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Unsaturated fatty acids (UFA)
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Unsaturated fatty acids, UFA, usually come in the form of liquid vegetable oils, while saturated fatty acids are usually found in solid animal fat. The saturated fatty acids are more slowly metabolized by the body than are the unsaturated fatty acids.
The body cannot manufacture the essential unsaturated fatty acid, linoleic; linolenic and arachidonic acids can be synthesized from linoleic acid if it is sufficiently supplied to the body through diet. Wheat germ; seeds; natural golden vegetable oils, such as safflower, soy, and corn; and cod-liver oil contain lecithin and are the best sources of the unsaturated fatty acids.
Unsaturated fatty acids are important for respiration of vital organs and make it easier for oxygen to be transported by the bloodstream to all cells, tissues, and organs. They also help maintain resilience and lubrication of all cells and combine with protein and cholesterol to form living membranes that hold the body cells together.
UFA help to regulate the rate of blood coagulation and perform a vital function in breaking up cholesterol deposited on arterial walls. They are essential for normal glandular activity, especially of the adrenal glands and the thyroid gland. They nourish the skin cells and are essential for healthy mucous membranes and nerves.
The unsaturated fatty acids function in the body by cooperating with vitamin D in making calcium available to the tissues, assisting in the assimilation of phosphorus, and stimulating the conversion of carotene into vitamin A. Fatty acids are related to normal functioning of the reproductive system.
The stomach, small intestine, and pancreas normally produce liberal amounts of fat-splitting digestive enzymes necessary for conversion of fats into fatty acids and glycerols (broken-down fatty acids). These are absorbed through the walls of the intestinal tract and are then transported through the portal vein to the liver, where they are usually metabolized as a source of energy. These changes must take place before the nutrients can enter the blood without causing food allergies.64
The digested fat is taken from the gastrointestinal tract as fatty acids and glycerol. These then enter fat-collecting ducts that finally carry the fat to the lymphatic system, which is primarily concerned with collecting body fluids and returning them to the general circulatory system. The fatty acids are stored in the adipose (containing massive amounts of fat cells) tissues.
Absorption of fat is decreased when there is in- I creased movement in the gastrointestinal tract and | when there is an absence of bile to break down the I fat. X-ray treatments and radiation destroy the essential fatty acids within the body, although destruction can be prevented if large doses of vitamin E are taken. UFA are easily destroyed when exposed to air and may become rancid.
The National Research Council states that the fat intake should include essential unsaturated fatty acids to the extent of at least 1 percent of the total calories. The level of essential fatty acids needed by infants has been set at 3 percent of the total calories. The need for essential fatty acids is usually met when 2 percent of the calories are produced by linoleic acid, which is found in food sources such as the vegetable oils of soy, corn, sunflower, and wheat germ.
The need for linoleic acid increases in proportion to the amount of solids eaten. If the intake of saturated fats is high, a deficiency of linoleic acids can occur even though oils are included in the diet, and increased consumption of such foods as butter, cream, and saturated fat increases the need for UFA. Eating a great deal of carbohydrates also increases the need for unsaturated fatty acids. When there is sufficient linoleic acid in the diet, the other two essential fatty acids can be synthesized from it.
In order to get the full benefit of UFA, one should take vitamin E with it at mealtimes. This ensures the best absorption. In addition, it is important that as the amount of oils and fats is increased, the dosage of vitamin E is increased.
A diet including UFA should include the antioxidants, such as vitamins A, C, and E and zinc and selenium. These antioxidants prevent the formation of harmful peroxides that result when oxygen and the UFA interact in the body. If the peroxides or free radicals are allowed to form, serious damage to various body proteins can result.
There are no known toxic effects of UFA; however, excessive amounts of saturated fats may cause metabolic disturbances and abnormal weight gain.
Deficiency Effects and Symptoms
UFA deficiency causes changes to occur in the structure and enzyme function within the nucleus of the cells, resulting in a number of disorders. A deficiency may be responsible for brittle and lusterless hair, nail problems, dandruff, and allergic conditions. In addition, diarrhea, varicose veins, underweight, and gallstones may be a result of UFA deficiency. Skin disorders such as eczema, acne, and dry skin have been linked with UFA deficiency; also ailments, such as diseases of the heart, circulatory system, and kidneys, associated with faulty fat metabolism. Without UFA, growth is retarded, teeth do not form properly, and prostaglandins, a group of fatty acids found in tissues of the prostate gland, brain, kidney, and seminal and menstrual fluid, cannot be made by the cells.
Beneficial Effect on Ailments
Unsaturated fatty acids have been used to treat external ulcers, especially leg ulcers, with good results. The unsaturated fat preparation causes rapid granulation and regeneration of the skin. It can also be used orally and externally for treating infantile eczema and the nonallergenic eczema that occurs in adolescents and adults. Psoriasis can benefit from treatment with unsaturated fatty acids. Arachidonic acid is effective in curing dermatitis.
Linoleic acid is effective in restoring growth. Hay fever has been successfully treated with UFA. It is also essential for the prevention and treatment of bronchial asthma and rheumatoid arthritis.
UFA have been used in preventing heart disease. They keep cholesterol soft and prevent it from forming any hard deposits in the lumen of the blood vessels or under the skin. This is especially important for the atherosclerosis patient. Because UFA lower blood cholesterol, they help prevent high blood pressure and hardening of the arteries.
Unsaturated fatty acids have helped prevent diarrhea and underweight. They have been useful in preventing prostate trouble and arthritis. Any person who has gallbladder problems or has had one removed needs to take extra bile in the form of a food supplement so as to ensure proper breakdown of fats.
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