Essential Fatty Acids (EFAs) and Health:

[mrsdoubtfyre]

I've started an updated version of my old EFA thread from here (which is lost in the archives from the down).

*******************************.com/showthread.php?t=6092

So I am starting an EFA thread here as well. I am not going to duplicate
everything, but do welcome questions/and comments about the subject, and
posting here of any information you may have that will enrich this subject.;)

That thread is still in progress, I have just started it. It will have other supplement data on it as I get time.;)

[mrsdoubtfyre]

J Nutr Health Aging. 2004;8(3):163-74. Links
Roles of unsaturated fatty acids (especially omega-3 fatty acids) in the brain at various ages and during ageing.

* Bourre JM.

INSERM Research Director. Unit U26 Neuro-pharmaco-nutrition. Hopital Fernand Widal, 200 rue du Faubourg Saint Denis. 75745 Paris cedex 10. jean-marie.bourre@fwidal.inserm.fr

Among various organs, in the brain, the fatty acids most extensively studied are omega-3 fatty acids. Alpha-linolenic acid (18:3omega3) deficiency alters the structure and function of membranes and induces minor cerebral dysfunctions, as demonstrated in animal models and subsequently in human infants. Even though the brain is materially an organ like any other, that is to say elaborated from substances present in the diet (sometimes exclusively), for long it was not accepted that food can have an influence on brain structure, and thus on its function.

Lipids, and especially omega-3 fatty acids, provided the first coherent experimental demonstration of the effect of diet (nutrients) on the structure and function of the brain. In fact the brain, after adipose tissue, is the organ richest in lipids, whose only role is to participate in membrane structure. First it was shown that the differentiation and functioning of cultured brain cells requires not only alpha-linolenic acid (the major component of the omega-3, omega3 family), but also the very long omega-3 and omega-6 carbon chains (1). It was then demonstrated that alpha-linolenic acid deficiency alters the course of brain development, perturbs the composition and physicochemical properties of brain cell membranes, neurones, oligodendrocytes, and astrocytes (2).This leads to physicochemical modifications, induces biochemical and physiological perturbations, and results in neurosensory and behavioural upset (3).

Consequently, the nature of polyunsaturated fatty acids (in particular omega-3) present in formula milks for infants (premature and term) conditions the visual and cerebral abilities, including intellectual. Moreover, dietary omega-3 fatty acids are certainly involved in the prevention of some aspects of cardiovascular disease (including at the level of cerebral vascularization), and in some neuropsychiatric disorders, particularly depression, as well as in dementia, notably Alzheimer's disease. Recent results have shown that dietary alpha-linolenic acid deficiency induces more marked abnormalities in certain cerebral structures than in others, as the frontal cortex and pituitary gland are more severely affected. These selective lesions are accompanied by behavioural disorders more particularly affecting certain tests (habituation, adaptation to new situations). Biochemical and behavioural abnormalities are partially reversed by a dietary phospholipid supplement, especially omega-3-rich egg yolk extracts or pig brain. A dose-effect study showed that animal phospholipids are more effective than plant phospholipids to reverse the consequences of alpha-linolenic acid deficiency, partly because they provide very long preformed chains.

Alpha-linolenic acid deficiency decreases the perception of pleasure, by slightly altering the efficacy of sensory organs and by affecting certain cerebral structures. Age-related impairment of hearing, vision and smell is due to both decreased efficacy of the parts of the brain concerned and disorders of sensory receptors, particularly of the inner ear or retina. For example, a given level of perception of a sweet taste requires a larger quantity of sugar in subjects with alpha-linolenic acid deficiency. In view of occidental eating habits, as omega-6 fatty acid deficiency has never been observed, its impact on the brain has not been studied.

In contrast, omega-9 fatty acid deficiency, specifically oleic acid deficiency, induces a reduction of this fatty acid in many tissues, except the brain (but the sciatic nerve is affected). This fatty acid is therefore not synthesized in sufficient quantities, at least during pregnancy-lactation, implying a need for dietary intake. It must be remembered that organization of the neurons is almost complete several weeks before birth, and that these neurons remain for the subject's life time. Consequently, any disturbance of these neurons, an alteration of their connections, and impaired turnover of their constituents at any stage of life, will tend to accelerate ageing. The enzymatic activities of sytivities of synthesis of long-chain polyunsaturated fatty acids from linoleic and alpha-linolenic acids are very limited in the brain: this organ therefore depends on an exogenous supply. Consequently, fatty acids that are essential for the brain are arachidonic acid and cervonic acid, derived from the diet, unless they are synthesized by the liver from linoleic acid and alpha-linolenic acid. The age-related reduction of hepatic desaturase activities (which participate in the synthesis of long chains, together with elongases) can impair turnover of cerebral membranes. In many structures, especially in the frontal cortex, a reduction of cervonic and arachidonic acids is observed during ageing, predominantly associated with a reduction of phosphatidylethanolamines (mainly in the form of plasmalogens). Peroxisomal oxidation of polyunsaturated fatty acids decreases in the brain during ageing, participating in decreased turnover of membrane fatty acids, which are also less effectively protected against peroxidation by free radicals.

PMID: 15129302 [PubMed - indexed for MEDLINE]
Related Links

ALA= alpha linolenic acid as found in flax oil, walnuts and canola oil.
Long chain fatty acids = DHA and EPA

from http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=15129302

[NevadaGeo]

I just finished reading an extremely interesting new book about EFA's.

Title: "The Queen of Fats"
Subtitle: "Why Omega-3's Were Removed fro the Western Diet and What We Can Do to Replace Them"
Author: Susan Allport

The book includes a rather comprehensive, but very readable, history of the main studies of EFA's from their initial discovery up thru their recognition as essential nutrients and most importantly the discovery that it is the balance of fats in general, not just the overall quantity, that is important. Based on this history, the author presents a very compelling account of how the western diet emphasizes omega-6's at the expense of omega-3's and what this is doing to our health. She also includes general recommendations on how to replace the omega-3's in our present day diets.

I recommend this book to anyone interesting in EFA's.

[mrsdoubtfyre]

I'll have to check it out...

I wonder why it isn't called the KING of FATS? Why make it feminine?:p

[Ted Hutchinson]

I wonder why it isn't called the KING of FATS? Why make it feminine?:pI've just read the fairly extensive exerpt at Amazon (http://www.amazon.com/Queen-Fats-Omega-3s-Removed-California/dp/0520242823) click on the book image, and I think on page 6 where she is discussing the role of EPA as a mediator or peacemaker and a producer of measured reactions from neighbouring cells, she is attributing the concillatory skills of the female sex to this EFA. In other words I think you should take is as a compliment. (though of course in the film Mrs Doubtfire was a man in drag so forgive me if I've wrongly guessed your sex)

I've read the reviews there as well and don't think I'll be investing my money, the last review in particular worried me, I can't understand how anyone spending so much time writing such a book could fail to give a correct indication of the omega 3 content of white as opposed to oily fish or not consider relatively inefficient metabolism of ALA (from sources such as linseed) into EPA and then to DHA.

I appreciate that there has been plenty of new research on this issue recently but doubts about the amount of EPA metabolised from ALA have been around for some time.
Not that anyone should be put off eating plenty of linseed. Alpha-linolenic acid and cardiovascular diseases omega-3 fatty acids beyond eicosapentaenoic acid and docosahexaenoic acid. (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17016414&query_hl=10&itool=pubmed_docsum) shows dietary ALA has been associated with a lower rate of fatal and nonfatal coronary events.

But I may be misjudging the author as I've only read the online material and reviews so I may be displaying my ignorance.