In this "Comparatively Speaking," industry expert Tony O'Lenick explains the difference between essential fatty acids and trans fatty acids.
Both essential fatty acids and trans fatty acids are fatty acids. Fatty acids are compounds that contain both a carboxylic group (-COOH) and an alkyl group. The alkyl groups can be either saturated (no double bonds) or unsaturated (double bonds) with double bonds.
Essential Fatty Acids
Essential fatty acids are fatty acids that the body needs but are not made by the body in sufficient quantities for the body to use. For this reason, they must be present in the diet. Essential fatty acids are primarily used to produce hormonelike substances that regulate a wide range of functions including: blood pressure, blood clotting, blood lipid levels, the immune response and the inflammation response to injury infection.
Essential fatty acids are polyunsaturated, i.e., they have several double bonds, and include omega-6 and omega-3 fatty acids. They are essential in the human diet because humans lack the ability to introduce double bonds in fatty acids beyond carbons 9 and 10, as counted from the carboxylic acid side.
Humans, like all mammals, also do not have the enzymes necessary to introduce a double bond at the omega-3 position or omega-6 position. However, humans can easily make saturated fatty acids or monounsaturated fatty acids with a double bond at the omega-9 position.
Essential fatty acids are important in several human body systems, including the immune system and in blood pressure regulation, since they are used to make compounds such as prostaglandins. The brain has increased amounts of linoleic and alpha-linolenic acid derivatives.
Trans Fatty Acids
In contract, trans fatty acids do not occur in nature. They are unsaturated fatty acids that contain a trans double bond between carbon atoms. Naturally occurring unsaturated fatty acids are cis. The trans structure makes metabolism more difficult. Trans bonds are produced during industrial processes like the hydrogenation of vegetable oils. Research suggests that amounts of trans fats correlate with circulatory diseases such as atherosclerosis and coronary heart disease more than the same amount of cis fats.
Applications in Personal Care
Essential fatty acids are common ingredients in skin care. Since they are not produced in sufficient quantities by the body, they can benefit the skin in a number of ways when applied topically; for instance, essential fatty acids can aid skin in dryness and the appearance of aging. On the other hand, it is not currently known whether topical application of trans esters has an impact on health.
More information on the application of essential fatty acids in skin care is available in "Applications of Essential Fatty Acids in Skin Care, Cosmetics and Cosmeceuticals," an article by J. Brenner that appeared in the March 2004 issue of Cosmetics & Toiletries magazine.