Monunsaturated fatty acid diet
Monounsaturated fatty acids are liquids at room temperature and semisolid or solid when refrigerated. By contrast, polyunsaturated fatty acids (PUFAs) have more than one double bond. Hence oleic acid can be further labeled 18:1n-9, meaning that there is a single double bond, 9 carbon atoms from the omega (n) end of the molecule. Note that the numbering scheme for double bonds starts at the omega or methyl end of the fatty acid whereas the numbering of carbon atoms starts from the carboxyl end of the carbon backbone. Fatty acids are long-chained molecules having an alkyl group at one end and a carboxylic acid group at the other end. Polyunsaturated fats protect against cardiovascular disease by providing more membrane fluidity than monounsaturated fats, but they are more vulnerable to lipid peroxidation ( rancidity ). Oleic acid has 18 carbon atoms with the first double bond occurring 9 carbon atoms away from the carboxylic acid group. For a discussion on how dietary fats affect cardiovascular health, see Diet and heart disease. S. In the diagram below, you see a geometrically correct diagram of oleic acid. , it is also a good source of monounsaturated fats. More physical activity was associated with a higher-oleic acid diet than one of a palmitic acid diet. Levels of oleic along with other monounsaturated fatty acids in red blood cell membranes were positively associated with breast cancer risk. Below is a list of the common and numeric names for monounsaturated fatty acids that may occur in foods. When a single double bond occurs in a fatty acid, it is useful to know the position of the double bond. It can be lengthened to the 18-carbon cis-vaccenic acid. When this configuration occurs, we must add another dimension to the naming scheme.
Notice in both diagrams of oleic acid that the hydrogen atoms occur on the same side of the double bond, rather than on opposite sides. When contrasted to saturated fatty acids, dietary monounsaturated fatty acids lower blood cholesterol concentrations. Oleic acid (18:1) means that the fatty acid is 18 carbon atoms in length and there is a single (:1) double bond. Odd numbered monounsaturated fatty acids are infrequently present in foods. The most common monounsaturated fatty acid in both plant and animal foods is oleic acid (18:1). Monounsaturated fats and low SI in erythrocyte membranes are predictors of postmenopausal breast cancer. The saturation index (SI) of the same membranes was inversely associated with breast cancer risk. The naming scheme for monounsaturated fatty acids follows that for saturated fatty acids. Palmitoleic acid has 16 carbon atoms with the first double bond occurring 7 carbon atoms away from the methyl group (and 9 carbons from the carboxyl end). Monounsaturated fatty acids most frequently occur in higher concentrations in plant foods such as olive oil, most nuts, and avocados. In biochemistry and nutrition, monounsaturated fatty acids (abbreviated MUFAs, or more plainly monounsaturated fats ) are fatty acids that have one double bond in the fatty acid chain with all of the remainder carbon atoms being single-bonded. As was the case with saturated fatty acids, most monounsaturated fatty acids are even numbered. Although marrow from animal bones is infrequently consumed in the U. Below is a schematic diagram of oleic acid or 18:1n-9. The illustrations below show a molecule of oleic acid in Lewis formula and as a space-filling model.
