the intoxication of the body after drinking alcohol. Recent studies have shown that olive oil increases calcium absorption levels. This means that it is indispensable in the diet of children at the age when their bone apparatus is formed and developing.

Oleic acid is found in: olive oil (77%), rapeseed oil (55%), peanut oil (55%), grape seed oil (41%), soybean oil (30%), sunflower oil (25%), in wheat germ oil (25%), in walnut oil (20%).

Polyunsaturated

They consist of two groups, in which active substance is the so-called essential fatty acid. Since the body cannot produce it on its own, this acid must come from food.


Main sources: cereal sprouts (up to 50% fatty acid content), corn, cereals, brown rice, and oils.

Linoleic acid (Omega-6) is found in: sunflower oil (57%), soybean oil (55%), grape seed oil (54%), walnut oil (54%), wheat germ oil (53%) , in pumpkin (45%), sesame (41%), peanut (20%), rapeseed (20%), olive (7%).

Linolenic acid (Omega-3): in flaxseed oil (55%), walnut oil (13%), canola oil (8%), wheat germ oil (6%), soybean oil (6%), sesame oil (1 %), olive (0.8%). Omega-3 is also found in fish.

Flaxseed oil is very rich in omega-6 and omega-3 unsaturated fatty acids, which are necessary for cell building. It softens the skin, helps the body fight allergies, protects brain and nerve structures, and stimulates the production of hormones. It must not be heated and cannot be cooked on it. Flaxseed oil is added exclusively to ready-made cooled dishes: soups, cereals, salads, vegetables.

Fish and fish oil are a valuable source of omega-3 fatty acids. It is these acids that our body needs most. They are very useful for brain activity. However, the current ecology is such that it is advisable to give a child sea fish, and not pure fish oil. It is made from cod liver, and the liver tends to accumulate various toxins in high doses. In addition, when eating cod liver, there is a high probability of an overdose of vitamins A and D. For people who eat vegetarian food, flaxseed oil is a good replacement for fish oil.

Food supplements that are valuable sources of polyunsaturated fatty acids:

• Pollen.
• Sprouted wheat.
• Brewer's yeast.
• Aspen and borage oils (they can be found in pharmacies in capsule form).
• Soy lecithins.

In addition to some oils

The table provides data on the critical temperatures of some oils (in degrees Celsius), at which they decompose and release carcinogenic toxic substances that primarily affect the liver.

Oils sensitive to light and heat

• Walnut oil.
• Pumpkin.
• Linen.

Vitamin content tableE

Oils	mg per 100g oil
From wheat sprouts	300
From walnuts	170
Soy	94
Corn	28
Olive	15

Palm oil is a solid mass that contains almost 50% saturated acids. The oil is obtained without heating, mechanically, from the pulp of the oil palm fruit. Unlike margarine, it is obtained with a solid consistency without hydrogenation. Contains vitamin E. Often used instead of margarine or butter in baking. In large quantities it is harmful to health.

It is better not to eat coconut oil. It contains too many fatty acids. However, many people, especially those living in areas where coconut oil is produced, consider it a literal panacea for all ills. This is one of the oldest types of oils extracted by people. It is extracted from compressed dried coconut fruits. On the other hand, the good thing about coconut oil is that the saturated fat it contains has a completely different structure than the saturated fat used in fast food. That is why there is still debate about whether this oil is harmful or not.

Butter is, on the one hand, an excellent source of vitamins A and D, and on the other hand, cholesterol. But for small children, a small amount of butter will be beneficial, because when the body is actively growing, it requires saturated fats for harmonious and complete brain development.

What you should definitely know about butter: it absolutely does not tolerate heating above 120°. This means that you cannot fry food on it. Upon contact with the hot surface of the frying pan, the oil immediately begins to release carcinogenic substances that affect the intestines and stomach.

Margarine is an intermediate product between vegetable oil and butter. It was created as a substitute for butter. The composition of margarines may vary from one manufacturer to another. Some are enriched with wheat germ oil, while others contain only saturated fatty acids or are hydrogenated.

If you carry out a minimum of processing, that is, do not hydrogenate margarine, then some vitamins are retained in it. But it must be remembered that the hardness of margarine depends on the amount of palm and coconut oils added to it. Therefore, those who are prone to cardiovascular diseases are not recommended to use margarine.

Paraffin oil is a petroleum derivative and should be avoided. At food use paraffin oil absorption deteriorates fat-soluble vitamins. Moreover, when oil is excreted from the intestines, it binds to already dissolved vitamins and comes out along with them.

Functions of fats

Lipids in our body perform energy and plastic functions. Unsaturated fatty acids are essential because not all of them are synthesized in the body. They are precursors of prostaglandins. Prostaglandins are hormones that maintain the liquid state of cellular lipids, and also prevent the development of atherosclerotic plaques and prevent cholesterol and other lipids from sticking to the walls of blood vessels.

Phospholipids are the fundamental structures of most cell membranes. They are part of the white and gray matter of nervous tissue.

Fats by their nature are excellent solvents. Those substances that do not dissolve in water are highly soluble in fats. Most of the fat accumulates in adipose tissue cells, which are fat depots. Depot can account for up to 30% of body weight. The function of adipose tissue is to fix neurovascular bundles and internal organs. Fat is a thermal insulator that retains heat, particularly in childhood. Lipid metabolism is closely interconnected with protein and carbohydrate metabolism. When excess carbohydrates enter the body, they can turn into fats. In unfavorable conditions for the body, during fasting, fats turn back into carbohydrates.

The energy function is that lipids, of all nutrients, provide the body with the greatest amount of energy. It has been proven that the oxidation of 1 gram of fat releases 9.3 kilocalories of heat, which is twice as much as the oxidation of 1 gram of proteins or carbohydrates. The oxidation of 1 g of proteins and carbohydrates releases 4.1 kcal of heat.

Food fats

Triacylglycerols predominate among them. There are vegetable and animal fats, and vegetable fats are more complete because they contain much more unsaturated acids. A small amount of free fatty acids is also ingested with food. Normally, up to 40% of all calories consumed by our body come from lipids.

Absorption and digestion of fats

Digestion of fats is a process of enzymatic hydrolysis, which occurs in the small intestine and duodenum under the influence of enzyme substances found in the juices of the pancreas and intestinal glands.

In order for fats to be digested, the body must produce bile. It contains detergents (or bile acids) that emulsify lipids so that enzymes can break them down better. Products that are formed as a result of digestive hydrolysis - fatty acids, bile acids and glycerol - are absorbed from the intestinal cavity into the mucosal cells. In these cells, fat is resynthesized again and forms special particles called “chylomicrons”, which are sent to the lymph and lymphatic vessels, and then enter the blood through the lymph. In this case, only a small part of the fatty acids formed during the hydrolysis process, which have a relatively short carbon chain (in particular, these are the hydrolysis products of dairy fats) are absorbed and enter the blood of the portal vein, and then into the liver.

The role of the liver in lipid metabolism

The liver is responsible for the processes of mobilization, processing and biosynthesis of lipids. Short chain fatty acids combined with bile acids come from digestive tract through the portal vein with blood flow to the liver. These fatty acids do not participate in the processes of lipid synthesis and are oxidized with the assistance of liver enzyme systems. In adults, they generally do not play an important role in metabolism. The only exception is children; their diet contains the most fat from milk.

Other lipids enter through the hepatic artery as lipoproteins or chylomicrons. They are oxidized in the liver, as in other tissues. Most of the lipids, except for a few unsaturated ones, are newly synthesized in the body. Those of them that are not synthesized must be ingested along with food products. The overall process of fatty acid biosynthesis is called “lipogenesis”, and it is the liver that is most intensively involved in this process.

Enzymatic processes of transformation of phospholipids and cholesterol are carried out in the liver. The synthesis of phospholipids ensures the renewal of the structural units of its cell membranes in the liver.

Blood lipids

Blood lipids are called lipoproteins. They are associated with different protein fractions of the blood. Their own fractions during centrifugation are separated according to their relative density.

The first fraction is called "chylomicrons"; they consist of a thin protein shell and fats. The second fraction is lipoproteins with very low density. They contain a large amount of phospholipids. The third fraction is lipoproteins, containing a lot of cholesterol. The fourth fraction is high-density lipoproteins; they contain the most phospholipids. The fifth fraction is lipoproteins with high density and low content.

The function of lipoproteins in the blood is to transport lipids. Chylomicrons are synthesized in the intestinal mucous cells and carry fat that has been resynthesized from the products of fatty hydrolysis. Chylomicron fats are supplied, in particular, to adipose tissue and liver. Cells of all body tissues can consume chylomicron fatty acids if they have the necessary enzymes.

Very low density lipoproteins transport exclusively fats that are synthesized in the liver. These lipids are consumed, as a rule, by adipose tissue, although they can also be used by other cells. Fatty acids of high-density lipoproteins are products of the enzymatic breakdown of fat contained in adipose tissue. This faction has a kind of mobility. For example, during a fast, up to 70% of the body’s total energy expenditure is covered by fatty acids from this particular fraction. Phospholipids and cholesterol of high- and low-density lipoprotein fractions are a source of exchange with their corresponding components of cell membranes, with which these lipoproteins can interact.

Transformation of lipids in tissues
In tissues, lipids are broken down under the influence of various lipases, and the resulting fatty acids are added to other formations: phospholipids, cholesterol esters, etc.; or they are oxidized to final products. Oxidation processes occur in several ways. One part of fatty acids during oxidative processes in the liver produces acetone. In severe diabetes mellitus, lipoid nephrosis and some other diseases, the amount of acetone bodies in the blood increases sharply.

Regulation of fat metabolism

The regulation of lipid metabolism is carried out through a rather complex neurohumoral pathway, with the mechanisms predominating in it humoral regulation. If the functions of the gonads, pituitary gland, thyroid gland decrease, the processes of fat biosynthesis increase. The saddest thing is that not only the synthesis of lipids increases, but also their deposition in adipose tissue, and this leads to obesity.

Insulin is a hormone of the pancreas and is involved in the regulation of lipid metabolism. Since there is a cross-possibility of transformation of carbohydrates into fats, and then fats into carbohydrates, with insulin deficiency, the processes of carbohydrate synthesis are enhanced, which is accompanied by an acceleration of lipid breakdown processes, during which intermediate metabolic products are formed that are used for the biosynthesis of carbohydrates.

Phospholipids are close in structure to triacylglycerols, only their molecules contain phosphorus-containing groups. Steroids are derivatives of cholesterol and have a different structure. Lipids can also include a large group of fat-soluble substances, which includes vitamins A, D, K, E. Lipids are needed not only to create the lining of our body - they are necessary for hormones, for brain development, for blood vessels and nerves, for the heart. It is known that lipids make up 60% of the brain.

Disturbance of normal blood lipid concentrations

If there are abnormally elevated levels of lipids in the blood, then this pathological condition called hyperlipemia. With hypothyroidism, nephrosis, diabetes and disorders, doctors are faced with a secondary form of hyperlipemia. These diseases cause high levels of cholesterol and triglycerides. Primary hyperlipemia is a fairly rare hereditary pathology that contributes to the development of arteriosclerosis and coronary disease.


During hypoglycemia, fasting, after injections of growth hormone, adrenaline, the amount of free fatty acids in the body sharply increases and mobilization of previously deposited fat begins. This form of the disease is called mobilization hyperlipemia.

With hypercholesterolemia in the blood serum there is a high level of cholesterol and moderate levels of fatty acids. When interviewing close relatives, their medical history will necessarily reveal cases of early atherosclerosis. Hypercholesterolemia, even at an early age, can contribute to the development of myocardial infarction. Usually, external symptoms not visible. When a disease is detected, treatment is carried out with diet therapy. Its essence is to replace saturated acids with unsaturated acids. Correct diet correction significantly reduces the likelihood of developing pathologies of the vascular system.

With dyslipidemia, the balance in the blood is disturbed various types lipids. In particular, the main lipids contained in the blood are cholesterol and triglycerides in different proportions. It is the imbalance that leads to the development of diseases.
High levels of low-density lipids in the blood, as well as low level high-density cholesterol are serious risk factors for cardiovascular complications in patients with diagnosed diabetes mellitus second type. Abnormal levels of lipoproteins in in this case may result from improper glycemic control.

Dyslipidemia is considered the main cause of the development of atherosclerotic changes.

Factors influencing the development of dyslipidemia

Most significant reasons The formation of dyslipidemia is a genetic disorder of lipid metabolism. They consist of mutations in the genes responsible for the synthesis of apolipoproteins - the components of lipoproteins.

The second important factor is healthy/unhealthy lifestyle. Under unfavorable circumstances, lack of physical activity, and drinking alcohol, lipid metabolism is disrupted. Obesity is directly related to increased triglyceride levels and impaired cholesterol concentrations.

Another factor in the development of dyslipidemia is psychoemotional stress, which through neuroendocrine stimulation contributes to lipid metabolism disorders. Neuroendocrine stimulation refers to increased activity of the autonomic nervous system.

The clinical classification of types of dyslipidemia involves dividing them into so-called primary and secondary. Among the primary ones, we can distinguish polygenic (acquired during life, but due to hereditary disposition), and monogenic (genetically determined family diseases).

The cause of the secondary form of the disease can be: alcohol abuse, insufficient kidney function, diabetes, cirrhosis, hyperthyroidism, medications that give side effects (antiretroviral drugs, progestins, estrogens, glucocorticosteroids).

Diagnostic methods used to diagnose dyslipidemia include determining lipoprotein levels (high and low density), total cholesterol, and triglycerides. During the daily cycle, even completely healthy people experience fluctuations in cholesterol levels of about 10%; and fluctuations in triglyceride levels - up to 25%. To determine these indicators, blood donated on an empty stomach is centrifuged.

It is recommended to determine the lipid profile once every five years. At the same time, it is desirable to identify other potential risk factors for the development of cardiovascular pathologies (smoking, diabetes mellitus, a history of ischemia in close relatives).

Atherosclerosis

The main factor in the appearance of ischemia is the formation of many small atherosclerotic plaques, gradually increasing in the lumens of the coronary arteries and narrowing the lumen of these vessels. In the early stages of the disease, plaques do not impair blood flow, and the process does not manifest itself clinically. The gradual growth of the plaque and the simultaneous narrowing of the vessel duct can provoke the manifestation of signs of ischemia.
First, they will begin to appear during intense physical stress, when the myocardium requires more oxygen and this need cannot be met by an increase in coronary blood flow.

The clinical manifestation of the ischemic state of the myocardium is a sharp attack of angina. It is accompanied by such phenomena as pain and a feeling of constriction behind the sternum. The attack passes as soon as the stress of an emotional or physical nature stops.

Doctors consider lipid metabolism disorders to be the main (but not the only main) cause of ischemia, but besides this, smoking, obesity, carbohydrate metabolism disorders and genetic predisposition are significant factors. Cholesterol levels directly affect the occurrence of complications of heart disease.

Treatment of this disease is to normalize cholesterol levels. To achieve this, diet correction alone is not enough. It is also necessary to combat other risk factors for development: lose weight, increase physical activity, quit smoking. Nutrition correction involves not only reducing the total calorie content of food, but also replacing animal fats with vegetable fats in the diet: reducing
consumption of animal fats and a simultaneous increase in consumption of vegetable fats and fiber. We must remember that a significant part of the cholesterol in our body does not come with food, but is formed in the liver. Therefore, diet is not a panacea.

Used to lower cholesterol levels medications- nicotinic acid, estrogen, dextrothyroxine. Of these drugs, it is most effective against ischemia a nicotinic acid, however, its use is limited due to associated side effects. The same applies to other medications.

In the 80s of the last century, know-how began to be used in lipid-lowering therapy - drugs from the group of statins. Currently on pharmaceutical market There are 6 drugs available that belong to this group. Pravastatin and lovastatin are drugs based on fungal waste products. Rosuvastatin, atorvastatin, fluvastatin are synthetic drugs, and simvastatin is semi-synthetic.

These drugs help reduce low-density lipoprotein levels, reduce total cholesterol, and to a lesser extent, triglycerides. Several studies have also shown a reduction in overall mortality among ischemic patients.

Cardiosclerosis

This disease is a complication of atherosclerosis and consists of replacement of the myocardium with connective tissue. Connective tissue is not elastic, unlike the myocardium; accordingly, the elasticity of the entire organ on which the inelastic “patch” appears suffers, and the heart valves become deformed.

Cardiosclerosis (or myocardiosclerosis) is a logical consequence of an untreated disease: myocarditis, atherosclerosis, rheumatism. Acute development This disease occurs with myocardial infarction and coronary artery disease. When atherosclerotic plaques appear throughout the coronary arteries in the heart, the blood supply to the myocardium suffers, and it lacks oxygen carried through the bloodstream.

The acute form of ischemic disease is myocardial infarction. So the wrong way of life, unbalanced diet and smoking can become an implicit cause of a heart attack, and acute psycho-emotional stress, against the background of which a heart attack appears, is a visible, but far from the main reason.

Besides acute form, they also distinguish chronic. It is manifested by regularly occurring attacks of angina (that is, chest pain). You can relieve pain during an attack with nitroglycerin.

The body is designed in such a way that it tries to decompensate for any violation. Connective tissue scars prevent the heart from elastically stretching and contracting. Gradually, the heart adapts to the scars and simply increases in size, which leads to disruption of blood circulation through the vessels, disruption of muscle contractility, and expansion of the cardiac cavities. All this together causes insufficiency of heart function.

Cardiosclerosis is complicated by disturbances in heart rhythm (extrasystole, arrhythmia), protrusion of a fragment of the heart wall (aneurysm). The danger of an aneurysm is that the slightest tension can cause it to rupture, which leads to instant death.

Diagnosis of the disease is carried out using an electrocardiogram and ultrasound of the heart.

Treatment consists of the following: identifying and treating exactly the disease that was main reason development of cardiosclerosis; compliance with bed rest if the disease has led to myocardial infarction (at rest, scarring and healing occurs without the formation of a dangerous aneurysm); normalization of rhythm; stimulation of metabolic processes in the heart muscle, limitation of any stress; maintaining a properly balanced dietary nutrition, in particular, reducing the amount of lipids in the diet.

The diet has a good anti-allergic and anti-inflammatory effect, and is also considered an excellent preventive measure for the prevention of heart disease.

The basic rule of nutrition is moderation in the amount of food. It is also useful to lose extra pounds, which put a strain on the heart. The selection of food products should be carried out from the point of view of their value as energy and plastic materials for the heart. It is imperative to exclude spicy, sweet, fatty, and salty foods from food. Use alcoholic drinks Contraindicated for patients with vascular disorders. Food must be enriched minerals and vitamins. Fish, boiled meat, vegetables, fruits, dairy products should be the basis of the diet.

Thank you

The site provides background information for informational purposes only. Diagnosis and treatment of diseases must be carried out under the supervision of a specialist. All drugs have contraindications. Consultation with a specialist is required!

What kind of substances are lipids?

Lipids represent one of the groups of organic compounds having great value for living organisms. According to their chemical structure, all lipids are divided into simple and complex. Simple lipid molecule consists of alcohol and bile acids, while complex lipids also contain other atoms or compounds.

In general, lipids are of great importance to humans. These substances are included in a significant part of food products, are used in medicine and pharmacy, and play an important role in many industries. In a living organism, lipids in one form or another are part of all cells. From a nutritional point of view, it is a very important source of energy.

What is the difference between lipids and fats?

Basically, the term "lipids" comes from a Greek root meaning "fat", but there are still some differences between these definitions. Lipids are a larger group of substances, while fats refer to only certain types of lipids. A synonym for “fats” are “triglycerides,” which are obtained from a combination of glycerol alcohol and carboxylic acids. Both lipids in general and triglycerides in particular play a significant role in biological processes.

Lipids in the human body

Lipids are part of almost all tissues of the body. Their molecules are present in any living cell, and without these substances life is simply impossible. There are many different lipids found in the human body. Each type or class of these compounds has its own functions. Many biological processes depend on the normal supply and formation of lipids.

From a biochemical point of view, lipids take part in the following important processes:

• energy production by the body;

• cell division;
• transmission of nerve impulses;
• formation of blood components, hormones and other important substances;
• protection and fixation of some internal organs;
• cell division, respiration, etc.

Thus lipids are vital chemical compounds. A significant portion of these substances enters the body with food. After this, the structural components of lipids are absorbed by the body, and the cells produce new lipid molecules.

Biological role of lipids in a living cell

Lipid molecules perform a huge number of functions not only on the scale of the entire organism, but also in each living cell individually. In essence, a cell is a structural unit of a living organism. It is where assimilation and synthesis occurs ( education) certain substances. Some of these substances go to maintaining the life of the cell itself, some to cell division, and some to the needs of other cells and tissues.

In a living organism, lipids perform the following functions:

• energy;
• reserve;
• structural;
• transport;
• enzymatic;
• storing;
• signal;
• regulatory

Energy function

The energy function of lipids is reduced to their breakdown in the body, during which a large amount of energy is released. Living cells need this energy to maintain various processes ( respiration, growth, division, synthesis of new substances). Lipids enter the cell with blood flow and are deposited inside ( in the cytoplasm) in the form of small drops of fat. If necessary, these molecules are broken down and the cell receives energy.

Reserve ( storing) function

The reserve function is closely related to the energy function. In the form of fats inside cells, energy can be stored “in reserve” and released as needed. Special cells – adipocytes – are responsible for the accumulation of fats. Most of their volume is occupied by a large drop of fat. It is adipocytes that make up adipose tissue in the body. The largest reserves of adipose tissue are located in the subcutaneous fat, the greater and lesser omentum ( V abdominal cavity ). During prolonged fasting, adipose tissue gradually breaks down, as lipid reserves are used to obtain energy.

Also, adipose tissue deposited in subcutaneous fat provides thermal insulation. Tissues rich in lipids are generally poorer conductors of heat. This allows the body to maintain a constant body temperature and not cool down or overheat so quickly under different environmental conditions.

Structural and barrier functions ( membrane lipids)

Lipids play a huge role in the structure of living cells. In the human body, these substances form a special double layer that forms the cell wall. Thereby living cell can perform its functions and regulate metabolism with the external environment. Lipids that form the cell membrane also help maintain the shape of the cell.

Why do lipid monomers form a double layer ( bilayer)?

Monomers are called chemical substances (in this case – molecules), which are capable of combining to form more complex compounds. The cell wall consists of a double layer ( bilayer) lipids. Each molecule that forms this wall has two parts - hydrophobic ( not in contact with water) and hydrophilic ( in contact with water). The double layer is obtained due to the fact that the lipid molecules are deployed with hydrophilic parts inside and outside the cell. The hydrophobic parts practically touch, as they are located between the two layers. Other molecules may also be located in the depth of the lipid bilayer ( proteins, carbohydrates, complex molecular structures), which regulate the passage of substances through the cell wall.

Transport function

The transport function of lipids is of secondary importance in the body. Only some connections do this. For example, lipoproteins, consisting of lipids and proteins, transport certain substances in the blood from one organ to another. However, this function is rarely isolated, without considering it to be the main one for these substances.

Enzymatic function

In principle, lipids are not part of the enzymes involved in the breakdown of other substances. However, without lipids, organ cells will not be able to synthesize enzymes, the end product of vital activity. In addition, some lipids play a significant role in the absorption of dietary fats. Bile contains significant amounts of phospholipids and cholesterol. They neutralize excess pancreatic enzymes and prevent them from damaging intestinal cells. Dissolution also occurs in bile ( emulsification) exogenous lipids coming from food. Thus, lipids play a huge role in digestion and help in the work of other enzymes, although they are not enzymes themselves.

Signal function

Some complex lipids perform a signaling function in the body. It consists of maintaining various processes. For example, glycolipids in nerve cells take part in the transmission of nerve impulses from one nerve cell to another. In addition, signals within the cell itself are of great importance. She needs to “recognize” substances entering the blood in order to transport them inside.

Regulatory function

The regulatory function of lipids in the body is secondary. The lipids themselves in the blood have little effect on the course of various processes. However, they are part of other substances that are of great importance in the regulation of these processes. First of all, these are steroid hormones ( adrenal hormones and sex hormones). They play an important role in metabolism, growth and development of the body, reproductive function, and affect the work immune system. Lipids are also part of prostaglandins. These substances are produced during inflammatory processes and affect certain processes in the nervous system ( for example, pain perception).

Thus, lipids themselves do not perform a regulatory function, but their deficiency can affect many processes in the body.

Biochemistry of lipids and their relationship with other substances ( proteins, carbohydrates, ATP, nucleic acids, amino acids, steroids)

Lipid metabolism is closely related to the metabolism of other substances in the body. First of all, this connection can be traced in human nutrition. Any food consists of proteins, carbohydrates and lipids, which must enter the body in certain proportions. In this case, a person will receive both enough energy and enough structural elements. Otherwise ( for example, with a lack of lipids) proteins and carbohydrates will be broken down to produce energy.

Also, lipids are, to one degree or another, associated with the metabolism of the following substances:

• Adenosine triphosphoric acid ( ATP). ATP is a unique unit of energy inside a cell. When lipids are broken down, part of the energy goes into the production of ATP molecules, and these molecules take part in all intracellular processes ( transport of substances, cell division, neutralization of toxins, etc.).
• Nucleic acids. Nucleic acids are structural elements DNA is found in the nuclei of living cells. The energy generated during the breakdown of fats is partially used for cell division. During division, new DNA chains are formed from nucleic acids.
• Amino acids. Amino acids are structural components of proteins. In combination with lipids, they form complex complexes, lipoproteins, responsible for the transport of substances in the body.
• Steroids. Steroids are a type of hormone that contains significant amounts of lipids. If lipids from food are poorly absorbed, the patient may experience problems with the endocrine system.

Thus, lipid metabolism in the body in any case must be considered in its entirety, from the point of view of its relationship with other substances.

Digestion and absorption of lipids ( metabolism, metabolism)

Digestion and absorption of lipids is the first stage in the metabolism of these substances. The main part of lipids enters the body with food. In the oral cavity, food is crushed and mixed with saliva. Next, the lump enters the stomach, where the chemical bonds are partially destroyed by hydrochloric acid. Also, some chemical bonds in lipids are destroyed by the enzyme lipase contained in saliva.

Lipids are insoluble in water, so they are not immediately broken down by enzymes in the duodenum. First, the so-called emulsification of fats occurs. After this, the chemical bonds are broken down by lipase coming from the pancreas. In principle, each type of lipid now has its own enzyme responsible for the breakdown and absorption of this substance. For example, phospholipase breaks down phospholipids, cholesterol esterase breaks down cholesterol compounds, etc. All these enzymes are contained in varying quantities in pancreatic juice.

Cleaved lipid fragments are individually absorbed by cells small intestine. In general, the digestion of fats is a very difficult process, which is regulated by many hormones and hormone-like substances.

What is lipid emulsification?

Emulsification is the incomplete dissolution of fatty substances in water. In a bolus of food entering duodenum, fats are contained in the form of large drops. This prevents them from interacting with enzymes. During the emulsification process, large fat droplets are “crushed” into smaller droplets. As a result, the contact area between fat droplets and surrounding water-soluble substances increases, and lipid breakdown becomes possible.

The process of emulsification of lipids in the digestive system takes place in several stages:

• At the first stage, the liver produces bile, which will emulsify fats. It contains salts of cholesterol and phospholipids, which interact with lipids and contribute to their “crushing” into small droplets.
• Bile secreted from the liver accumulates in the gallbladder. Here it is concentrated and released as needed.
• When consuming fatty foods, a signal is sent to the smooth muscles of the gallbladder to contract. As a result, a portion of bile is released through the bile ducts into the duodenum.
• In the duodenum, fats are actually emulsified and interact with pancreatic enzymes. Contractions in the walls of the small intestine facilitate this process by “mixing” the contents.

Some people may have trouble absorbing fat after having their gallbladder removed. Bile enters the duodenum continuously, directly from the liver, and is not enough to emulsify the entire volume of lipids if too much is eaten.

Enzymes for lipid breakdown

To digest each substance, the body has its own enzymes. Their task is to break chemical bonds between molecules ( or between atoms in molecules), to useful material could be normally absorbed by the body. Different enzymes are responsible for breaking down different lipids. Most of them are contained in the juice secreted by the pancreas.

The following groups of enzymes are responsible for the breakdown of lipids:

• lipases;
• phospholipases;
• cholesterol esterase, etc.

What vitamins and hormones are involved in the regulation of lipid levels?

The levels of most lipids in human blood are relatively constant. It can fluctuate within certain limits. This depends on the biological processes occurring in the body itself, and on a number of external factors. Regulation of blood lipid levels is a complex biological process in which many different organs and substances are involved.

The following substances play the greatest role in the absorption and maintenance of constant lipid levels:

• Enzymes. A number of pancreatic enzymes take part in the breakdown of lipids entering the body with food. With a lack of these enzymes, the level of lipids in the blood may decrease, since these substances simply will not be absorbed in the intestines.
• Bile acids and their salts. Bile contains bile acids and a number of their compounds, which contribute to the emulsification of lipids. Without these substances, normal absorption of lipids is also impossible.
• Vitamins. Vitamins have a complex strengthening effect on the body and also directly or indirectly affect lipid metabolism. For example, with a lack of vitamin A, cell regeneration in the mucous membranes deteriorates, and the digestion of substances in the intestines also slows down.
• Intracellular enzymes. The intestinal epithelial cells contain enzymes that, after absorption of fatty acids, convert them into transport forms and send them into the bloodstream.
• Hormones. A number of hormones affect metabolism in general. For example, high insulin levels can greatly affect blood lipid levels. That is why some standards have been revised for patients with diabetes. Thyroid hormones, glucocorticoid hormones, or norepinephrine can stimulate the breakdown of fat tissue to release energy.

Thus, maintaining normal levels of lipids in the blood is a very complex process, which is directly or indirectly influenced by various hormones, vitamins and other substances. During the diagnostic process, the doctor needs to determine at what stage this process was disrupted.

Biosynthesis ( education) and hydrolysis ( decay) lipids in the body ( anabolism and catabolism)

Metabolism is the totality of metabolic processes in the body. All metabolic processes can be divided into catabolic and anabolic. Catabolic processes include the breakdown and breakdown of substances. In relation to lipids, this is characterized by their hydrolysis ( disintegrating into more simple substances ) in the gastrointestinal tract. Anabolism combines biochemical reactions aimed at the formation of new, more complex substances.

Lipid biosynthesis occurs in the following tissues and cells:

• Intestinal epithelial cells. Absorption of fatty acids, cholesterol and other lipids occurs in the intestinal wall. Immediately after this, new transport forms of lipids are formed in these same cells, which enter the venous blood and are sent to the liver.
• Liver cells. In liver cells, some of the transport forms of lipids will disintegrate, and new substances are synthesized from them. For example, cholesterol and phospholipid compounds are formed here, which are then excreted in bile and contribute to normal digestion.
• Cells of other organs. Some lipids travel with the blood to other organs and tissues. Depending on the cell type, lipids are converted into a specific type of compound. All cells, one way or another, synthesize lipids to form the cell wall ( lipid bilayer). In the adrenal glands and gonads, steroid hormones are synthesized from some lipids.

The combination of the above processes constitutes lipid metabolism in the human body.

Resynthesis of lipids in the liver and other organs

Resynthesis is the process of formation of certain substances from simpler ones that were absorbed earlier. In the body, this process occurs in the internal environment of some cells. Resynthesis is necessary so that tissues and organs receive all the necessary types of lipids, and not just those consumed with food. Resynthesized lipids are called endogenous. The body spends energy on their formation.

At the first stage, lipid resynthesis occurs in the intestinal walls. Here, fatty acids ingested from food are converted into transport forms that are transported through the blood to the liver and other organs. Part of the resynthesized lipids will be delivered to the tissues; from the other part, substances necessary for life will be formed ( lipoproteins, bile, hormones, etc.), the excess is converted into adipose tissue and stored “in reserve.”

Are lipids part of the brain?

Lipids are a very important component nerve cells not only in the brain, but throughout the entire nervous system. As you know, nerve cells control various processes in the body through the transmission of nerve impulses. At the same time, everything nerve pathways“isolated” from each other so that the impulse comes to certain cells and does not affect other nerve pathways. This “isolation” is possible thanks to the myelin sheath of nerve cells. Myelin, which prevents the chaotic propagation of impulses, consists of approximately 75% lipids. As in cell membranes, here they form a double layer ( bilayer), which is wrapped several times around the nerve cell.

The myelin sheath in the nervous system contains the following lipids:

• phospholipids;
• cholesterol;
• galactolipids;
• glycolipids.

Some congenital lipid disorders may cause neurological problems. This is explained precisely by the thinning or interruption of the myelin sheath.

Lipid hormones

Lipids play an important structural role, including being present in the structure of many hormones. Hormones that contain fatty acids are called steroid hormones. In the body they are produced by the gonads and adrenal glands. Some of them are also present in adipose tissue cells. Steroid hormones take part in the regulation of many vital processes. Their imbalance can affect body weight, the ability to conceive a child, the development of any inflammatory processes, and the functioning of the immune system. The key to normal production of steroid hormones is a balanced intake of lipids.

Lipids are part of the following vital hormones:

• corticosteroids ( cortisol, aldosterone, hydrocortisone, etc.);
• male sex hormones - androgens ( androstenedione, dihydrotestosterone, etc.);
• female sex hormones - estrogens ( estriol, estradiol, etc.).

Thus, a lack of certain fatty acids in food can seriously affect the functioning of the endocrine system.

The role of lipids for skin and hair

Lipids are of great importance for the health of the skin and its appendages ( hair and nails). The skin contains so-called sebaceous glands, which release a certain amount of fat-rich secretion to the surface. This substance performs many useful functions.

Lipids are important for hair and skin for the following reasons:

• a significant part of the hair substance consists of complex lipids;
• skin cells change rapidly, and lipids are important as an energy resource;
• secret ( secreted substance) sebaceous glands moisturizes the skin;
• Thanks to fats, the firmness, elasticity and smoothness of the skin is maintained;
• a small amount of lipids on the surface of the hair gives it a healthy shine;
• the lipid layer on the surface of the skin protects it from the aggressive effects of external factors ( cold, sun rays, microbes on the surface of the skin, etc.).

Lipids enter skin cells, as well as hair follicles, with the blood. Thus, proper nutrition ensures healthy skin and hair. The use of shampoos and creams containing lipids ( especially essential fatty acids) is also important because some of these substances will be absorbed from the surface of the cells.

Classification of lipids

In biology and chemistry, there are quite a few different classifications of lipids. The main one is chemical classification, according to which lipids are divided depending on their structure. From this point of view, all lipids can be divided into simple ones ( consisting only of oxygen, hydrogen and carbon atoms) and complex ( containing at least one atom of other elements). Each of these groups has corresponding subgroups. This classification is the most convenient, as it reflects not only chemical structure substances, but also partially determines the chemical properties.

Biology and medicine have their own additional classifications that use other criteria.

Exogenous and endogenous lipids

All lipids in the human body can be divided into two large groups - exogenous and endogenous. The first group includes all substances that enter the body from the external environment. Largest quantity exogenous lipids enter the body with food, but there are other routes. For example, when using various cosmetics or medications, the body can also receive a certain amount of lipids. Their action will be predominantly local.

After entering the body, all exogenous lipids are broken down and absorbed by living cells. Here, from their structural components, other lipid compounds that the body needs will be formed. These lipids, synthesized by one's own cells, are called endogenous. They may have a completely different structure and function, but they consist of the same “structural components” that entered the body with exogenous lipids. That is why, with a lack of certain types of fats in food, various diseases can develop. Some components of complex lipids cannot be synthesized by the body independently, which affects the course of certain biological processes.

Fatty acid

Fatty acids are a class of organic compounds that are a structural part of lipids. Depending on which fatty acids are included in the lipid, the properties of this substance may change. For example, triglycerides, the most important source of energy for the human body, are derivatives of the alcohol glycerol and several fatty acids.

In nature, fatty acids are found in a variety of substances - from oil to vegetable oils. They enter the human body mainly through food. Each acid is structural component for certain cells, enzymes or compounds. Once absorbed, the body converts it and uses it in various biological processes.

The most important sources of fatty acids for humans are:

• animal fats;
• vegetable fats;
• tropical oils ( citrus, palm, etc.);
• fats for the food industry ( margarine, etc.).

In the human body, fatty acids can be stored in adipose tissue as triglycerides or circulate in the blood. They are found in the blood both in free form and in the form of compounds ( various fractions of lipoproteins).

Saturated and unsaturated fatty acids

All fatty acids according to their chemical structure are divided into saturated and unsaturated. Saturated acids are less beneficial for the body, and some of them are even harmful. This is explained by the fact that there are no double bonds in the molecule of these substances. These are chemically stable compounds and are less easily absorbed by the body. Currently, the connection between some saturated fatty acids and the development of atherosclerosis has been proven.

Unsaturated fatty acids are divided into two large groups:

• Monounsaturated. These acids have one double bond in their structure and are therefore more active. It is believed that eating them can lower cholesterol levels and prevent the development of atherosclerosis. The greatest amount of monounsaturated fatty acids is found in a number of plants ( avocado, olives, pistachios, hazelnuts) and, accordingly, in oils obtained from these plants.
• Polyunsaturated. Polyunsaturated fatty acids have several double bonds in their structure. Distinctive feature of these substances is that the human body is not able to synthesize them. In other words, if the body does not receive polyunsaturated fatty acids from food, over time this will inevitably lead to certain disorders. Best sources These acids are seafood, soybean and flaxseed oil, sesame seeds, poppy seeds, wheat germ, etc.

Phospholipids

Phospholipids are complex lipids containing a phosphoric acid residue. These substances, along with cholesterol, are the main components of cell membranes. These substances also take part in the transport of other lipids in the body. From a medical point of view, phospholipids can also play a signaling role. For example, they are part of bile, as they promote emulsification ( dissolution) other fats. Depending on which substance is more in bile, cholesterol or phospholipids, you can determine the risk of developing cholelithiasis.

Glycerol and triglycerides

In terms of its chemical structure, glycerol is not a lipid, but it is an important structural component of triglycerides. This is a group of lipids that play a huge role in the human body. The most important function of these substances is to supply energy. Triglycerides that enter the body with food are broken down into glycerol and fatty acids. As a result, a very large amount of energy is released, which goes to work the muscles ( skeletal muscles, cardiac muscles, etc.).

Adipose tissue in the human body is represented mainly by triglycerides. Most of these substances, before being deposited in adipose tissue, undergo some chemical transformations in the liver.

Beta lipids

Beta lipids are sometimes called beta lipoproteins. The duality of the name is explained by differences in classifications. This is one of the fractions of lipoproteins in the body, which plays an important role in the development of certain pathologies. First of all, we are talking about atherosclerosis. Beta lipoproteins transport cholesterol from one cell to another, but due to the structural features of the molecules, this cholesterol often “gets stuck” in the walls of blood vessels, forming atherosclerotic plaques and preventing normal blood flow. Before use, you should consult a specialist.

Determination of blood lipid profile indicators is necessary for the diagnosis, treatment and prevention of cardiovascular diseases. The most important mechanism for the development of such a pathology is the formation of atherosclerotic plaques on the inner wall of blood vessels. Plaques are accumulations of fat-containing compounds (cholesterol and triglycerides) and fibrin. The higher the concentration of lipids in the blood, the probable occurrence atherosclerosis. Therefore, it is necessary to systematically take a blood test for lipids (lipidogram), this will help to promptly identify deviations in fat metabolism from the norm.

Lipidogram - a study that determines the level of lipids of various fractions

Atherosclerosis is dangerous due to the high probability of complications - stroke, myocardial infarction, gangrene lower limbs. These diseases often result in disability of the patient, and in some cases, death.

The role of lipids

Functions of lipids:

• Structural. Glycolipids, phospholipids, cholesterol are the most important components of cell membranes.
• Thermal insulation and protective. Excess fat is deposited in subcutaneous fat, reducing heat loss and protecting internal organs. If necessary, the lipid supply is used by the body to obtain energy and simple compounds.
• Regulatory. Cholesterol is necessary for the synthesis of adrenal steroid hormones, sex hormones, vitamin D, bile acids, is part of the myelin sheaths of the brain, is needed for normal functioning serotonin receptors.

Lipidogram

A lipidogram can be prescribed by a doctor both if an existing pathology is suspected and for preventive purposes, for example, during a medical examination. It includes several indicators that allow you to fully assess the state of fat metabolism in the body.

Lipid profile indicators:

• Total cholesterol (TC). This the most important indicator lipid spectrum blood, includes free cholesterol, as well as cholesterol contained in lipoproteins and associated with fatty acids. A significant portion of cholesterol is synthesized by the liver, intestines, and gonads; only 1/5 of the TC comes from food. With normally functioning mechanisms of lipid metabolism, a slight deficiency or excess of cholesterol supplied from food is compensated by an increase or decrease in its synthesis in the body. Therefore, hypercholesterolemia is most often caused not by excess cholesterol intake from foods, but by a failure of the fat metabolism process.
• High density lipoproteins (HDL). This indicator has an inverse relationship with the likelihood of developing atherosclerosis - an increased level of HDL is considered an anti-atherogenic factor. HDL transports cholesterol to the liver, where it is utilized. Women have higher HDL levels than men.
• Low density lipoproteins (LDL). LDL carries cholesterol from the liver to tissues, otherwise known as “bad” cholesterol. This is due to the fact that LDL is capable of forming atherosclerotic plaques, narrowing the lumen of blood vessels.

This is what an LDL particle looks like

• Very low density lipoproteins (VLDL). The main function of this group of particles, heterogeneous in size and composition, is the transport of triglycerides from the liver to tissues. A high concentration of VLDL in the blood leads to clouding of the serum (chylosis), and the possibility of the appearance of atherosclerotic plaques also increases, especially in patients with diabetes mellitus and kidney pathologies.
• Triglycerides (TG). Like cholesterol, triglycerides are transported through the bloodstream as part of lipoproteins. Therefore, an increase in the concentration of TG in the blood is always accompanied by an increase in cholesterol levels. Triglycerides are considered the main source of energy for cells.
• Atherogenic coefficient. It allows you to assess the risk of developing vascular pathology and is a kind of summary of the lipid profile. To determine the indicator, you need to know the value of TC and HDL.

Atherogenic coefficient = (TC - HDL)/HDL

Optimal blood lipid profile values

Floor	Indicator, mmol/l
	OH	HDL	LDL	VLDL	TG	CA
Male	3,21 — 6,32	0,78 — 1,63	1,71 — 4,27	0,26 — 1,4	0,5 — 2,81	2,2 — 3,5
Female	3,16 — 5,75	0,85 — 2,15	1,48 — 4,25		0,41 — 1,63

It should be taken into account that the value of the measured indicators may vary depending on the units of measurement and the analysis methodology. Normal values ​​also vary depending on the age of the patient; the above figures are averaged for persons 20 - 30 years old. The level of cholesterol and LDL in men after 30 years tends to increase. In women, indicators increase sharply with the onset of menopause, this is due to the cessation of the antiatherogenic activity of the ovaries. The interpretation of the lipid profile must be carried out by a specialist, taking into account the individual characteristics of the person.

A study of blood lipid levels can be prescribed by a doctor to diagnose dyslipidemia, assess the likelihood of developing atherosclerosis, in some chronic diseases (diabetes mellitus, kidney and liver diseases, thyroid gland), and also as a screening test for early detection persons with lipid profile deviations from the norm.

The doctor gives the patient a referral for a lipid profile

Preparing for the study

Lipid profile values ​​can fluctuate not only depending on the gender and age of the subject, but also on the impact of various external and internal factors on the body. To minimize the likelihood of an unreliable result, you must adhere to several rules:

1. You should donate blood strictly in the morning on an empty stomach; in the evening of the previous day, a light dietary dinner is recommended.
2. Do not smoke or drink alcohol the night before the test.
3. 2-3 days before donating blood, avoid stressful situations and intense physical activity.
4. Stop using all medications and dietary supplements except those that are vital.

Methodology

There are several methods laboratory evaluation lipid profile. IN medical laboratories analysis can be carried out manually or using automatic analyzers. The advantage of an automated measurement system is the minimal risk of erroneous results, the speed of obtaining analysis, high accuracy research.

Serum is required for analysis. venous blood patient. Blood is drawn into a vacuum tube using a syringe or vacutainer. To avoid clot formation, the blood tube should be inverted several times and then centrifuged to obtain serum. The sample can be stored in the refrigerator for 5 days.

Taking blood for lipid profile

Nowadays, blood lipids can be measured without leaving home. To do this, you need to purchase a portable biochemical analyzer that allows you to assess the level of total cholesterol in the blood or several indicators at once in a matter of minutes. For the test, a drop of capillary blood is needed; it is applied to the test strip. Test strip is saturated special composition, for each indicator it is different. The results are read automatically after inserting the strip into the device. Thanks to the small size of the analyzer and the ability to operate on batteries, it is convenient to use at home and take with you on a trip. Therefore, persons with a predisposition to cardiovascular diseases are recommended to have it at home.

Interpretation of results

The most ideal result of the analysis for the patient will be a laboratory conclusion that there are no deviations from the norm. In this case, a person need not fear for the condition of his circulatory system- the risk of atherosclerosis is practically absent.

Unfortunately, this is not always the case. Sometimes the doctor, after reviewing the laboratory data, makes a conclusion about the presence of hypercholesterolemia. What it is? Hypercholesterolemia is an increase in the concentration of total cholesterol in the blood above normal values, and there is a high risk of developing atherosclerosis and related diseases. This condition may be due to a number of reasons:

• Heredity. Science knows cases of familial hypercholesterolemia (FH), in such a situation the defective gene responsible for lipid metabolism is inherited. Patients experience constantly elevated levels of TC and LDL; the disease is especially severe in the homozygous form of FH. Such patients have an early onset of coronary artery disease (at the age of 5-10 years); in the absence of proper treatment, the prognosis is unfavorable and in most cases ends in death before reaching 30 years of age.
• Chronic diseases. Elevated cholesterol levels are observed in diabetes mellitus, hypothyroidism, kidney and liver pathologies, and are caused by lipid metabolism disorders due to these diseases.

For patients suffering from diabetes, it is important to constantly monitor cholesterol levels

• Poor nutrition. Long-term abuse of fast food, fatty, salty foods leads to obesity, and, as a rule, there is a deviation in lipid levels from the norm.
• Bad habits. Alcoholism and smoking lead to disruptions in the mechanism of fat metabolism, as a result of which lipid profile indicators increase.

With hypercholesterolemia, it is necessary to adhere to a diet with limited fat and salt, but in no case should you completely abandon all foods rich in cholesterol. Only mayonnaise, fast food and all products containing trans fats should be excluded from the diet. But eggs, cheese, meat, sour cream must be present on the table, you just need to choose products with a lower percentage of fat content. Also important in the diet is the presence of greens, vegetables, cereals, nuts, and seafood. The vitamins and minerals they contain perfectly help stabilize lipid metabolism.

An important condition for normalizing cholesterol is also giving up bad habits. Constant physical activity is also beneficial for the body.

In case if healthy image life in combination with diet did not lead to a decrease in cholesterol, it is necessary to prescribe appropriate drug treatment.

Drug treatment of hypercholesterolemia includes the prescription of statins

Sometimes specialists are faced with a decrease in cholesterol levels - hypocholesterolemia. Most often, this condition is caused by insufficient intake of cholesterol from food. Fat deficiency is especially dangerous for children; in such a situation, there will be a lag in physical and mental development; cholesterol is vital for a growing body. In adults, hypocholesteremia leads to disorders emotional state due to malfunctions of the nervous system, problems with reproductive function, decreased immunity, etc.

Changes in the blood lipid profile inevitably affect the functioning of the entire body, so it is important to systematically monitor fat metabolism indicators for timely treatment and prevention.

Lipids - what are they? Translated from Greek, the word "lipids" means "small particles of fat." They are groups of natural organic compounds of a broad nature, including fats themselves, as well as fat-like substances. They are part of all living cells without exception and are divided into simple and complex categories. Simple lipids contain alcohol and fatty acids, while complex lipids contain high-molecular components. Both are associated with biological membranes, have an effect on active enzymes, and also participate in the formation of nerve impulses that stimulate muscle contractions.

Fats and hydrophobia

One of them is the creation of the body’s energy reserve and ensuring the water-repellent properties of the skin, coupled with thermal insulation protection. Some fat-containing substances that do not have fatty acids are also classified as lipids, for example, terpenes. Lipids are not susceptible to exposure to an aqueous environment, but are easily dissolved in organic liquids such as chloroform, benzene, and acetone.

Lipids, the presentation of which is periodically held at international seminars in connection with new discoveries, are an inexhaustible topic for research and scientific research. The question "Lipids - what are they?" never loses its relevance. However, scientific progress does not stand still. IN Lately Several new fatty acids have been identified that are biosynthetically related to lipids. Classification of organic compounds can be difficult due to similarity in certain characteristics, but significant differences in other parameters. Most often created separate group, after which the overall picture of the harmonious interaction of related substances is restored.

Cell membranes

Lipids - what are they in terms of their functional purpose? First of all, they are an essential component of living cells and tissues of vertebrates. Most processes in the body occur with the participation of lipids; the formation of cell membranes, interconnection and exchange of signals in the intercellular environment cannot do without fatty acids.

Lipids - what are they if we consider them from the perspective of spontaneously occurring steroid hormones, phosphoinositides and prostaglandins? This is, first of all, the presence in the blood plasma of which, by definition, are individual components of lipid structures. Because of the latter, the body is forced to develop complex systems for their transportation. Fatty acids of lipids are mainly transported in complex with albumin, and lipoproteins, soluble in water, are transported in the usual manner.

Classification of lipids

Distribution of compounds having biological nature, by category - this is a process associated with some controversial issues. Lipids, due to their biochemical and structural properties, can be equally classified as different categories. The main classes of lipids include simple and complex compounds.

Simple ones include:

• Glycerides are esters of glycerin alcohol and fatty acids of the highest category.
• Waxes - ether of the highest fatty acid and 2-hydroxy alcohol.

Complex lipids:

• Phospholipid compounds - with the inclusion of nitrogenous components, glycerophospholipids, ophingolipids.
• Glycolipids - located in the outer biological layers of the body.
• Steroids are highly active substances of the animal spectrum.
• Complex fats - sterols, lipoproteins, sulfolipids, aminolipids, glycerol, hydrocarbons.

Operation

Lipid fats act as material for cell membranes. Participate in the transport of various substances around the periphery of the body. Fat layers based on lipid structures help protect the body from hypothermia. They have the function of energy accumulation “in reserve”.

Fat reserves are concentrated in the cytoplasm of cells in the form of droplets. Vertebrates, including humans, have special cells - adipocytes, which are capable of containing quite a lot of fat. The placement of fat accumulations in adipocytes occurs thanks to lipoid enzymes.

Biological functions

Fat is not only a reliable source of energy, it also has insulating properties, which biology contributes to. In this case, lipids allow you to achieve several useful functions, such as natural cooling of the body or, conversely, its thermal insulation. In the northern regions, different low temperatures, all animals accumulate fat, which is deposited evenly throughout the body, and thus a natural protective layer is created that performs the function of heat protection. This is especially important for large marine animals: whales, walruses, seals.

Animals living in hot countries also accumulate fat deposits, but they are not distributed throughout the body, but are concentrated in certain places. For example, in camels, fat accumulates in the humps, in desert animals - in thick, short tails. Nature carefully monitors the correct placement of both fat and water in living organisms.

Structural function of lipids

All processes associated with the life of the body are subject to certain laws. Phospholipids are the basis of the biological layer of cell membranes, and cholesterol regulates the fluidity of these membranes. Thus, most living cells are surrounded by plasma membranes with a lipid bilayer. This concentration is necessary for normal cellular activity. One biomembrane microparticle contains more than a million lipid molecules, which have dual characteristics: they are both hydrophobic and hydrophilic. As a rule, these mutually exclusive properties are of a non-equilibrium nature, and therefore their functional purpose looks quite logical. Lipids in the cell are an effective natural regulator. The hydrophobic layer usually dominates and protects the cell membrane from the penetration of harmful ions.

Glycerophospholipids, phosphatidylethanolamine, phosphatidylcholine, and cholesterol also contribute to cell impermeability. Other membrane lipids are located in tissue structures, these are sphingomyelin and sphingoglycolipid. Each substance performs a specific function.

Lipids in the human diet

Triglycerides are an effective source of energy. Meat and dairy products have acids. And fatty acids, but unsaturated, are found in nuts, sunflower and olive oil, seeds and corn grains. To prevent cholesterol levels from increasing in the body, it is recommended daily norm limit animal fats to 10 percent.

Lipids and carbohydrates

Many organisms of animal origin “store” fats at certain points, subcutaneous tissue, in the folds of the skin, and other places. The oxidation of lipids in such fatty deposits occurs slowly, and therefore the process of their transition to carbon dioxide and water allows you to get a significant amount of energy, almost twice as much as carbohydrates can provide. In addition, the hydrophobic properties of fats eliminate the need to use large amounts of water to promote hydration. The transition of fats into the energy phase occurs “dry”. However, fats act much more slowly in terms of energy release and are more suitable for hibernating animals. Lipids and carbohydrates seem to complement each other during the life of the body.