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Benefits of Eating Fats and Oils
What are Fats and Oils?
Fats belong to a group of chemical substances known as lipids, greasy to touch and insoluble in water. Chemically true fats are called triglycerides and are made up of these molecules of fatty acids and one molecule of glycerol. Fats resemble the carbohydrates in composition in that they are made up of carbon, hydrogen and oxygen. However, they differ from carbohydrates in the proportion in which these three chemical elements occur, the fats containing less oxygen and more carbon and hydrogen than the carbohydrates or proteins. Fats are concentrated foods, and when burned produce approximately two and one fourth times as much heat as do the carbohydrates or the proteins.
There are a number of fatty acids that in various combinations give to fats their specific characteristics. As a result of these combinations there are fats of varying degrees of hardness; for example, the oils, which are liquid, and beef and mutton fats, which are solid. The fat of cold-blooded animals -fish, for example - is a softer fat and remains plastic at the low temperature to which it is exposed, while that of the warm-blooded animals has a higher melting points and is consequently harder at room temperature. As a rule, the fat of herbivorous animals is harder than that of carnivorous animals. A large part of our supply of fat for cooking is obtained from the former. When adipose tissue of animals is subjected to heat, the fat liquefies and thus separates from the connective tissue cells in which it is deposited.
Four Group of Fats
Fats are energy-giving nutrients and have 9 calories in each gram. Fats aid in the absorption of fat-soluble vitamins A, D, E, and K. Fats are either saturated or unsaturated, and nearly all foods with fat have both kinds. However, in general there are 4 group of fats.
Saturated fats are solid fats in your diet. It is mostly in animal foods, such as dairy products and meat. Poultry and fish contain less saturated fat compared to red meat. Saturated fat is present in most tropical oils, such as coconut oil and palm oil. Tropical oils are used in most snacks and in nondairy foods, including creamers and whipped creams. Consuming foods high in saturated fat can increase the risk of heart disease and bad cholesterol.
This is a fat that undergoes a process called hydrogenation. This process increases the expiration life of fat and helps make the fat harder at room temperature. Harder fat creates crispy crackers and flakier pies. Trans fat can raise your cholesterol levels, so make sure your consume as little trans fat as possible. Trans fat are present in:
- Commercially-processed foods.
- Snack foods, which include chips and crackers.
- Margarine and salad creams.
- Foods containing shortening and partly hydrogenated oils.
Unsaturated fat or fatty acid is liquid at room temperature. It is usually oils derived from plants. In case you eat unsaturated fat instead of saturated fat, it may help your cholesterol levels to normalize. It is better to replace your saturated fat diet with either mono-unsaturated or polyunsaturated fat.
- Monounsaturated fat: This fat is in vegetable oils, canola oils, olive, and peanut oils. Consuming foods that contain monounsaturated fats helps reduce your "bad" LDL cholesterol. Monounsaturated fats can also keep "good" cholesterol levels high. This can cut down the risk of getting heart disease. However having more unsaturated fat without restricting on saturated fat will not reduce your cholesterol.
- Polyunsaturated fat: This type of fat is essentially in vegetable oils such as safflower, sunflower seeds, sesame , soy oils, and corn oils. Other sources include seafood, leafy greens, krill, algae and polyunsaturated margarine. Consuming polyunsaturated fat instead of saturated fat may bring down LDL cholesterol.
Why Do We Need Fats and Oils in Our Diet?
Fat plays a very important part in our diet. They give flavor, texture and seem to act as regulators of the emptying time of the stomach. Food low in fat has poor satiety value because the stomach empties too rapidly. Even in the United states, where the total consumption of fat was not drastically reduced, the average consumer was aware of the change. This was probably due to the fact that the reduction of "visible" fats, i.e fats purchased as such, was greater than the reduction of "visible" fats, i.e fats in natural foods. The human body can make use of either form of fat and can adjust to a reduction in total fat intake without apparent physiological strain. Food habits vary widely as to per-capita fat consumption, yet a drop below the usual level is a cause for discontent. Hence, it is easy to understand the morale value of fat to people who have been subsisting for years on starchy vegetables with little meat or other fats.
How the Body Uses Fats and Oils
Fats Provide Necessary Energy
Although the primary source of energy our body uses is from carbohydrates, fat is utilized by the body as a stockpile of support energy in conditions when carbohydrates become unavailable. This is a potent source of fuel your body can use. But remember, fat contains 9 calories which is doubled compare to the calories found in protein and carbohydrates. It is recommended that 20 to 35% of our daily calorie intake should come from fat.
Fats Absorb Vitamins
Fat soluble vitamins A, D, E, and K are carried by fats in order to be absorbed and stored in the liver and in fatty tissues. Vitamin A is in charge of maintaining good vision and keeping our eyes nerves healthy; vitamin D support in calcium absorption; vitamin E help remove harmful toxins from your body and keep your cells healthy as well; and vitamin K is important to prevent blood clotting. Not enough fat in the body can cause a health risk known as vitamin deficiency.
Fats Help Maintain Cell Membrane
In addition to providing the body useful energy, body fats also support in building and maintaining vital components of cells and tissues particularly the cell membrane.
Fats Protect Vital Organs
Our bodies can be able to store fats to be used in later physical function. When you consume foods that have an additional energy, the excess fat is stored under the skin. Most often this adipose tissue is stored in the thighs and stomach which causes lumpy areas. Our vital organs are also covered with fats to protect from external bumps and any abrupt movements.
Fats Regulate Body Temperature
Under our skin there is a thin fat layer which acts as an insulator that keeps the heat inside our body. This layer helps maintain our body’s proper temperature. Aside from screening the heat in and out, this layer of fat also protects the inner layers from severe and sudden temperature changes. This process happens when our skin temperature substantially drop. The fats stored under the skin will generate and then release heat which helps increase and eventually normalize our body temperature.
Good Food Sources of Fats and Oils
Among the most valuable fats from animals sources are those from milk, cream, butter and egg yolks. The tissues of all animals contain some fats, and many carcasses yield large amounts, especially pork and beef. The livers of fish and animals are rich sources of fats and other lipids, including the "essential" fatty acids.
Numerous vegetables oils, such as olive, peanut, cottonseed, coconut, soybean and corn, are extracted by pressing. Most of the well-known cooking fats other than lard are made from less expensive vegetable oils by hydrogenation. This chemical process involves introduction of hydrogen into the fat molecule under carefully controlled conditions to produce a fat with just the right melting point for most culinary purposes.
Margarine is processed largely from vegetable fats or oils which are churned in cultured milk to give the flavor of butter. When fortified sufficiently with vitamin A to bring its content up to the average of butter, it becomes a good substitute for butter. Sources of vegetable fats are nuts, seeds, chocolate and avocados.
Mineral oil, known also as paraffin oil, is not a true fat and is neither digested nor absorbed by the body. It was formerly used in place of true fats in certain special low-calorie diets. This procedure should be discouraged because mineral oil tends to interfere with the absorption of all the fat-soluble vitamins. It is particularly detrimental when used in a food such as salad dressing or when taken with meals.
In addition to fats, the phospho-lipids and the sterols plays very important roles in metabolism. The phospholipids are compounds consisting of a fat to which is attached a phosphoric-acid radical and a nitrogen-containing base. Two of the most important of this groups are lecithin and cephalin, both important cellular constituents. The phosphoric acid of these compounds is now known to "take part in most of the stages of carbohydrates metabolism."
Lecithin undoubtedly plays and important role in fat metabolism, but just how and to what extent have not been determined. Choline, a part of the lecithin molecule, is now known to be essentials to the prevention of fat accumulation in the liver, a condition known as "fatty liver disease." The phospholipids occur in relatively large amounts in the brain, the liver, the heart, the kidney, the lungs and, to a lesser extent, in all voluntary muscles. Egg yolks are also a rich source.
Sterols are compounds of alcohols with fatty acids and are soluble in fat solvents. Among the most important sterols are cholesterol and ergosterol. Cholesterol is found in all body tissues, especially in the brain and the nerve tissue, the suprarenal gland, the liver and the blood. It is also a constituent of bile and often appears as a morbid product in gallstones and in the kidney. It accumulates in the blood plasma in nephrosis and in diabetes mellitus. The richest food source of cholesterol is egg yolk.
Closely related to cholesterol is ergosterol, both of which are precursors of, and may be converted into, vitamin D by means of irradiation with ultraviolet light. The pure sterols if dissolved in oil or foods, such as milk, may thus be activated by irradiation. Ergosterol is of plant origin, while cholesterol is from animal sources only. When irradiated, ergosterol becomes calciferol, which, when dissolved in oil, is a concentrated source of vitamin D. Commercially,irradiated ergosterol in oil is known as viosterol.
There are three fatty acids recognized as "essential." That is, either they are not synthesized or are not synthesized rapidly enough in the body to meet its needs, and must, therefore, be consumed as constituents of food. They are arachidonic, linoleic and linolenic, the last two being so named because they were first discovered in linseed oil, although they are now known to be constituents of most of the food oils, as well as of egg yolk, butter and the organs and the tissues of animals. The human requirement for these essential fatty acids is apparently small and is ordinarily met easily in the average diet.