Essential Fatty Acids

In the (essential) fatty acid analyzes (package) in blood, the levels of the (essential) fatty acids and of the trans fatty acids in the membrane of red blood cells are determined. The provisions give the (average) status over a longer period. The determinations are therefore not snapshots such as the determination in serum, which gives information about the status at the moment of blood collection only. The fatty acid levels are given as a percentage of the total (of fatty acids) - so as the amount of the fatty acid compared to the other fatty acids.

The omega-6 fatty acid linoleic acid (LA) and the omega-3 fatty acid alpha-linolenic acid (ALA) are the essential fatty acids for humans. The terms omega-6 and omega-3 refer to the location of the first unsaturated bond, calculated from the terminal carbon atom. People are not able to make the omega-6 and omega-3 fatty acid structures themselves and are therefore dependent on the nutrition for the 'mother structures' of these fatty acids. Linoleic acid (the mother structure for the omega-6 series) is fairly common in vegetable products, especially in seeds and the oil that is made from them. Alpha-linolenic acid (the mother structure for the omega-3 series) is also present in vegetable products, but is less common in this. Alpha-linolenic acid is found mainly in green-leaved plants, linseed (oil), walnuts and soya.

Also the omega-6 fatty acid arachidonic acid (AA) is considered to be the essential fatty acids because this fatty acid is formed only to a very limited extent in the body from linoleic acid. In the diet, arachidonic acid is found in meat. The saturated fatty acids and fatty acids with an omega-9 structure can be formed by humans themselves.

In the liver, (lactic acid and linolenic acid, through extension and desaturation, (other) fatty acids are formed from the omega-6 and omega-3 series, respectively. These fatty acids are in turn important precursors of eicosanoids (prostaglandins, thromboxanes, prostacyclins and leukotrienes). The eicosanoids perform important (regulatory) functions in a large number of metabolic processes, including allergic reactions, blood clotting and inflammatory reactions. From linoleic acid, via GLA, prostaglandin E1 (PGE1) is formed and alpha-linolenic acid is formed, among others, via EPA and DHA, prostaglandin E3 (PGE3). From the fatty acid arachidonic acid also present in the body, prostaglandin E2 (PGE2) is formed.

Because the eicosanoids formed from linoleic acid, alpha-linolenic acid and arachidonic acid have different, often opposite effects, not only shortages, but also disturbances in the ratio (s) of the fatty acids and the substances derived from them can lead to disturbances in body functions.

Nomenclature and structure of the fatty acids

The fatty acids are subdivided into polyunsaturated fatty acids, monounsaturated fatty acids and saturated fatty acids, depending on the number of unsaturated bonds that they contain.

On the basis of their length and the number of unsaturated bonds that they contain, fatty acids are also referred to as 'number: number', the first number being the length of the fatty acid (in C-atoms) and the second number the number of unsaturated bonds. that contains fatty acid. EPA, for example, is designated C 20: 5 - it is 20 C atoms long and contains 5 unsaturated bonds.

The natural fatty acids all have the cis-form. Trans fatty acids do not occur in nature, but they can occur in procedures for hardening fats. Trans fatty acids are metabolically 'unnatural' and are harmful because they interfere with normal fatty acid metabolism.