Monounsaturated fat


 * For discussion how dietary fats affect cardiovascular health, see Diet and heart disease.

In nutrition, monounsaturated fats are fatty acids having a single double bond present in the fatty acid chain, with all of the carbons in the chain single-bonded carbons, in contrast to polyunsaturated fatty acids which have more than one double bond.

Fatty acids are long-chained molecules having a methyl group at one end and a carboxylic acid group at the other end. Fatty acid fluidity increases with increasing number of double bonds. Therefore, monounsaturated fatty acids have a melting temperature that is higher than that of polyunsaturated fatty acids, but still below that of saturated fatty acids.

Common monounsaturated fatty acids are palmitoleic acid (16:1 n&minus;7), cis-vaccenic acid (18:1 n&minus;7) and oleic acid (18:1 n&minus;9). 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). It can be lengthened to the 18-carbon cis-vaccenic acid. Oleic acid has 18 carbon atoms with the first double bond occurring 9 carbon atoms away from the methyl group. The illustration below shows a molecule of oleic acid.

Monounsaturated fats are found in natural foods like nuts and avocados, and are the main component of Tea-oil Camellia and olive oil (oleic acid). They can also be found in grapeseed oil, ground nut oil, peanut oil, flaxseed oil, sesame oil and corn oil. Canola oil is 57%&minus;60% monounsaturated fat, olive oil is about 75% monounsaturated fat whilst Tea-oil Camellia is commonly over 80% monounsaturated fat.

Olive oil is a key component of the Mediterranean diet, widely regarded as being protective against cardiovascular disease while Tea-oil Camellia has been a traditional part of Asian cooking culture. Although polyunsaturated fats protect against cardiovascular disease by providing more membrane fluidity than monounsaturated fats, polyunsaturated fats are more vulnerable to lipid peroxidation (rancidity) than monounsaturated fats. On the other hand, monounsaturated fatty acids (like saturated fats) promote insulin resistance, whereas polyunsaturated fatty acids are protective against insulin resistance.

Foods containing monounsaturated fats lower LDL cholesterol, without lowering HDL cholesterol.

Natural sources of monounsaturated fat

 * Avocados
 * Canola oil
 * Cereal
 * flaxseed oil
 * grapeseed oil
 * ground nut oil
 * Oatmeal
 * Olive oil
 * Peanut oil and other nuts
 * Popcorn
 * Safflower oil
 * Sesame oil
 * Sunflower oil
 * Tea-oil Camellia
 * Whole grain wheat