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The myth of cholesterol — the biggest fraud of the twentieth century
The whole truth about itNow is the moment when the reader does finally tell the truth about the biochemistry, metabolism and functions of cholesterol.
Cholesterol is often confused with fats. Unlike fat, cholesterol is not used by the body to produce calories and has no relation to obesity or to the cellulite (cellulite is pure myth, invented by cosmetologists, but it deserves a separate discussion).
Cholesterol — fat-like organic substance from the group of sterols of animal origin. Its molecular formula С27Н46О. From the chemical point of view, this unsaturated alcohol. Cholesterol has a complex heterocyclic steroid nucleus. The carbon skeleton of cholesterol consists of four rings: three rings contain 6 carbon atoms and one or 5 atoms. It departs from the long side chain (figure below). Molecules of cholesterol are hydrophobic. A characteristic chemical property — the ability to form molecular complexes with many salts, acids, amines, proteins etc. Most cholesterol in animal tissues is present in the form of esters of fatty acids.
Fifty nine million three hundred ninety eight thousand two hundred seventy one
By the way.:
In plants there is no cholesterol — no and no, so the inscription on the bottle of vegetable oil "contains no cholesterol" — very true. In plants, there are other sterols, known as phytosterols, molecular structure similar to steroid hormones. They are often added in cosmetics is prohibited for this purpose human hormones. Whether they act on the skin or only the mood of consumers is also a topic for another article.We speak of "cholesterol" — mean "atherosclerosis". We say "atherosclerosis" — mean "cholesterol". And is it true? In fact, the cholesterol would have to rank at least the vitamins! The normal functioning of a number of vital systems of the human body is not possible without cholesterol.
Cholesterol is absolutely essential as a building material for cell membranes during cell division. It is especially important for a growing child's body. Not one cell in our body can't do without him, as "cholesteric structure" is the basis of cell membranes, regulates their permeability and activity of membrane enzymes. The amount of cholesterol in the membrane to a certain extent depends on the strength of the cell, its ability to survive. It protects intracellular structures against the destructive action of free oxygen radicals that are formed during metabolism and under the influence of external factors.
Breast milk is rich in cholesterol. Infants and growing children need fat-rich and cholesterol products, including the full development of the brain and nervous system.
According to the data of radionuclide studies in the human body contains up to 350 grams of this substance: 90% in the tissues and 10% in the blood. About 20% of the total amount of cholesterol contained in the brain and spinal cord — it is a structural component of the myelin "insulation" of the nerves. In plasma it is in the form of esters with higher fatty acids and serves as a carrier during their transport.
In the liver from cholesterol synthesized bile acids are necessary for emulsification and absorption of fats in the small intestine. For this purpose goes 60-80% of the daily formed in the body of cholesterol.
Cholesterol is the "raw material" for the production of steroid hormones of the adrenal cortex (hydrocortisone and aldosterone), and both male and female sex hormones (estrogens and androgens). In men, the obsession with cholesterol-free foods can be dangerous for sexual activity, and women, very active in the fight against cholesterol, amenorrhea often occurs. Especially pointless adherence to a cholesterol diet of women of childbearing age, since menopause female sex hormones just do not allow the cholesterol to be deposited on the walls of blood vessels.
Seven million two hundred thirty thousand four hundred seventy seven
Close relatives: cholesterol, hormones and vitamin D (image source www.cbio.ru) Cholesterol — a fat-soluble precursor of vitamin D, necessary for calcium metabolism. This is especially important for bone, nervous system, insulin production, maintain muscle tone, mineral metabolism, the immune system and for normal growth and development of the child.
By the way.:
Vitamin D is formed in the skin by action of ultraviolet light. Its content in the food (even in such as fish liver, fatty fish, caviar, eggs, dairy fats). Hypovitaminosis D threatens miners, explorers and young children. Breastfed infants vitamin D deficiency is very common and leads to the development of rickets. The daily adult requirement of this vitamin is uncertain. The inhabitants of the far North in the polar night and babies in the winter to sunbathe under the ultraviolet lamp, and if it is not possible to take vitamin drops or tablets — as long as the doctor ordered: hypervitaminosis D — an unpleasant thing.Cholesterol is required for normal activity of serotonin receptors in the brain. Serotonin, a substance responsible for good mood. Low cholesterol is associated with depression, aggressive behavior and tendency to suicide. Particularly acute is manifested in the elderly. Elderly people with low cholesterol melancholy three times more often than their peers who have a cholesterol — article about it was published in the prestigious medical journal "the Lancet". Recently the American scientists have proved that those people who have managed every conceivable way to lower cholesterol, are more likely to have an accident resulting in death, committed suicide, become victims of violence.
Chemical signal by which glial cells of the brain induce neurons to form new synapses appeared to be cholesterol. Researchers from Boston University have shown that a decrease in the content of cholesterol in the blood may reduce intellectual abilities. (Neuroglia, from GK. neuron "once upon a time, the nerve" and glia "glue" cells in the brain and spinal cord, filling the space between neurons and brain capillaries. Serve to protect and support neurons, provides reactive properties of nervous tissue — scarring, participation in the reactions of inflammation, etc.)
As shown by the results obtained by scientists from Harvard University, a high content of cholesterol associated with a "good" high-density lipoproteins (HDL), by 30-40% reduces the risk of developing Alzheimer's compared to people of the same age group with average cholesterol levels. A lipoprotein is a complex of proteins (proteins), molecules which include fats (lipids) and what is "good" and "bad" lipoproteins, we will examine below.
Since cholesterol is so important for normal functioning of the body, entering it with food (exogenous cholesterol) is complemented by synthesis in cells of almost all organs and tissues (endogenous cholesterol). Especially a lot of it is produced by the liver (80%), in the wall of the small intestine (10%) and skin (5%). Measurements and calculations show that only one third of the necessary cholesterol our body gets from food, and two-thirds are produced by the cells of the body. Daily in the human body is synthesized from 0.7 to 1 g of cholesterol, two times more than the approximately 0.3–0.5 g, which come from food. A relatively small excess or deficiency of cholesterol in the diet, the body compensates for the change of the synthesis of cholesterol. About the consequences of a significant shortage we have already said. But the damage is moderately excessive and even normal receipt of cholesterol with food is highly exaggerated. But to prove it, you need to understand what happens to the cholesterol in the body.
Way cholesterol
Biochemist Konrad Bloch (he emigrated to the United States from Hitler's Germany) and his collaborators in 1942 showed that cholesterol synthesis begins with acetic acid, and unearthed main stages of cholesterol biosynthesis: acetate — cholesterol — fatty acids — sex hormones. Thanks to his discovery, it became clear that cholesterol is a necessary component of all body cells, and that all steroid substances in the human body are produced from cholesterol. In 1964 K. Bloch together with F. Linenum became a laureate of the Nobel prize in physiology or medicine for discoveries concerning the mechanisms and regulation of cholesterol metabolism and fatty acids. The main stages of cholesterol synthesis is shown in Fig.
Eleven million nine hundred seventy one thousand two hundred eighty four
The main stages of cholesterol synthesis At the first stage of this process from three molecules of acetate and coenzyme A is synthesized 3-hydroxy-3-methylglutaryl coenzyme a (HMG-COA). Next, effects of the enzyme HMG-COA reductase is formed mevalonova acid, which about 20 of the subsequent stages is transformed into cholesterol.
Despite the complexity and multistage of these processes, a key enzyme in determining the rate of synthesis of cholesterol is HMG-COA reductase. The work of this enzyme and inhibit the statins — widely promoted lipid-lowering (cholesterol lowering) drugs, which will be discussed later.
The mechanism of cholesterol homeostasis is complex. Intracellular cholesterol content is regulated by two mechanisms. The first of these controls the production of cholesterol by the negative feedback mechanism. The second mechanism of controlling the level of cholesterol in the cell is associated with the regulation of its transport across the cellular membrane from the intercellular space. This transport is carried out with the involvement of receptors of low-density lipoproteins (LDL).
In the exchange of cholesterol involve dozens of enzymes, and a mutation in each of their encoding genes can lead to the malfunction of the entire system. Known, for example, so-called family — inherited forms of hypercholesterolemia (excess cholesterol). These lipid disorders are associated with mutations of the genes encoding the receptor for low density lipoprotein. If the mutant gene is present in only one of the pairs of chromosomes, a so-called heterozygous form of hereditary hypercholesterolemia (in America and Europe, it occurs in one out of 500 people), if two mutant genes are homozygous (found in one person out of a million). In both cases suffer from the LDL receptors located on the surface of hepatocytes — liver cells. These receptors play an important role in the metabolism of cholesterol, as LDL is one of its vectors.
The cholesterol metabolism in hereditary familial hypercholesterolemia is a genetic disease inherited in dominant pattern and characterized by extremely high blood levels of LDL and accumulation of cholesterol in tissues — involved Michael brown and Joseph Goldstein. In 1985 they were awarded the Nobel prize in physiology and medicine for his outstanding discoveries concerning cholesterol metabolism and treatment of disorders of cholesterol in the blood.
It should be emphasized that today, studied not only the genes encoding the LDL receptors, but also genes encoding, for example, the protein part of lipoproteins, proteins A and B that play an important role in the ability of these molecules transfer cholesterol.
Incidentally, genes that control the synthesis of cholesterol in the human body, playing an important role in determining life expectancy. Mutation of one of the genes occur in 25% of older people and only have 8.6% of people under 30 years of age. In other words, they accumulate with age, that is trigger the development of senile changes.
Paradoxically, advances in mechanisms of biosynthesis and cholesterol metabolism is not something that ignore and hide from the public, but do not promote — in accordance with the social order. As information about the dangers of TRANS isomers of fatty acids, which are converted to vegetable fats in the production of margarine — a product of supposedly "diet" and "useful" and do not contain cholesterol. (TRANS-isomers of fatty acids and all the history of margarine is also a topic for a separate conversation.)
Doctors, the most advanced of the patients know that cholesterol from food is not associated with atherosclerosis — except in extreme cases like the Atkins diet, when the biochemistry of the body turned inside out because of the monstrous amounts of fat and severe lack of carbohydrates. But the main and mandatory medical recommendation for the prevention and treatment of atherosclerosis is to eliminate from the diet all fatty, and the eggs, brains and other cholesterol-rich foods and to replace animal fats for vegetable oil and margarine.
It is likely that you will recommend taking statins — the main and the miraculous (according to the developers and vendors) means "cholesterol". I wonder how the manufacturers of products and medications get doctors such doublethink? Am using only a single advertisement? published
P. S. And remember, only by changing their consumption — together we change the world! ©
Join us in Facebook , Vkontakte, Odnoklassniki
Source: cbio.ru/page/47/id/2127/
Cholesterol is often confused with fats. Unlike fat, cholesterol is not used by the body to produce calories and has no relation to obesity or to the cellulite (cellulite is pure myth, invented by cosmetologists, but it deserves a separate discussion).
Cholesterol — fat-like organic substance from the group of sterols of animal origin. Its molecular formula С27Н46О. From the chemical point of view, this unsaturated alcohol. Cholesterol has a complex heterocyclic steroid nucleus. The carbon skeleton of cholesterol consists of four rings: three rings contain 6 carbon atoms and one or 5 atoms. It departs from the long side chain (figure below). Molecules of cholesterol are hydrophobic. A characteristic chemical property — the ability to form molecular complexes with many salts, acids, amines, proteins etc. Most cholesterol in animal tissues is present in the form of esters of fatty acids.
Fifty nine million three hundred ninety eight thousand two hundred seventy one
By the way.:
In plants there is no cholesterol — no and no, so the inscription on the bottle of vegetable oil "contains no cholesterol" — very true. In plants, there are other sterols, known as phytosterols, molecular structure similar to steroid hormones. They are often added in cosmetics is prohibited for this purpose human hormones. Whether they act on the skin or only the mood of consumers is also a topic for another article.We speak of "cholesterol" — mean "atherosclerosis". We say "atherosclerosis" — mean "cholesterol". And is it true? In fact, the cholesterol would have to rank at least the vitamins! The normal functioning of a number of vital systems of the human body is not possible without cholesterol.
Cholesterol is absolutely essential as a building material for cell membranes during cell division. It is especially important for a growing child's body. Not one cell in our body can't do without him, as "cholesteric structure" is the basis of cell membranes, regulates their permeability and activity of membrane enzymes. The amount of cholesterol in the membrane to a certain extent depends on the strength of the cell, its ability to survive. It protects intracellular structures against the destructive action of free oxygen radicals that are formed during metabolism and under the influence of external factors.
Breast milk is rich in cholesterol. Infants and growing children need fat-rich and cholesterol products, including the full development of the brain and nervous system.
According to the data of radionuclide studies in the human body contains up to 350 grams of this substance: 90% in the tissues and 10% in the blood. About 20% of the total amount of cholesterol contained in the brain and spinal cord — it is a structural component of the myelin "insulation" of the nerves. In plasma it is in the form of esters with higher fatty acids and serves as a carrier during their transport.
In the liver from cholesterol synthesized bile acids are necessary for emulsification and absorption of fats in the small intestine. For this purpose goes 60-80% of the daily formed in the body of cholesterol.
Cholesterol is the "raw material" for the production of steroid hormones of the adrenal cortex (hydrocortisone and aldosterone), and both male and female sex hormones (estrogens and androgens). In men, the obsession with cholesterol-free foods can be dangerous for sexual activity, and women, very active in the fight against cholesterol, amenorrhea often occurs. Especially pointless adherence to a cholesterol diet of women of childbearing age, since menopause female sex hormones just do not allow the cholesterol to be deposited on the walls of blood vessels.
Seven million two hundred thirty thousand four hundred seventy seven
Close relatives: cholesterol, hormones and vitamin D (image source www.cbio.ru) Cholesterol — a fat-soluble precursor of vitamin D, necessary for calcium metabolism. This is especially important for bone, nervous system, insulin production, maintain muscle tone, mineral metabolism, the immune system and for normal growth and development of the child.
By the way.:
Vitamin D is formed in the skin by action of ultraviolet light. Its content in the food (even in such as fish liver, fatty fish, caviar, eggs, dairy fats). Hypovitaminosis D threatens miners, explorers and young children. Breastfed infants vitamin D deficiency is very common and leads to the development of rickets. The daily adult requirement of this vitamin is uncertain. The inhabitants of the far North in the polar night and babies in the winter to sunbathe under the ultraviolet lamp, and if it is not possible to take vitamin drops or tablets — as long as the doctor ordered: hypervitaminosis D — an unpleasant thing.Cholesterol is required for normal activity of serotonin receptors in the brain. Serotonin, a substance responsible for good mood. Low cholesterol is associated with depression, aggressive behavior and tendency to suicide. Particularly acute is manifested in the elderly. Elderly people with low cholesterol melancholy three times more often than their peers who have a cholesterol — article about it was published in the prestigious medical journal "the Lancet". Recently the American scientists have proved that those people who have managed every conceivable way to lower cholesterol, are more likely to have an accident resulting in death, committed suicide, become victims of violence.
Chemical signal by which glial cells of the brain induce neurons to form new synapses appeared to be cholesterol. Researchers from Boston University have shown that a decrease in the content of cholesterol in the blood may reduce intellectual abilities. (Neuroglia, from GK. neuron "once upon a time, the nerve" and glia "glue" cells in the brain and spinal cord, filling the space between neurons and brain capillaries. Serve to protect and support neurons, provides reactive properties of nervous tissue — scarring, participation in the reactions of inflammation, etc.)
As shown by the results obtained by scientists from Harvard University, a high content of cholesterol associated with a "good" high-density lipoproteins (HDL), by 30-40% reduces the risk of developing Alzheimer's compared to people of the same age group with average cholesterol levels. A lipoprotein is a complex of proteins (proteins), molecules which include fats (lipids) and what is "good" and "bad" lipoproteins, we will examine below.
Since cholesterol is so important for normal functioning of the body, entering it with food (exogenous cholesterol) is complemented by synthesis in cells of almost all organs and tissues (endogenous cholesterol). Especially a lot of it is produced by the liver (80%), in the wall of the small intestine (10%) and skin (5%). Measurements and calculations show that only one third of the necessary cholesterol our body gets from food, and two-thirds are produced by the cells of the body. Daily in the human body is synthesized from 0.7 to 1 g of cholesterol, two times more than the approximately 0.3–0.5 g, which come from food. A relatively small excess or deficiency of cholesterol in the diet, the body compensates for the change of the synthesis of cholesterol. About the consequences of a significant shortage we have already said. But the damage is moderately excessive and even normal receipt of cholesterol with food is highly exaggerated. But to prove it, you need to understand what happens to the cholesterol in the body.
Way cholesterol
Biochemist Konrad Bloch (he emigrated to the United States from Hitler's Germany) and his collaborators in 1942 showed that cholesterol synthesis begins with acetic acid, and unearthed main stages of cholesterol biosynthesis: acetate — cholesterol — fatty acids — sex hormones. Thanks to his discovery, it became clear that cholesterol is a necessary component of all body cells, and that all steroid substances in the human body are produced from cholesterol. In 1964 K. Bloch together with F. Linenum became a laureate of the Nobel prize in physiology or medicine for discoveries concerning the mechanisms and regulation of cholesterol metabolism and fatty acids. The main stages of cholesterol synthesis is shown in Fig.
Eleven million nine hundred seventy one thousand two hundred eighty four
The main stages of cholesterol synthesis At the first stage of this process from three molecules of acetate and coenzyme A is synthesized 3-hydroxy-3-methylglutaryl coenzyme a (HMG-COA). Next, effects of the enzyme HMG-COA reductase is formed mevalonova acid, which about 20 of the subsequent stages is transformed into cholesterol.
Despite the complexity and multistage of these processes, a key enzyme in determining the rate of synthesis of cholesterol is HMG-COA reductase. The work of this enzyme and inhibit the statins — widely promoted lipid-lowering (cholesterol lowering) drugs, which will be discussed later.
The mechanism of cholesterol homeostasis is complex. Intracellular cholesterol content is regulated by two mechanisms. The first of these controls the production of cholesterol by the negative feedback mechanism. The second mechanism of controlling the level of cholesterol in the cell is associated with the regulation of its transport across the cellular membrane from the intercellular space. This transport is carried out with the involvement of receptors of low-density lipoproteins (LDL).
In the exchange of cholesterol involve dozens of enzymes, and a mutation in each of their encoding genes can lead to the malfunction of the entire system. Known, for example, so-called family — inherited forms of hypercholesterolemia (excess cholesterol). These lipid disorders are associated with mutations of the genes encoding the receptor for low density lipoprotein. If the mutant gene is present in only one of the pairs of chromosomes, a so-called heterozygous form of hereditary hypercholesterolemia (in America and Europe, it occurs in one out of 500 people), if two mutant genes are homozygous (found in one person out of a million). In both cases suffer from the LDL receptors located on the surface of hepatocytes — liver cells. These receptors play an important role in the metabolism of cholesterol, as LDL is one of its vectors.
The cholesterol metabolism in hereditary familial hypercholesterolemia is a genetic disease inherited in dominant pattern and characterized by extremely high blood levels of LDL and accumulation of cholesterol in tissues — involved Michael brown and Joseph Goldstein. In 1985 they were awarded the Nobel prize in physiology and medicine for his outstanding discoveries concerning cholesterol metabolism and treatment of disorders of cholesterol in the blood.
It should be emphasized that today, studied not only the genes encoding the LDL receptors, but also genes encoding, for example, the protein part of lipoproteins, proteins A and B that play an important role in the ability of these molecules transfer cholesterol.
Incidentally, genes that control the synthesis of cholesterol in the human body, playing an important role in determining life expectancy. Mutation of one of the genes occur in 25% of older people and only have 8.6% of people under 30 years of age. In other words, they accumulate with age, that is trigger the development of senile changes.
Paradoxically, advances in mechanisms of biosynthesis and cholesterol metabolism is not something that ignore and hide from the public, but do not promote — in accordance with the social order. As information about the dangers of TRANS isomers of fatty acids, which are converted to vegetable fats in the production of margarine — a product of supposedly "diet" and "useful" and do not contain cholesterol. (TRANS-isomers of fatty acids and all the history of margarine is also a topic for a separate conversation.)
Doctors, the most advanced of the patients know that cholesterol from food is not associated with atherosclerosis — except in extreme cases like the Atkins diet, when the biochemistry of the body turned inside out because of the monstrous amounts of fat and severe lack of carbohydrates. But the main and mandatory medical recommendation for the prevention and treatment of atherosclerosis is to eliminate from the diet all fatty, and the eggs, brains and other cholesterol-rich foods and to replace animal fats for vegetable oil and margarine.
It is likely that you will recommend taking statins — the main and the miraculous (according to the developers and vendors) means "cholesterol". I wonder how the manufacturers of products and medications get doctors such doublethink? Am using only a single advertisement? published
P. S. And remember, only by changing their consumption — together we change the world! ©
Join us in Facebook , Vkontakte, Odnoklassniki
Source: cbio.ru/page/47/id/2127/
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