Talk:Tocopherol

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Correction in chemical Srtucture: delta-tocopherol should have R1 = CH3 rather than H. —Preceding unsigned comment added by 216.64.175.91 (talk) 19:56, 19 October 2007 (UTC)

As a work of U.S. Federal Government agencies, the text in http://www.cc.nih.gov/ccc/supplements/vite.html appears to be a public domain resource which is available to use in this article.

I have taken in some of the text as a start. There is much more.

Contents 1 Removed misinformation 2 Vitamin E Myth (Cuts and Scars) 3 This needs to be rewritten 4 Seperate Vitamin E article needed 5 Accuracy of information... 6 Vitamin E is not simply tocopherol 7 Deficiency 8 Strange chemistry 9 Health "risks" of vitamin E supplementation 10 SMILES 11 Vitamin E supplements 12 Contradiction 13 Effects on skin 14 use as marker in f/MRI 15 In relation to Alzheimer's Disease and the Oxidative stress article 16 Reference # 19 17 deficiency 18 Cannabis 19 Alzheimer's section 20 Wikipedia:Requests for comment/TheNautilus 21 What is dl???

[edit] Removed misinformation

I removed the assertion that "selenium, Coenzyme Q10, and ample vitamin C have been shown to be essential cofactors of natural tocopherols." This is nonsensical: a cofactor is a substance required for an ENZYME to function. You cannot have a cofactor for a vitamin. Vitamins themselves are cofactors or coenzymes. 154.20.96.9 00:08, 4 December 2006 (UTC)

[edit] Vitamin E Myth (Cuts and Scars)

There is no evidence that Vitamin E speeds the healing of cuts or reduces scarring, this is an urban legend. In fact, research suggests that you could make the scar worse by using it, with 33 percent of those applying vitamin E developing contact dermatitis.

Added a source that backs this up, and mentioned some of it (not the contact dermatitis (that sounds worse than it really is, btw)) in the article. 171.71.37.103 21:42, 12 June 2007 (UTC)

[edit] This needs to be rewritten

Don't mean to be blunt, but including the work as it has been, although properly referenced, is considered plagiarism by many. The fact that much of the article is verbatim isn't stated except in the discussion page, and though the reference is provided, gives the reader the impression that this is a primary work.

A "further information" link should be provided in lieu of the text, although I don't see anything wrong with text that has been significantly rewritten/recomposed. --Lionelbrits 10:21, 15 Apr 2005 (UTC)

[edit] Seperate Vitamin E article needed

The other vitamins a to d all have separate articles on the Vitamin effects which social and biological as well as an article on the chemical properties of the molecule(s) which are the vitamin. Tocopherol should be split to separate the Vitamin and chemical elements into 2 articles. Lumos3 6 July 2005 11:09 (UTC)

See [1] for a desciption of how vitamin e and the tocopherols are defined as seperate entities by the IUPAC-IUB Joint Commission on Biochemical Nomenclature (JCBN).

"The term vitamin E should be used as the generic descriptor for all tocol and tocotrienol derivatives exhibiting qualitatively the biological activity of alpha-tocopherol" ......"The term tocopherol(s) should be used as a generic descriptor for all mono, di, and trimethyltocols. Thus, this term is not synonymous with the term vitamin E".

Lumos3 12:49, 5 September 2005 (UTC)

I agree, I was looking for this article with great difficulty. 68.252.234.158 13:15, 11 May 2006 (UTC)

[edit] Accuracy of information...

I find myself concerned with the tone of this article in light of recent research (some of, if not all of which is credible). Additionally, some of the benefits listed have been discredited by recent studies. I believe simply dismissing some of the recently discovered risks as "media hype" is inaccurate, rash, and in some ways outright possibly dangerous. As an informational resource, wikipedians should be more aware of the need to supply as much accurate and useful information as possible in each article, and this one is no exception. Vitamins are not a topic that particularly excite me, but someone who has been working on this article should seriously consider revising it. Miros 17:53, 19 July 2005 (UTC)

[edit] Vitamin E is not simply tocopherol

from http://www.mercola.com/2003/sep/24/tocotrienols.htm

Vitamin E is comprised of two groups of molecules, tocopherols and tocotrienols, each with four forms (alpha-, beta-, gamma-, and delta-tocopherol, and alpha-, beta-, gamma- and delta-tocotrienol). Research is beginning to focus on specific tocopherols and tocotrienols, rather than just "vitamin E." Nonetheless, the vitamin E most often referred to and sold in most stores is a synthetic form called dl-alpha-tocopherol.

Consider the argument listed at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16458936&query_hl=4&itool=pubmed_docsum

that d-tocopherol is not the only type of vitamin E.

Currently, searches for Vitamin E leap directly to a page for tocopherols, though the page acknowledge that tocotrienols are "Vitamin E."

Palm Oil as important source of Vit E

Natural palm oil contains alpha, beta, gamma, and delta-tocopherols and alpha, beta, gamma, and delta-tocotrienols (i.e. all of them!). No other source contains this much vitamin E.

[edit] Deficiency

I came here trying to find out what Vitamin E deficiency does. Despite going on for ages about possible causes of vitamin E deficiency and speculating about vitamin E overdose, it doesn't tell me what the Vitamin actually does and what happens if you don't take it! mgekelly 16:13, 27 May 2006 (UTC)

[edit] Strange chemistry

The article states:

Synthetic vitamin E, usually marked as d,l-tocopherol or d,l tocopheryl acetate, with 50% d-alpha tocopherol moiety and 50% l-alpha-tocopherol moiety, as synthesized by an earlier process is now actually manufactured as all-racemic alpha tocopherol, with only about one alpha tocopherol molecule in 8 molecules as actual d-alpha tocpherol.

I am not a chemist -- but -- if I read the article racemic, it states:

In chemistry, a racemate is a mixture of equal amounts of left- and right-handed enantiomers of a chiral molecule, such a mixture is called racemic.

which implies "all-racemic" means 50%d and 50%l, in seeming contradiction to this paragraph. It finally concludes with "with only about one alpha tocopherol molecule in 8 molecules as actual d-alpha tocpherol" implies a 12%d and 88%l, so this sounds just wrong. linas 04:55, 10 August 2006 (UTC)

Oh, never mind. Figured it out. There are 8 isomers so all-racemic really means 12% of each. That run-on sentance is confusingly worded.linas 05:03, 10 August 2006 (UTC)

Hopefully the details and wording are more clear now.--TheNautilus 23:27, 20 November 2006 (UTC)

[edit] Health "risks" of vitamin E supplementation

I took the liberty of revising the last section of this article on the health risks of vitamin E supplementation, adding in more information about the Annals meta analysis published in 2005. The previous edit seemed to pay too much attention to criticism, whereas the accumulating evidence suggests consistently that there has been lack of benefit to vitamin E supplementation. Andrew73 03:53, 14 August 2006 (UTC)

[edit] SMILES

In case this article ever gets a chemical infobox, the SMILES notation for the molecule as drawn today is "CC(C)CCC[C@@H](C)CCC[C@@H](C)CCC[C@]1(C)CCc2c(O1)c(C)c(C)c(O)c2C". Catbar (Brian Rock) 02:17, 25 August 2006 (UTC)

[edit] Vitamin E supplements

I just carefully read this article, and it certainly appears that there is no value in Vitamin E supplementation. Is that the intended message? RXPhd 21:03, 26 October 2006 (UTC)

Apparently for conventionally oriented editors & physcians. For a more active coverage of the tocopherols and antioxidants story, pls see Orthomolecular medicine: Criticism and controversy as well as Talk[2], [3].---TheNautilus 23:12, 4 November 2006 (UTC)

[edit] Contradiction

In the "Vitamin E and cancer" section of this article, it states:

Recent studies also show that vitamin E acts as an effective free radical scavenger and can lower the incidence of lung cancer in smokers.[18]

When actually reading reference 18 - The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. - it says:

Among the 876 new cases of lung cancer diagnosed during the trial, no reduction in incidence was observed among the men who received alpha-tocopherol (change in incidence as compared with those who did not, -2 percent; 95 percent confidence interval, -14 to 12 percent).

Therefore, the article here is wrong. There have in fact been other large randomized studies since of alpha-tocopherol, including the HOPE study and the Heart Protection Study, neither of which have shown effects on lung cancer.

82.10.96.227 21:18, 19 March 2007 (UTC)

[edit] Effects on skin

Is there any scientific evidence regarding the effect on skin? If not, this should probably be noted, lest we imply the cosmetic manufacturer's claims are true by omitting any reason why this might be doubted. Manufacturers are not a reliable source for medical effectiveness, but information about effectiveness is often what readers come to articles like this for. -- Beland 06:09, 16 April 2007 (UTC)

[edit] use as marker in f/MRI

If you can, please contribute to the vitamin E discussion on the MRI talk page. The questions are:

Is a specific form used? Why / Why not?

Wherefore the hyperintensity?

Are there other suitable, inexpensive markers? If so, what's the history behind the industry's using vitamin E? --Eitch 04:42, 3 May 2007 (UTC)

[edit] In relation to Alzheimer's Disease and the Oxidative stress article

Opinions of the effect of Vitamin E on the prevention of Alzheimer's Disease differ in this and the Oxidative stress article. -- Squater 27 June 2007

[edit] Reference # 19

is blank ???

[edit] deficiency

this page doesn't talk about what is perhaps the most important question about vitamin e: what are the symptoms or consecuencies of vitamin e deficiency?

[edit] Cannabis

This page says that tocopherols may reduce the neurological damage caused by THC, but the article on cannabis suggests that marijuana itself not only doesn't cause damage, but prevents neurotoxicity. One of these has to be rewritten to accommodate the other. 24.65.87.238 19:18, 31 October 2007 (UTC)Whatever my IP is

[edit] Alzheimer's section

Quoting one positive study is a bit misleading, since the evidence is very mixed. I've rewritten the section using reviews on the topic as sources. Tim Vickers (talk) 19:20, 2 May 2008 (UTC)

[edit] Wikipedia:Requests for comment/TheNautilus

Editors of this article would be welcome to participate in this RfC. Tim Vickers (talk) 18:33, 31 May 2008 (UTC)

[edit] What is dl???

The section titled "Alpha-tocopherol" should explain what "dl" means. The interested outsider probably will not have any idea what "dl" means. I came to this article looking for an explanation of "dl" and "ldl" and if it's there I can't decipher it. Olan7allen (talk) 06:12, 14 June 2008 (UTC)