Vitamin C has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can delist it, or ask for a reassessment.
Article milestones Date Process Result December 3, 2004 Featured article candidate Not promoted February 21, 2007 Good article nominee Listed March 24, 2007 Peer review Reviewed Current Status: Good article

To-do list for Vitamin C:	· history · watch · refresh
Here are some tasks you can do: Copyedit: the section order relating to its content Wikify: fix red links! either create the article from what information you can gather, or, as a last resort, remove the link Cleanup: the references, adding any requested citations and using {{cite web}}, {{cite journal}}, {{cite book}} or {{cite news}} wherever possible "ascorbic acid" should only be referred to when specifically discussing that chemical, otherwise use "vitamin C" or "ascorbate" ensure information is not being repeated NPOV: please try to ignore personal bias and focus intently on maintaining neutrality between the views of megadosers and non-megadosers Other: consider splitting any large sections to their own article keep article size down (without sacrificing any vital info) remove "see also" section - should be incorporated into the article proper See for further recommendations for improvement the comments made on the wikiproject notices
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Archives

Archive 1 (2001-2006)

More pseudoscience

"Alternative medicine" is double-speak. If it is not medicine, then it cannot be called medicine. I am changing "alternative medicine" to "alternatives to medicine" to emphasize that "orthomedicine" is not medicine. An encyclopedia is not a forum for pseudoscientists to use double-speak to make their quackery sound legitimate. —Preceding unsigned comment added by 24.126.151.171 (talk) 06:04, 16 March 2008 (UTC)

I don't fully understand why you chose to talk about this topic. Is it a response to something? Is it in the article anywhere?

You should really make new comments at the end of the discussion not the top as it is generally the accepted place to put new posts in the discussion page.

On the topic of your comment I can't see why anyone using the phrase "alternative medicine" could be accused of being a "pseudo-scientist". I study pharmacy and while that doesn't make me a doctor or a scientist in the strictist sense I am more than familiar with medicines.

All lectures touching on the subject refer to term "alternative medicine". It is generally the accepted usage of the term.

Maybe it's a matter of opinion but anyone working in health care that I have worked with has referred to it as alternative medicine, regardless of whether they are working in the more typical medical setting or the alternative field.

Maybe it is double-speak and I am giving more credit than is due and I will admit I have strong opinions against homeopathy (other branches to me have more credability), but I don't think it is designed to mislead.

I also don't think categorically denying it on a seemingly random talk page on Wikipedia will have any effect on the way people will use the term. Why not go to the Alternative medicine talk page as it will have more imact there. Medos ^{(talk • contribs)} 16:57, 16 March 2008 (UTC)

Pseudoscience

The evolutionary claims advanced by Mathhias Rath have no bearing in science whatsoever. Giving him an entire paragraph in this article lends him undue respectability.Can you imagine an article on the element mercury say, with a paragraph about the controversial doctor-x who theories that evolutionary deficiencies of it result in tennis elbow or some such nonsense. This article is replete with dubious nutrition as it is,without adding spurious evolutionary theories into the mix.Im removing the mathias paragraph for this reason.If people want to read about his crack pot theories they can look him up in his main article. Gerfinch 16:51, 21 June 2007 (UTC)

C Vitamin

Another indication (proof) of the myopia, insolence, and arrogance of the contributors from the Land of Intelligent Design: not only is this article incorrectly called 'Vitamin C' instead of 'C Vitamin' but THERE IS NO REDIRECT from 'C Vitamin' either. It's time people with this lack of savvy retired from Wiki. —The preceding unsigned comment was added by 62.1.114.104 (talk) 16:04, 19 March 2007 (UTC).

Just created the redirect now :P ...although, I'm not totally sure it was needed — Jack · talk · 05:29, Wednesday, 21 March 2007

And GOD spoke, and C, there was a vitamin? Sorry, the pun's so bad, had to get rid of it :) 199.74.98.127 04:03, 27 April 2007 (UTC)

About the opening sentence

The article begins with: "Vitamin C ... is an essential nutrient required in small amounts" When we read the rest of the article, we realize that what small means is actually the root of the debate on vitamin C (emphacized two sentences later). Small amounts, yes: smaller than protein, lipids, and sugars, yes. But as small as other vitamins? It would be partial (biased) to let this be suggested. The reference provided in the section "Natural mode of synthesis" [1] :

Milton, K. (1999) "Nutritional characteristics of wild primate foods: do the diets of our closest living relatives have lessons for us?" Nutrition. 1999 Jun;15(6):488-98.

which supports:

Most simians (higher primates who cannot produce vitamin C) consume the vitamin in amounts 10 to 20 times higher than that recommended by governments for humans.

Has its importance. If we accept that vitamin will mean "small amounts" in this case as well, without perceiving the very problem caused by this choice of words, we are not neutral. I would suggest something like the following: instead of:

Vitamin C or L-ascorbic acid is an essential nutrient required in small amounts in order to allow a range of essential metabolic reactions in animals and plants. Vitamin C is widely known as the vitamin that prevents scurvy in humans.[1][2][3] The joint US-Canadian Dietary Reference Intake recommends 90 milligrams per day and no more than 2 grams per day (2000 milligrams per day),[4] although the amount that humans require for optimum health is a matter of on-going debate.

I suggest:

Vitamin C or L-ascorbic acid is essential to allow a range of essential metabolic reactions in animals and plants. The unability to produce vitamin C (gulonolactone oxidase deficiency) is rare(ref avail.). It is shared by all great apes/primates/simians, including humans. The former consume vitamin C in amounts 10 to 20 times higher than what the latter consume. The amount that humans require is a matter of on-going debate. Vitamin C is most widely known as the vitamin, which, in small amounts, prevents scurvy.[1][2][3]

The following research, which also summarizes earlier results by others, poses well the problem that we are facing when speaking of vitamin C: Comp Biochem Physiol A Mol Integr Physiol. 2003 Sep;136(1):47-59. Micronutrient intakes of wild primates: are humans different? Milton K. Department of Environmental Science, Policy and Management, Division Insect Biology, University of California, Berkeley, CA 94720-3112, USA. kmilton@socrates.berkeley.edu Low micronutrient intake is implicated in a diversity of human health problems, ranging from problems associated with food insufficiency to those associated with food over-consumption. Humans are members of the order primates, suborder anthropoidea, and are most closely related to the great apes. Humans and apes are remarkably similar biologically. In the wild, apes and monkeys consume diets composed largely of plant foods, primarily the fruits and leaves of tropical forest trees and vines. Considerable evidence indicates that the ancestral line giving rise to humans (Homo spp.) was likewise strongly herbivorous (plant-eating). The wild plant parts consumed by apes and monkeys show moderate to high levels of many minerals and vitamins. The estimated daily intake of specific minerals, vitamin C and some other vitamins by wild primates is often quite high in comparison to intake levels of these same micronutrients recommended for humans. Are the high micronutrient intakes of wild primates simply a non-functional, unavoidable by-product of their strongly plant-based diets or might they actually be serving important as yet undetermined immunological or other beneficial functions? A better understanding of the basis for this apparent difference between humans and wild primates could help to clarify the range and proportions of micronutrients best suited for optimal human development, health and longevity. PMID: 14527629 [PubMed - indexed for MEDLINE] FULL TEXT: http://nature.berkeley.edu/miltonlab/pdfs/kmilton_micronutrient.pdf Any ideas on how to improve on fairness ? Pierre-Alain Gouanvic 07:12, 11 March 2007 (UTC)

Please see my addition to this Talk page, below, to see some comments on this issue. Antelan ^talk 22:36, 23 March 2007 (UTC)

Chemotherapy interaction

Moved uncited, oversimplified stmt here for discussion, improvement, and references. "Additonally, high doses of Vitamin C can reduce the effectiveness of chemotherapy as the Vitamin C neutralizes some of the free radicals generated by the chemotherapy intended to destroy malignant cells."--TheNautilus 04:14, 26 December 2006 (UTC)

Normally, vitamin C is used by the immune system to create free radicals in order to kill cancer cells. (See the book Ascorbate by Hickey) --Coppertwig 12:26, 20 February 2007 (UTC)

How many Vitamin C biosynthesis enzymes do humans have? Two or three?

The section "Vitamin C hypothesis" has this sentence: The fact that man possesses three of the four enzymes that animals employ to manufacture ascorbates in relatively large amounts, has led researchers such as Irwin Stone and Linus Pauling to hypothesize that... is this factually correct? As far as I know, most humans actually have two, instead of three, enzymes that play a part in the biosynthesis pathway. All humans lack l-gulonolactone oxidase due to the GULOP mutation. However humans who have only this mutation can still produce enough Vitamin C to stave off scurvy, i.e. at least 15mg. But 70% of humans also lack the lactonase enzyme that starts off the biosynthesis chain, and hence cannot produce any Vitamin C at all, thus being susceptible to scurvy. Source: http://centernet.okstate.edu/students/electives/nutrition/vitamin_c.cfm Is this correct? And if it is, shouldn't the page be edited to reflect that? Added by User:Shernren 13:54, 3 January 2007 (unsigned at the time)

These claims are very interesting. I have not seen it claimed anywhere else that around 15% of humans can still synthesise some vitamin C . As this paper is unsourced , unattributed and is in a Student area of the site, I would like to see other references before its added to the article. It could be someones original pet theory. Lumos3 14:01, 16 January 2007 (UTC)

This hypothesis appears to be untrue. See link. TimVickers 01:53, 12 March 2007 (UTC)

Contraindications Section

In the contraindications section, it states that deficiency of a particular enzyme can make a person prone to anemia, and that it can be exacerbated by consumption of things that induce oxidizing stress. It then goes on to imply that consumption of high doses of Vitamin C should be avoided for this reason in persons with this condition. This makes absolutely no sense. Vitamin C is a reducing agent, not an oxidizing agent. If anything, it should be used to treat the condition. --Uberhobo 01:26, 30 January 2007 (UTC)

Importance of Vitamin C to the Body?

I can't help but be curious, is there anything in this article that goes over this, even briefly? I know it prevents scurvy, and helps certain diseases or whatever, but other than that what does it do to help the human body? I'm in 10th grade doing a Biology paper, and one of the questions I had to answer was the importance of Vitamin C to the body, which isn't in my notes, and I can't find the section for it in my textbook. I could just write down that it prevents scurvy, but that's my answer to the next question 'what might result if we have a deficiency of Vitamin C?'. If I somehow missed it in the article, I'm sorry for that. But if I did, and it was there, I don't know how reliable this article could be if I couldn't even find it with the index or my skimming.

I'm not entirely sure of all the uses (there are a few), but by far the most important one is that Vitamin C is an essential cofactor required for the production of collagen, which happens to be the human body's most prevalent protein. Collagen is a hugely important structural component found in skin, bones, blood vessels, fibrous tissue, cartilage and hair. So, I guess you could say that without Vitamin C, we literally fall apart! It's in the article, but in a very obscure place; I'll try and sort that out - Jack · talk · 22:06, Monday, 19 February 2007

I have restored the Functions in the Body section which appears to have been deleted by a vandal (Ip 195.194.218.251) last 14th November and somehow gone unnoticed. Lumos3 22:37, 19 February 2007 (UTC)

Thanks for that, (despite the edit conflict :P) I was trying to sum that up but failing miserably. I changed the section header levels back to how they were, I feel it looks better this way - Jack · talk · 22:48, Monday, 19 February 2007

Should we renominate this for featured article?

I've been looking over this article, and its pretty comprehensive, well sourced and attractive. Should we try again for FA? It's been three years now since it failed! Must've changed loads. I think there could be some reference cleanup and there are a few loose {{fact}} tags, but apart from that I can't see any other major reasons why it would fail... If anyone sees any, could you outline them here and I'll help fix them and we can try again for FA. Woop! Jack · talk · 21:56, Monday, 19 February 2007

I've nominated this for a GA review, a crucial step the way - Jack · talk · 05:23, Wednesday, 21 February 2007

facts, not advice

Wikipedia is supposed to be a compendium of facts, not advice or instructions. This sentence needs to be deleted or modified: "Patients with a predispostion to form oxalate stones^{[citation needed]} or those on hemodialysis^[1][2] should avoid excess use of vitamin C.^{[citation needed]}". Besides, I disagree: for some such people, there may be a strong reason to take large amounts of vitamin C which might outweigh the concern expressed here. This sentence can be deleted or can be replaced with a sentence along the lines of "such-and-such institution recommends that ...". --Coppertwig 14:01, 22 February 2007 (UTC)

I see it's been changed to a NPOV statement. Thanks! --Coppertwig (talk) 14:16, 26 December 2007 (UTC)

racemic mixture?

The article currently claims, in the Biological significance section, Commercial vitamin C supplements contain a racemic mixture of both enantiomers of ascorbate, with both existing as a mix of ascorbic acid and mineral ascorbates. This statement seems to have been added by User:Jrockley on Feb. 19. I don't think it's true. I think vitamin C is normally synthesized as l-ascorbic acid and sold as such. It says later in the article that vitamin C is synthesized from glucose. Glucose is chiral, so that would tend to suggest that the vitamin C synthesized in that way would also be chiral. Small amounts of d-ascorbate being present (as claimed in the previous version) is different from a "racemic" mixture of equal amounts of both enantiomers. --Coppertwig 13:09, 26 February 2007 (UTC)

No, I don't have a source for that, and the source given doesn't state that. I just didn't think my statement through, and the source is probably an archaic reminant.

I think it's safe to assume that if Vitamin C is chemically produced, it will form equally in both forms, and if the undesirable form shows no biological activity, it'll be left in (see the thalidomide article) as that is cheaper. However, if the vitamin C is biologically produced (with enzymes) you're absolutely right, only the L form will be produced and sold. Probably best not to state either, without a source. Feel free to do as you will - Jack · talk · 14:21, Monday, 26 February 2007

Thanks. OK, I took out the part about racemic mixture. The footnote attached to that sentence (end of 2nd paragraph of Biological significance; link to "Vitamin C -- risk assessment") probably needs to be moved. It's probably a useful reference, but probably has little or nothing to do with the sentence it's attached to. Maybe to be moved to the bibliography, or attached to a different sentence. I'm not sure where to put it so I may leave it where it is -- maybe it supports various stuff said in that section. --Coppertwig 13:43, 27 February 2007 (UTC)

Prooxidant effects

Should this article contain some information on the pro-oxidant effects of vitamin C? Here is a review on this topic for a starting-point. TimVickers 20:07, 7 March 2007 (UTC)

I'd be interested to see what you write. Is it controversial? I thought vitamin C was an antioxidant, or can it be both? Perhaps you could draft it here, or just be WP:BOLD? — Jack · talk · 18:54, Thursday, 8 March 2007

Suggestions

Here are my minor suggestions:

• "This article describes its biological functions..." - an article mustn't contain such a sentence
• This reference: Milton, 1999 should be expanded should be referenced properly as I found it at the end of the Reference section

My main problem is that whether we should include dose related information in a medical article. BTW, a well-referenced, well-structured article. NCurse _work 21:23, 8 March 2007 (UTC)

Thanks :) I've implemented your minor change suggestions, and I've previously tried removing all of the dosage info here (to split into vitamin C megadosage), and here is where I added back a short summary. Do you think I re-added too much? — Jack · talk · 22:07, Thursday, 8 March 2007

Thank you, it seems to be good. Only one: It has been hypothosised that the vitamin can protect against: is it surely important? NCurse _work 16:33, 9 March 2007 (UTC)

I don't know, I thought it would be a good example of the suggestions made by megadosers. If you have a look at Vitamin_C_megadosage#Therapeutic_applications_of_high_doses, you'll see that...

It has been hypothesised that the vitamin can prevent and cure a wide range of common and/or lethal diseases, ranging from the common cold and cataracts to controversial statements involving it being a cure for AIDS SARS and bird flu. There have even been suggestions that vitamin C can cure lead poisoning and autism.

...is a very trimmed down version. I don't think it is particularly biased in anyway, and you could interpret it as "yes, us megadosers suggest that" or "ha! look at what those crazy megadosers are suggesting", and it is clearly important to the subject of the article. What would you include? Perhaps we could drop the last sentence — Jack · talk · 19:02, Friday, 9 March 2007

GA on hold

Please take care of the {{fact}} tags.--Rmky87 17:24, 9 March 2007 (UTC)

Done :) was that the only thing holding it back from GA status? — Jack · talk · 19:49, Friday, 9 March 2007

As far as I could see, yes.--Rmky87 05:15, 10 March 2007 (UTC)

You should move ref#10 to the end of the sentence.--Rmky87 14:03, 11 March 2007 (UTC)

GA Pass

I am going ahead and passing this article as the {{fact}}s have been taken care of. This article needs the gaps to be fixed, the external link cleanup to happen, and some repetitive information that needs to be dealt with. As soon as this happens, I would recommend nominating it for Featured Article status.--JEF 03:09, 13 March 2007 (UTC)

^_^ yay! Thankyou! I'll get right on it. Only, could you specify what you mean by "gaps"? — Jack · talk · 05:41, Monday, 12 March 2007

The blank spaces. Nothing too serious; it takes seconds.--JEF 03:09, 13 March 2007 (UTC)

I've taken a shot at removing possible whitespace causes here, although it doesn't seem to have made much difference to me. Blankspaces depend largely on screensize, font, textsize, your personal thumbnail choice etc. I see no spaces, besides unavoidable ones surrounding the food summary tables. Any information about the way others see the article would help. — Jack · talk · 06:35, Tuesday, 13 March 2007

I went ahead and did it myself. Look here to see how I did it.--JEF 00:32, 14 March 2007 (UTC)

Still looks the same to me. Yeah, I wouldn't have been able to fix that, I never saw any whitespace. But if it fixes it for some people, great! Thanks for that — Jack · talk · 11:47, Wednesday, 14 March 2007

Curing the Incurable: Vitamin C, Infectious Diseases, and Toxins

Dr. Thomas Levy's Curing the Incurable: Vitamin C, Infectious Diseases, and Toxins has been removed because it is already cited in the notes. (#39, for the moment) There is no need to repeat the book's name in the reference section. --BorgQueen 22:56, 16 March 2007 (UTC)

To shorten the length of the article

Hi colleagues! For now on, I'll try to edit parts of this article that seem too wordy. I'll write "wordy" each time I think I encounter occurences of such problems. I intend to meet the challenge of having a concise and dense article for such an immense topic. If I sacrifice too much (I'll be very cautious), do not hesitate to revert! Pierre-Alain Gouanvic 06:07, 18 March 2007 (UTC)

Thanks for your help. Although, I still think maintaining absolute neutrality is still your sticking point — Jack · talk · 03:36, Wednesday, 21 March 2007

Yes, and care must be taken to leave the necessary room for all points of views. Pierre-Alain Gouanvic 15:38, 21 March 2007 (UTC)

Questionable carnitine statement

"Two other vitamin C dependent enzymes are necessary for synthesis of carnitine."

I believe that only one vit. c - dependent enzyme is involved in carnitine synthesis (the first, I believe, to add an hydroxyl). This should be checked and the reference should be refreshed. Some open access documents must exist. Pierre-Alain Gouanvic 06:34, 18 March 2007 (UTC)

I was wrong: Am J Clin Nutr. 1991 Dec;54(6 Suppl):1147S-1152S.

Ascorbic acid and carnitine biosynthesis.

* Rebouche CJ.

It has been suggested that early features of scurvy (fatigue and weakness) may be attributed to carnitine deficiency. Ascorbate is a cofactor for two alpha-ketoglutarate-requiring dioxygenase reactions (epsilon-N-trimethyllysine hydroxylase and gamma-butyrobetaine hydroxylase) in the pathway of carnitine biosynthesis. Carnitine concentrations are variably low in some tissues of scorbutic guinea pigs. Ascorbic acid deficiency in guinea pigs resulted in decreased activity of hepatic gamma-butyrobetaine hydroxylase and renal but not hepatic epsilon-N-trimethyllsine hydroxylase when exogenous substrates were provided. It remains unclear whether vitamin C deficiency has a significant impact on the overall rate of carnitine synthesis from endogenous substrates. Nevertheless, results of studies of enzyme preparations and perfused liver in vitro and of scorbutic guinea pigs in vivo provide compelling evidence for participation of ascorbic acid in carnitine biosynthesis. PMID: 1962562

Pierre-Alain Gouanvic 18:43, 18 March 2007 (UTC)

Glycogen specifying

The vast majority of animals and plants are able to synthesize their own vitamin C, achieved through a sequence of four enzyme driven steps, which convert glucose to vitamin C.

It is important to specify that glycogen is actually the primary substrate. There is no direct glucose-to-ascorbate pathway. I encourage others to check it out. I'll find the references anyways. Pierre-Alain Gouanvic 06:40, 18 March 2007 (UTC)

Therapeutic uses section

Hi, I have moved the "Therapeutic applications of high doses" section away from the "vitamin c as a macronutrient" section because I understand nutritional and pharmacologic considerations to be different things. This change was reverted on the basis of neutrality. I don't perceive that this can be supported. Have I missed something? Pierre-Alain Gouanvic 06:18, 22 March 2007 (UTC)

About the title section "History of human understanding"

At first glance, I found this title to be a little redundant. A Web search shows that this phrase is used is similar contexts. I apologize for the hasty removal. Pierre-Alain Gouanvic 06:23, 22 March 2007 (UTC)

NPOV in first paragraph

The first paragraph is subtle, but induces bias for a person not already familiar with Vitamin C. A particularly precarious sequence is the following: The North American Dietary Reference Intake recommends 90 milligrams per day and no more than 2 grams per day (2000 milligrams per day).[6] Other related species sharing the same inability to produce vitamin C and requiring exogenous vitamin C consume 20 to 80 times this reference intake. The first statement is sourced and uncontroversial. The second sentence is unsourced, and needs support to be considered valid. From my experience with this material, I am confident someone will be able to find a peer-reviewed or otherwise acceptable source to back up this statement. Nevertheless, the juxtaposition of these two sentences leads the reader to question why the NADRI is 20 to 80x below what it is for other species. The inevitable conclusion is that the NADRI is set too low. This is a controversial point; as can be seen in Reference 24, there are thought to be evolutionary reasons behind the decreased need for vitamin C (involving uric acid). Glutathione and other molecules are also believe to fulfill similar antioxidant roles. As it stands, readers are not exposed to this additional information, and merely see that humans are getting 1/80th as much Vitamin C as do similar species. Therefore, I propose that either:

1. A sentence be added, with references, saying something along the lines of However, it has been hypothesized that uric acid and glutathione have taken on many of the roles of Vitamin C in humans; or,
2. The second sentence referenced above simply be removed as it is not a major contributory point of this article.

Any thoughts on the matter? --Antelan ^talk 22:29, 23 March 2007 (UTC)

The paragraph also states that "its uses and requirements are matters of on-going debate" . Either the debate around vitamin C is not mentioned or some allusion to its nature must be made. Vitamin C is the only vitamin where there is a continuing debate within the scientific community and I believe this needs to be said at the opening. Therefore some form of words which describe it are needed in order to give a hint of its nature. Either we point to higher consumption levels in non ascorbic acid synthesisers or we mention that most organisms produce it endogenously in what must be considered vast amounts. Lumos3 01:32, 24 March 2007 (UTC)

Those are actually two different ways of proffering the same point of view, not two halves of the issue. Because we mention that other non-ascorbic-acid synthesizers consume Vitamin C in higher amounts than humans, therefore we should also present the other half of the issue - that there is evidence pointing to compensatory mechanisms that account for our decreased requirements. Antelan ^talk 01:42, 24 March 2007 (UTC)

The controversy is exactly that. Megadose proponents say the primates rely on fragile systems of second best molecules like uric acid and an essential fruit diet to perform a range of body functions. The original mammalian model they evolved from on the other hand self metabolises the ascorbate molecule in what seem to us vast amounts. The metabolic pathways for the ascorbate molecule are still there within the primates waiting to be utilised. Megadose proponents say our systems are broken and have picked up a range of patches to get by. Skeptics believe this patched system is the optimum one. Some kind of summary of these different views needs to appear in the introduction. Lumos3 23:09, 24 March 2007 (UTC)

In addition, it is justified to mention the intake of primate relatives because, in fact, primate dosers and non-primate dosers (I'wont use the term megadosers, it is not neutral, just like the term vitamin is not neutral), both sides of the controversy, agree on the following (quoted from the authoritative Online Mendeleian Inheritance in Man, but also agreed upon by Pauling):

The mechanism whereby an organism loses a particular metabolic function which is of no use in a particular environment was discussed by King and Jukes (1969). The accumulation of random mutations in the gene for the relevant enzyme might be expected to destroy the functional capacity of the enzyme, most mutations being disruptive. If the enzyme is not required in the particular environment, the constraint of selection is removed. Primates and the guinea pig, by this hypothesis, have lost the capacity to synthesize ascorbic acid because of the adequacy of dietary intake.

So what is this adequate dietary intake? What's mentioned here. It might be seemingly biased to state the facts but... it isn't! (of course)

I would add that those "second best molecules" are not well identified yet; uric acid is one candidate, yes, but lipoprotein(a) is another (more convincing one to me); there also exists a view according to which viruses, more specifically retroviruses, might have played an active role in human evolution, i.e. that such pathogens, considered higher in species not producing ascorbate, accelerated mutation rates and the selection of new, favourable traits in humans (but I don't remember well, I should get the ref.).

To be straightforward, I don't think that non-primate dosers support their views (that we need no more than 200 mg per day) with such rationales. I don't think that they generally mention uric acid or lp(a). Really. I read a lot of this, and what I consistently found is references to pharmacokinetic studies (correctly analyzed elsewhere in the article) suggesting that more than 200 mg a day is just "expensive urine".

I thus find questionable to add urate or lp(a) or glutathione, etc, to support the views of non-primate dosers while those molecules were actually brought and discussed by primate dosers who, contrary to non-primate dosers, felt that they had to understand how primates can live without endogenous ascorbate (mammalian doses, if I may).

To avoid any appearances of non-NPOV and to enrich the article, I would summarize this quote above in order to appropriately introduce the sentence on primate intakes. Pierre-Alain Gouanvic 07:18, 25 March 2007 (UTC)

For greater neutrality, the single contested sentence could just be removed from the introduction, since the controversy is already alluded to in another introductory sentence. I think this is the preferable solution, since alluding to the controversy should be substantial enough for the intro paragraph; the conflicted viewpoints need not be elaborated until the body of the article. Antelan ^talk 17:35, 25 March 2007 (UTC)

What contested sentence? Pierre-Alain Gouanvic 03:24, 26 March 2007 (UTC)

The sentence around which our discussion has been revolving. Antelan ^talk 04:51, 26 March 2007 (UTC)

The sentence is now sourced. Please engage in the discussion. Pierre-Alain Gouanvic 05:23, 26 March 2007 (UTC)

The sentence has been sourced even since before I lodged my complaint. It's now double sourced. Read my discussion again; I'm concerned that it introduces bias; even supported sentences, when placed and worded in a certain way, can introduce POV. See WP:NPOV for more on that. See the discussion above for my suggestions on how to correct this. Antelan ^talk 18:04, 26 March 2007 (UTC)

Before going further. You say: "The sentence has been sourced even since before I lodged my complaint." But after reading, again, the discussion, I am puzzled: you said "The second sentence is unsourced, and needs support to be considered valid." Pierre-Alain Gouanvic 23:18, 27 March 2007 (UTC)

Yes, forgive me for the timeline: sources have been added since I began the discussion. However, my statment was as follows: From my experience with this material, I am confident someone will be able to find a peer-reviewed or otherwise acceptable source to back up this statement. Nevertheless... As you can see, I fully agreed from the outset that the statement would easily find a source to back it up - nevertheless, that is not even close to the point of my entire discussion. It's a strawman. Please read above and you'll see th