What fat is better?
Long time fats were considered as a power source, but were not considered as an obligatory element of food as they can be formed in an organism of carbohydrates and proteins. Really, fat - the most high-calorific fuel: at combustion of 1 gram of fat in fabrics 9 kilocalories are allocated, and 1 gram of carbohydrates gives only 3,75 kilocalories, 1 gram of protein - 4. Therefore when it is necessary to fill considerable energy expenditure of an organism, fats are irreplaceable.
But fat - not a power source. It is used as a structural element of fabrics: in a complex with proteins is a part of cellular covers and intracellular educations. Besides, fats contain a number of vital substances which in an organism either are not synthesized, or are formed in insufficient quantities.
By the chemical nature fats represent esters of glycerin and vital acids. Properties of each type of fat depend mainly on structure and a structure of the fatty acids entering it. In fats which at the room temperature remain in a liquid state fatty nonsaturated acids prevail. The majority of vegetable oils and fat of fishes are that.
Solid fats of animals and birds contain saturated fatty acids. The more in fat of saturated fatty acids, the temperature of its melting is higher, so, its digestion and assimilation is longer. Therefore refractory mutton, beef fats are acquired worse, than, for example, milk fats and vegetable oils.
For an organism fatty nonsaturated acids are of great value. They are necessary for growth of the cages, a normal state of skin, an exchange of cholesterol and many other processes which are made in an organism. The children of early age who are especially raised artificially are most sensitive to their shortcoming. Deficiency of fatty nonsaturated acids in a diet of the child leads to growth delay, ekzematozny changes of skin, decrease in resilience to infections.
Among biologically active agents which are contained in fats it is necessary to call still fosfatida, sterols, and also vitamins A, D, E. The main supplier of vitamins A and D - butter, in vegetable they are absent. Vitamin E, on the contrary, contains in vegetable oil. Fosfatidov is more in vegetable oil. Their main advantage is that they promote fat digestion.
The lack of fosfatid of food leads to accumulation of fat in a liver. Ability of fosfatid, especially lecithin is very valuable, to reduce the content of cholesterol in blood and to interfere with its adjournment in a vascular wall. At fosfatida oil refinement, unfortunately, are lost.
We receive sterols generally with animal fats. The most important of them - cholesterol. Who does not know now that cholesterol is recognized by responsible for development of atherosclerosis, cholelithiasis! It is known much less that cholesterol is an important component of the majority of cages that it regulates permeability of cellular membranes, participates in formation of bilious acids, hormones of gonads and bark of adrenal glands, vitamin D.
In our organism the constant level of cholesterol in blood (from 150 to 250 milligrams - percent) is normal supported irrespective of how many it arrives with food. Therefore healthy people of young and middle age without fears can include the products containing rather large amounts of cholesterol in a diet: all animal fats and, in particular, butter. Certainly, without exceeding at the same time physiological norms. Other business - at advanced age when mechanisms of regulation of an exchange of cholesterol are broken.
Elderly it is expedient to replace part of animal fat vegetable. I highlight: only part of animal fat! At the same time it is proved that the vegetable oil used in moderate quantities possesses zhelchnogonny action. Not only vegetable oils, but also any fats negatively influence an organism if arrive with food much. Experts found out that at long consumption of fat in large numbers obesity develops.
So, on a question what fat is better, the answer can be one: only the combination of various fats guarantees providing an organism with necessary food components. It is impossible to give preference to any one fat as each of animal and vegetable fats contains a number of the useful substances which are absent in other fat.
More stoutly the correct culinary processing of food helps to use advantages of various fats. It is not necessary to fry repeatedly in the same portion of vegetable oil. From long heating acids collapse, substances which irritate a stomach, intestines, a liver are formed. It is the most useful to use vegetable oil in the natural form without heat treatment, adding it to salads, garnishes and other dishes. Melted animal fats most are suitable for preparation of second courses, garnishes, sauces.