Nutrition rules >>>> Fats in the body
Fats in the body.
Fats or lipids are a large group of chemical compounds found in nature. Fats have a number of typical characteristics that allow them to be identified: they are insoluble in water, but soluble in ether, benzene, chloroform and other non-polar solvents. But at the same time, there are representatives of lipids that dissolve well in water (lysolecithins). In addition, there are compounds of a different order, similar to lipids in their chemical properties, for example, higher hydrocarbons and alcohols, carotenoids, fat-soluble vitamins.
Fats are substances that, in terms of their biological role, are indispensable for metabolic processes and the life support of living organisms. They perform a number of critical functions:
- They are structural elements involved in the formation of the cell membrane and are responsible for the level of its permeability to necessary substances and protection from harmful components;
- They transport useful components along the bloodstream to various organs;
- Participate in the transmission of nerve impulses;
- Participate in enzymatic reactions;
- A layer of subcutaneous tissue is formed, which protects the body from mechanical damage and shock, and also serves as a source of additional reserves of energy substances and a thermal insulating cover;
- Layers of adipose tissue are responsible for the buoyancy of the body, that is, in water, they reduce the average specific weight of the body.
Fats are subdivided into simple (glycerides and waxes), complex (phospholipids, glycolipids, steroids, sulfolipids, aminolipids, and lipoproteins) and lipid precursors and derivatives (fatty acids, sterols, glycerols, fatty acid aldehydes, fat-soluble vitamins and hormones carbohydrates).
Fats are able to be synthesized in the body, and the liver is responsible for this synthesis (the endogenous pathway for obtaining lipids). It is in it that lipid metabolism takes place, the processes of transporting fatty compounds by protein structures (lipoproteins) arise. Endogenous fats are synthesized from some metabolic products of carbohydrates and proteins, and are transported with the blood stream to various organs and tissues.
There are a number of compounds (fat-soluble vitamins and some fatty acids) that must be obtained from the outside (exogenously). Fats obtained exogenously undergo a gradual decomposition and utilization in the small intestine, and are excreted by the kidneys. Exogenous fats are capable of being deposited with their excess intake into the body. The liver is responsible for this function.
The fat molecules deposited and deposited in the fatty tissue can provide an important service to the body during the period of hunger survival, when it is necessary to spend the accumulated fat reserves, gradually oxidizing them. The wonderful ability of fats is manifested at a time when the body does not have enough water (for example, during long journeys in the desert or hibernation in some species of animals). At such moments in life, the breakdown of fats and the birth of water molecules, vital for the body, occurs.
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