News tagged with polyunsaturated fatty acids

Related topics: fatty acids

Vitamin B and omega-3 supplementation and cancer: new data

Researchers from the Nutritional Epidemiology Joint Research Unit have just published a study showing that, in men with a previous history of cardiovascular pathologies, supplementation with B vitamins and omega-3 polyunsaturated ...

Feb 17, 2012
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Lipids boost the brain

Consuming oils with high polyunsaturated fatty acid content, in particular those containing omega-3s, is beneficial for the health. But the mechanisms underlying this phenomenon are poorly known. Researchers ...

Aug 11, 2014
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Polyunsaturated fat

In nutrition, polyunsaturated fat is an abbreviation of polyunsaturated fatty acid. That is a fatty acid in which more than one double bond exists within the representative molecule. That is, the molecule has two or more points on its structure capable of supporting hydrogen atoms not currently part of the structure. Polyunsaturated fatty acids can assume a cis or trans conformation depending on the geometry of the double bond.

The lack of the extra hydrogen atoms on the molecule's surface typically reduces the strength of the compound's intermolecular forces, thus causing the melting point of the compound to be significantly lower. This property can be observed by comparing predominately unsaturated vegetable oils, which remain liquid even at relatively low temperatures, to much more saturated fats such as butter or lard which are mainly solid at room temperature. Trans fats are more similar to saturated fat than are cis fats in many respects, including the fact that they solidify at a lower temperature.

A fatty acid has a carboxylic acid at one end and a methyl group at the other end. Carbon atoms in a fatty acid are identified by Greek letters on the basis of their distance from the carboxylic acid. The carbon atom closest to the carboxylic acid is the alpha carbon, the next adjacent carbon is the beta carbon, etc. In a long-chain fatty acid the carbon atom in the methyl group is called the omega carbon because omega is the last letter of the Greek alphabet.

Omega-3 fatty acids have a double bond three carbons away from the methyl carbon, whereas omega-6 fatty acids have a double bond six carbons away from the methyl carbon. The illustration below shows the omega-6 fatty acid, linoleic acid.

This text uses material from Wikipedia licensed under CC BY-SA