unsaturated fatty acid

A fatty acid that contains one (monounsaturated) or more (polyunsaturated) double bonds between carbon atoms. Each double bond takes the place of one hydrogen atom. In cis fatty acids, the two hydrogen atoms adjacent to a double bond are on the same side. This imposes a kink in the molecule making cis unsaturated fatty acids less easy to pack together. Consequently, cis unsaturated fats are usually liquid (oil) at room temperature. In trans-unsaturated fatty acids, the two hydrogen atoms adjacent to a double bond are on opposite sides, enabling the atoms to pack more closely together and giving the trans unsaturated fatty acids physical properties similar to saturated fatty acids. Eating large amounts of foods with high levels of trans unsaturated fatty acids is generally regarded as more detrimental to health than eating comparable amounts of food containing cis unsaturated fatty acids.

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A fatty acid, such as oleic acid, whose carbon chain possesses one or more double or triple bonds and hence can incorporate additional hydrogen atoms.

Any of a number of glyceryl esters of certain organic acids in which some of the atoms are joined by double or triple valence bonds. These bonds are split easily in chemical reaction, and other substances are joined to them. Monounsaturated fatty acids have only one double or triple bond per molecule and are found in such foods as fowl, almonds, pecans, cashew nuts, peanuts, and olive oil. Polyunsaturated fatty acids have more than one double or triple bond per molecule and are found in fish, corn, walnuts, sunflower seeds, soybeans, and saf-flower oil.