Talk:Essential fatty acid

There are two essential fatty acids Linoleic(Octadecadienoic) and Linolenic (Octadecatrienoic) Acid - all the "rest" can be manufactured in the body. One word of caution is that high levels of hydrogenated oils (trans fats) inhibits the absorption and utilization of essential fatty acids, hence the need to supplement in a modern diet.

An article "The Essential Fatty Acid Story and New Ideas for their application" captures the biochemistry as accurately (May 1984, Cosmetics and Toiletries, Vol 99, No.5 p45) as anything currently on the Wikipedia site.

(By the way Vitamin F (Essential fatty Acids)was discussed in 1929 in the Jnl of Biological chemistry, 82, 345, 1929 (G. Burr and M. Burr)): (User: Geoffrey Brooks 208.106.97.239 (talk) 00:12, 16 June 2009 (UTC))

Template:Wikiproject MCB

Which are really essential?

It's not quite clear from the article which essential acids really are essential. Is it only alpha-linolenic acid and linoleic acid or also the other ones listed? On the one hand, it's implied that the other ones can be synthesized by the human body; on the other hand "ω-9 fatty acids are not essential in humans, because humans possess all the enzymes required for their synthesis" follows -> doesn't the same apply to the listed fatty acids excepts linoleic and linolenic? 218.185.73.130 12:35, 28 February 2006 (UTC)

Obviously the ONLY essential EFAs are LNA an LA, since all the other described important derivatives ARE synthesized in the human body. That's the definition of essentiality, isn't it? However in the article there is no clear indications that EFA and AA are NOT essential. I wonder weather it would be wise to mention them in an article describing "Essential fatty acid"s. I think the only justification to mention them is that ingestion of EPA,AA etc may help reduce the amount of required LA and LNA. And that there are circumstances when the synthesis of them in humans can be impaired (that is: excess SFAs, excess MUFA, alcohol and more). Should I change this? regards --62.104.72.134 14:39, 11 May 2007 (UTC) (ingosp from german wiki)

Agreed, though confused by your shorthand. The only essential fatty acids from a nutritional standpoint are α-linolenic acid (ALA) the omega-3, and linoleic acid (LA) the omega-6. Everything I learned in nutrition says EFAs are only those the body can't synthesize. The body can synthesize the longer chain omega-3s and 6s from these, ergo they are not essential. They are "essential" in that the body needs them to function properly, but it can make them (or ingest them). I actually think the marketing term EFA has taken over the scientific one. And that just isn't right. That whole second paragraph should be deleted. And someone ought to fix the omega 3 article because that's wrong, too. Sigh Ns (talk) 07:08, 28 November 2007 (UTC)

Sigh. We can go round and round about the meaning of the term essential. But we're arguing about what a term ought to mean, not what it does mean in common use in the nutritional / biomedicine fields. Since 1932, any of the methylene interrupted even-carbon ω-3 or -6 straight-chain fatty acids are termed 'essential fatty acids' because any of them will relieve the worst symptoms of fat deficiency. And there's abundant evidence that the human body cannot synthesize adequate amounts of long-chain ω-3s, even with abundant linolenic acid in the diet, at least for a large number of adults.

David.Throop (talk) 04:56, 29 November 2007 (UTC)

walnut oil and flaxseed oil

"Some of the food sources of omega-3 fatty acids are fish and shellfish, flaxseed, walnuts, and canola oil." What about walnut oil and flaxseed oil? Do they contain omega-3 fatty acids? Guaka 14:25, 23 Aug 2003 (UTC)

Absolutely. A significant amount of the oil in flaxseed oil is w3. Frankg 17:06, 12 January 2006 (UTC)

Also, plants have ALA omega-3, algae has DHA, and fish both DHA and EPA. Sigh Ns (talk) 07:11, 28 November 2007 (UTC)

what is essential fatty acids

"The most common fatty acids of each class are linolenic (18:3), EPA (20:5), DHA (22:6) for omega-3 and linoleic (18:2) and arachidonic (20:4) for omega-6." What do these numbers mean? Can someone add some prose, or at least a wikilink that can explain them? Guaka 14:30, 23 Aug 2003 (UTC)

• NOTE: C-18:3 means a fatty acid with an 18 Carbon chain and 3 double bonds.

    courtesy Ben Best

What years??

1. What year was it first designated as "Vitamin F"??
2. What year was it decided it should go with the fats??

66.245.109.165 00:32, 18 Aug 2004 (UTC)

Table

I propose utilizing the following table on the article. The table is used in Finnish version.

Fatty acids in nutrirional fats (%)

Fat	ALA	EPA	DHA	ETA	SDA	LA	AA	DGLA	GLA	PA	OA
	n-3					n-6				n-7	n-9
Butter
Coldpressed.rapeseed-	10				0	22			0		63
Olive-	0,5				0	10			0		77
Hempseed-	21				2	57			4		6
Sunflower-	0,4					62
Linseed-	58				0	13			0
Soy-	7					52
Sesam-	0				4	40				10	40
Almond-					1	25				6	65
Fishliver-
Cod-

Fatty acids in nutrirional fats (%)

Fat	ALA	EPA	DHA	ETA	SDA	LA	AA	DGLA	GLA	PA	OA
	n-3					n-6				n-7	n-9
Butter
Coldpressed.rapeseed-	10				0	22			0		63
Olive-	0,5				0	10			0		77
Hempseed-	21				2	57			4		6
Sunflower-	0,4					62
Linseed-	58				0	13			0
Soy-	7					52
Sesam-	0				4	40				10	40
Almond-					1	25				6	65
Fishliver-
Cod-

Eicosatetraenoic acid/Arachidonic acid

Other sources I've read indicate that these two fatty acids are the same thing (two names for the same molecule). This page lists one as w3 and the other as w6. Does anyone know more about this kind of thing and can confirm/deny this? Frankg 17:06, 12 January 2006 (UTC)

Another name for Arachidonic acid is "5,8,11,14-Eicosatetraenoic acid", per CID 231 from PubChem. --Arcadian 17:34, 12 January 2006 (UTC)

So, does that mean that this page is incorrect? Or is there more than one type of eicosatetraenoic acid? Frankg 21:17, 12 January 2006 (UTC)

There are two types of eicosatetraenoic acid. Actually, more than two, but only two are of interest here. Arachidonic acid is all-cis 5,8,11,14-Eicosatetraenoic acid. The ω-3 one is all-cis 8,11,14,17-Eicosatetraenoic acid. They're isomers. A similar situation holds with Docosapentaenoic acid. I'll add an entry and some explanation at Eicosatetraenoic acid. David.Throop 19:26, 22 February 2006 (UTC)

Nomenclature, sources, effects in body

I've clarified the nomenclature. If anyone has access to a program that turns out better molecular diagrams I'd welcome the improvement. I see several problems with the suggested table of sources. Several rows and columns are completely empty, and most of the column headings are abrreviations that aren't defined. No source of the data is listed. A table large enough to be encylopedaic would overwhelm the rest of this article. So if we're going to add such a table it should be a separate page.

Instead, I added citations to several rich sources on the web.

I also extended the listing of bodily fates. The citations most are at the main articles, but I still need a citation for the effects in lipid rafts and DNA activation.

David.Throop 18:08, 3 February 2006 (UTC)

Redundant links in abbreviations

I removed the links to EPA, DHA and ARA in the Examples section because they were either pointing to exactly the same place as the spelled out form, or they were pointing to disambiguation pages. David.Throop 19:14, 22 February 2006 (UTC)

EFA Example Diagram

The SDA diagram has been replaced with an ALA diagram because, strictly speaking, SDA is not essential and ALA is; SDA may be created in the body by metabolizing ALA. Because the topic is Essential Fatty Acids and the modern definition of essential is "cannot be produced, must be ingested", then ALA fits this topic (as does linoleic acid). However, it should be noted that in some people - e.g. diabetics, alcoholics - SDA may be considered essential because the metabolic pathway (Δ6 desaturase step) from ALA to SDA may be severely constricted. Istvan 14:30, 14 March 2006 (UTC)

I partially reverted this edit so it again shows stearidonic acid. I understand your reasoning for preferring ALA. I originally was going to use ALA as the example. But the section is on nomenclature. ALA has 3 double bonds and the first one is three from the omega end. So when an unfamiliar reader sees 18:3 n-3, it isn't immediately clear which 3 is denoting the number of double bonds and which one is denoting the position of the first double bond. That's why I chose stearidonic acid – 18:4 n-3 – as the example. If you really don't like having stearidonic acid as the example, I suggest illustrating with EPA.

I also changed your use of 'methyl' to 'CH₃' to match the usage elsewhere in the paragraph.

By the way, thanks for all the cleanup you've been doing lately on this and related topics. David.Throop 18:08, 14 March 2006 (UTC)

Thanks for noticing:) I see you are also quite active on the lipid sites. I now see your point about the ambiguity of n3 vs. 18:3 What do you think about using linoleic instead? Technically its also "essential" by the strict definition, and there is an available illustration (but its not marked up as well as the ALA diagram - I wish I could mark them up but lack the software). Istvan 18:19, 14 March 2006 (UTC)

references

This page needs more references to scholarly work/research done on essential fatty acids. If you know of any, please add it to the references section of the article. thank-you.

Have at it (as far as EPA and DHA) PUFA Newsletter Sigh Ns (talk) 00:25, 10 August 2008 (UTC)

Permutations?

In reference to LA and LNA, someone wrote, "These four fatty acids (in two permutations of the two listed) cannot be synthesised by humans..." What are the two permutations of these molecules? Frankg 19:07, 5 August 2006 (UTC)

I changed this back to "These two fatty acids ...". Permutations of fatty acids sounds like nonsense. The author who changed it did not explain it. Please explain better if i am wrong here. -- 84.190.151.5 21:34, 16 November 2006 (UTC)

wording of essential definition

Sorry, Tyciol, I reverted your edit. I put in another alternative wording which isn't perfect either. Maybe we can both work on it and come up with something better. Mere presence in tissue is not the only evidence that linolenic acid and linoleic acid are essential. Some other omega-3's and omega-6's are sometimes referred to as EFA's; they are only by a looser definition of this term, but the two I just mentioned really are essential. "base" would not be a better term because it's not what's used to refer to vitamins and minerals. "base" would certainly not be a better term for the derivatives. --Coppertwig 14:30, 23 November 2006 (UTC)

Naming of page

Why is the page called "Essential fatty acid" if there are more than one? I suggest a rename to "Essential fatty acids". --Liface 22:12, 2 July 2007 (UTC)

Fats vs acids

"Almost all the polyunsaturated fats in the human diet are EFAs." How can this be true? Fats are triglycerides (sometimes called "neutral fats"), not acids, right? What is meant by this statement? Unfree (talk) 10:44, 23 May 2008 (UTC)

References for "Heart Health" of effects:

^ "External blockade...by polyunsaturated fatty acids" . PMID 43279. Retrieved on 2007-01-18. - see page 1 of this link ^ "Antiarrhythmic effects of omega-3 fatty acids" . PMID 16919517. Retrieved on 2007-01-18. ^ "Alpha-linolenic acid, cardiovascular disease and sudden death" . PMID 17086218. Retrieved on 2007-01-18. ^ "Omega-3 and health" . PMID 17091903. Retrieved on 2007-01-18.

These references may link a lower LA levels, along with an increased in ALA, with increased heart health, this is not a health benefit of the fats. Simply because a source is legitimate does not make it is useful for the topic. The health effects of EFA should be about what these acids do in the body, with a link to the heart effects of excessive saturated fats.

http://www.fi.edu/learn/brain/fats.html —Preceding unsigned comment added by 72.224.246.134 (talk) 20:09, 22 August 2008 (UTC)

Omega -7?

The article needs at least some mention of Omega-7 and a disambiguation link from the paramilitary group Omega-7.--Shantavira|^{feed me} 14:29, 5 February 2009 (UTC)