Western diets linoleic acid

Linoleic acid (LA or 18 2n-6) An 18-carbon, two double-bond fatty acid. It is the most predominant PUFA in the Western diet. It is found in mayoimaise, salad dressings, and in the seeds and oils of most plants, with the exception of coconut, cocoa, and palm. Linoleic acid is metabolized into longer-chain fatty acids, such as arachidonic acid and gamma-linolenic acid, in animals through a process of chain elongation and desaturations. 

It has been suggested that the Western-type diet is currently deficient in omega-3 fatty acids, which is reflected in the current estimated omega-6 (linoleic acid, arachidonic acid) to omega-3 dietary ratio of about 20-25 1, compared to the 1 1 ratio on which humans evolved. " This has... 

The endothelial dysfunction during the postprandial phase after a meal rich in oxidized fat is almost certainly due to the cellular response to oxidized fat originating from this repeatedly heated fat. As in so many cases, the precise identity of this factor is not known. It is often assumed that it is a reactive molecule, derived from quantitatively the most important unsaturated fatty acid (linoleic acid) in the diet. Thus 9-, 11-, and 13-hydroperoxy-linoleic acids are possibilities, as are 8,9- or 11,12-epoxy-linoleic acids. However, the relative amount of epoxy fatty acids in the diet is much less than that of hydroperoxy fats. Photooxidation products of oleic acid cannot be excluded either, and it is worth pointing out that this unsaturated fatty acid is quantitatively the most important fatty acid in Western and Mediterranean diets. What is also not clear is whether endothelial dysfunction during postprandial lipemia requires the induction of enzymes. 

The omega fatty acids are polyunsaturated fatty acids (PULA), considered as essential nutrients since mammals including humans are unable to synthesize unsaturated fatty acids with a double bond at the n-6 (cob) or the n-3 (co3) position in the cis orientation [140]. The substrate for co-6 series is linoleic acid (18 2n-6), while a-linolenic acid serves as the substrate for 18 3n-3 series. The fatty diet of humans in the Western world has changed from 1 1 ratio of co-6 to co-3 fatty acids [97] to close to a 10 1 (co 6/co 3) ratio because of the increased use of oils rich in LA [141]. 

The most remarkable dietary difference between Arctic or Japanese and European or North American populations has clearly been demonstrated to be the composition of ingested polyunsaturated fatty acids. The primary polyunsaturated fatty acids in the Eskimo or Japanese diet are of the cu-3 family, consisting largely of eicosapentaenoic acid (20 5, o>-3) and docosahexaenoic cid (22 6, a>-3) rather than linoleic acid (18 2, cu-6), which is the predominant polyunsaturated fatty acid in the so-called average or Western diet ([6, 99] Table 3). 

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