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Fats - I Good day to you all, Another very important aspect of our nutrition is ...FATS. Let's see what are fats. (taken from the life science course, written by Mike Benton) Fats, or hydrocarbons, are one of the 3 food categories, the other 2 being proteins and carbohydrates. Fats are composed of the same 3 elements as carbohydrates- carbon, oxygen, and hydrogen. However, they are much poorer in oxygen and richer in carbon and hydrogen than are carbohydrates. Because of this higher carbon and hydrogen content, fats have a greater heat and energy equivalent than carbohydrates. The fats found in plants are manufactured from water and carbon dioxide with the aid of chlorophyll, much in the same manner that the carbohydrates in plants are produced. The fats found in humans and animals come from 2 sources, from the fat in the diet and from the metabolism of excess carbohydrates into fat. The greatest amount of fat in the body usually comes from carbohydrate metabolism. As far as the human digestive process is concerned, fats are composed of 2 components, glycerine and fatty acids. Glycerine is the energy source of fats and is metabolised much in the same manner as are the carbohydrates. The glycerine is broken down into sugars, which may be used by the body for fuel. The fatty acids are often spoken of as chains of hydrogen, carbon & oxygen atoms. Simplistically speaking, the fatty acids are to fat what the amino acids are to protein. These chains of fatty acids have links within them where additional hydrogen, oxygen or carbon atoms may be attached to the chain. If hydrogen is attached to to these links, the fat becomes more solid. This is called hydrogenated fats. All the solid vegetable fats , such as margarines are hydrogenated. If oxygen is attached to one of these fatty acid links, the fat becomes rancid. Thus, fats left exposed to the air begin to oxidise and become rancid rapidly. Fat that is unsaturated is composed of fatty acids in which one or more of the carbon atoms in the chain do not have all their accompanying hydrogen atoms. In other words, unsaturated fatty acids have open available links in the chain. These open links in fatty acid chains are important. The body is able to combine various nutrients with the fatty acid chain through those open links. This combination of nutrients and fatty acids allows both of them to be transported through the body where they can be used in building cell structure. Animal fats contain very little unsaturated fats. The chief sources of unsaturated fatty acids are nuts and seeds. Almost all vegetable fats in their natural state have a high proportion of unsaturated fatty acids. The term Polyunsaturated means that there are a large number of fatty acids, which have 2 or more open links in their chain. . These vegetable polyunsaturated fats are used in making margarine and shortening. This is done by the process of hydrogenation. Hydrogenation causes liquid fats to become hard. If a fat becomes completely hydrogenated, it is rock-hard. The hydrogenation process consists of heating the fats and oils to a temperature of 212 - 400 degrees Hydrogen is then mixed in, along with some catalytic agents, such as nickel or platinum. The fatty acids then take on the hydrogen atoms and begin to solidify. Hydrogenated fats can supply only empty calories and no nutritive value. Since hydrogenated fats cannot become rancid ( nor can they support life ) they are manufactured extensively. Margarines, cooking fat, processed cheeses, lard and peanut butter are but a few products subjected to hydrogenation. Saturated fats are found chiefly in animal fats. Saturated fats are solid at room temperature, unlike the liquid unsaturated fats. Saturated fats are found in animal flesh, dairy products, eggs and coconuts. It should be noted that the saturated fats in coconut have a different chemical. Like hydrogenated fats, the saturated fats cannot enter into a nutrient bonding within the body. The saturated fats are usually empty calories that contribute to a fat build-up within the body. They serve no useful function. Next week we will see how the body uses fat. Stay well, The Crazy Nut Team