Talk:Vitamin C megadosage/Archive 1
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 |
General Comment on Page
I am distressed by how this page has evolved.
"despite a lack of "conclusive" scientific evidence". As if the word "conclusive" makes this statement NPOV!! Linus Pauling wrote "How to Live Longer and Feel Better". This books contains over 500 references to the scientific literature. These 500 references are a small fraction of the total scientific evidence supporting the benefits of vitamin C. A lack of scientific evidence!! Who is writing this??
It's been over 20 years since Pauling published his book. I read the vitamin literature carefully. I have never seen a point by point rebuttal of the arguments made in Pauling's book. I've never seen any persuasive, evidence-based rebuttal. In my opinion, much of what he said has never been persuasively disproven. This book initiated the extensive work on colds that I discuss below. Pauling was right on colds. I don't recommend betting against any of Pauling's assertions. shbrown 02:51, 22 September 2007 (UTC)
Many of the folks editing this page apparently have a narrow definition of science. Even double blind, placebo-controlled trials apparently aren't good enough. Both those for and against the effectiveness of vitamin C for fighting the common cold are referencing the same article. This Wikipedia article, in my opinion, is expressing the POV that vitamin C isn't much good for fighting colds. Here's a link to a well-referenced alternative view [1] Why shouldn't readers be encouraged to take between 2 and 20 g/day of vitamin C when they are fighting a cold and then decide for themselves? My family of four, all four grandparents, my sister-in-law... the list goes on all take between 4 and 20 g/day of vitamin C (low doses when healthy, higher when fighting a cold). Reading this article makes me feel like we're all kidding ourselves.
I am a practicing research scientist and I am blogging about vitamins. For full disclosure, I'm about to point you to my blog. "Megadoses" - whatever that means - of vitamin C have been proven to be an effective treatment to protect skin from the sun, and to treat a variety of other skin conditions. The vitamin C is formulated into skin creams. When applied to the skin, very high levels of vitamin C can be achieved in the skin. It is going to be very difficult to persuade me that elevating vitamin C levels in the skin by taking 2 to 10 g/day of vitamin C in divided doses is not equally effective. Here's my blog item on this subject [2], and here's a list of very recent scientific papers on the subject [3]
"Megadoses" of vitamin C (specifically between 0.5 and 1 g/day) is recommended by this authoritative source as the cure to scurvy [4]. Do the authors of this page seriously recommend that individuals suffering from scurvy should limit their intake to 60 mg/day? Do they doubt that vitamin C cures scurvy? After all, the vitamin C treatment for scurvy has not been confirmed by a modern, randomized, double-blind placebo controlled trial. —Preceding unsigned comment added by Shbrown (talk • contribs) 02:01, 22 September 2007 (UTC)
OK. Here's my signature. shbrown —Preceding signed but undated comment was added at 02:15, 22 September 2007 (UTC)
I'm reading through the discussion page and I can't believe the lack of logic. Ages back I wrote that the effectiveness of vitamin C for preventing colds is a function of dose. I provided a reference. Someone went to the reference and concluded that the reference didn't support the statement. Ugh!!
Vitamin C is necessary for proper immune function. Poor immunity is just one of the multitude of symptoms of scurvy. I'm sorry that I don't have a reference that explicitly says that people with scurvy are less resistant to cold viruses. If I dug around, I know I can make the case. If you'll grant me that, then it is a scientific fact that 10 mg/day of vitamin C is more effective than 5 mg/day of vitamin C for fighting colds. The multiple of double-blind, placebo controlled trials with vitamin C between 0.2 and 2 g/day proved that vitamin C reduces the duration and severity of colds above and beyond the RDA. So there it is. The effectiveness of vitamin C fighting colds is a function of dose. So what is going on here? How can scientists conclude that the increasing effectiveness of vitamin C for reducing the duration and severity of colds simply stops somewhere between 0.2 and 2 g/day? A legitimate issue at doses above 2 g/day is "do the benefits outweigh the side effects". Side effects are the reason that blinded trials can't be conducted with >2 g/day of vitamin C. Vitamin C typically causes obvious gastrointestinal symptoms at these doses. I don't even want to call these effects side effects. Many people like how large doses of vitamin C make their GI tract feel. Many people hate it. The multitude of other effects of vitamin C (beside reducing the duration and severity of colds) are different topics. It is not rational to believe that increasingly higher doses of vitamin C won't lead to increasing larger reductions in the duration and severity of colds. Thousands of "advocates" - maybe hundreds of thousands - testify to friends and family about the benefits of >2 g/day of vitamin C for colds. How long until the editors of the page consider this testimony to be scientific evidence? If epidemiological studies are science, then the testimony of thousands that >2 g/day doses of vitamin C work is also science. Do you folks really want to argue that scientists should simply disregard the clinical reports of the effectiveness of vitamin C for colds that are best represented by Robert Cathcart? [5] Cathcart's page is hard to read. Go here [6] shbrown 03:49, 22 September 2007 (UTC)
I flicked through the signatures on this discussion page. I'm not overwhelmed by the credentials of the editors. I recommend more respect for Wikipedia's philosophy that material should be rebutted in the article rather than removed so that readers can decide for themselves. In my opinion there's no need for every article to speak with a single "voice". There isn't a single voice on >100 mg/day doses of vitamin C. There are two voices - those that believe the science supporting taking supplements and those that remain sceptical despite the large body of science. Undoubtedly many of the sceptics have experimented with high doses of vitamin C and suffered side effects that made them unhappy, just as many of the "believers" take vitamin C supplements because they believe they feel benefits that outweigh any side effects. When I'm ready to write some reference material for the page, I'd appreciate it if it was left in the document. Go ahead and write a referenced sentence saying others disagree. I won't delete. And go ahead and reword my sentences (as I have a tendency towards serious POV). But don't delete the underlying assertion so long as it can be supported by the reference.
By the way, there is a single voice on >20 g single doses of vitamin C. >20 g single doses are often temporarily disabling and I doubt you'll find any vitamin C advocates denying this. shbrown 03:42, 22 September 2007 (UTC)
I see from the discussion section below that this guy [7] was driven away in frustration. Who benefits? I found his comments to be thoughtful and respectful.shbrown 03:55, 22 September 2007 (UTC)
- Well, basically it's because you don't understand how science (in this case medical science) and evidence works. (1) You produce a theory (e.g. Megadosage is good), (2) you test the theory through a trial, (3) you get the trial checked, (4) if your trial was well conducted, then it will be published in a respected medical journal, (5) if after publication your trial is not rebutted and other trials tend to support your thesis then the result may be accepted as true, (6) however later trial may still overturn your result.
- In short, if you can't get 'sources from published studies in respected medical journals (simple references are not enough)supporting Vitamin C megadosage then it essentially is scientifically meaningless. i.e. there is no evidence to support it. 221.133.86.7 (talk) 12:44, 12 December 2007 (UTC)
Merge discussion
- Merge - very large overlap, if not the same thing - Jack · talk · 03:11, Saturday, 24 February 2007
- Merge per Jack; also, "Dynamic flow" is poorly named; sounds as if it has nothing to do with vitamin C. "Megadosage" isn't the greatest name either: it's POV (implying that these dosages are huge -- compared to what?) but is acceptable. --Coppertwig 17:26, 25 February 2007 (UTC)
I went ahead and merged, as there were no objections — Jack · talk · 22:22, Wednesday, 14 March 2007
Can I...
Call bullshit on much of this article? It contains little criticism of megadose and couches the little that is presented in phrases like "possible, but unproven," etc. Why, prithee, is it not standard medical practice if there is so little debate surrounding it?
- Because, as the article explains, it costs about $200,000,000 to get regulatory approval for new treatments and this cost cannot be recovered under the current pharmaceutical patent regime. It's like the difference between Wikipedia and proprietary encyclopaedias. user: Colonel Warden 2 March 2007
Seconded. This looks a lot like other articles that have fallen into the orbit of the supplements business so I'd advise extreme caution and possibly a hefty (but less than the RDA, obviously) pinch of salt. The $200,000,000 statement appears to be unsourced, and furthermore the bearing of this upon research into vitamin C isn't explicitly stated. This technique of hand-waving and throwing about facts that don't quite add up to an argument has often been used by supplement advocates to excuse the lack of literature to back their claims, whilst snidely implying that those who disagree with them are drug company shills. See also: Patrick Holford discussion page.
- So moved. Those interested in keeping the unsourced claims should make efforts to source them. As per WP:NPOV, It is inappropriate to have an article explaining why evidence supports one view, but omitting such explanation in support of alternative views. This article is pretty light on evidence as is, but it certainly omits the opposing, and conventionally accepted, view. Antelan talk 22:06, 23 March 2007 (UTC)
- I created this article by splitting off all to NPOV material from Vitamin C, thereby "cleansing" a potential FA. The dregs will obviously produce a very biased article. But it isn't totally biased, it does have info on the adverse effects, and a bit of POV-cleanup could easily fix it — Jack · talk · 22:42, Sunday, 25 March 2007
I have added a citation from an academic source for the cost to launch of a new drug being $800,000,000. Lumos3 00:32, 26 March 2007 (UTC)
Where is the criticism section? As I understand it this article does accurately represent the consensus view of the medical establishment. Gantlord 15:29, 25 June 2007 (UTC)
Potential harmful effects
I renamed the section and removed the introductory paragraph which was unreferenced and purely POV. Antelan talk 18:11, 26 March 2007 (UTC)
Common Cold
I have a lot of problems with some of the conclusions drawn from this section. I'm going to look more closely into the evidence before I edit, but I feel that there are a quite a few unsound statements. First, the page contradicts itself, "The trials show that vitamin C reduces the duration and severity of colds but not the frequency." then goes on to state, "The studies provide ample justification for businesses to encourage their employees to take 1 to 2 g/day during the cold season to improve workplace productivity and reduce sick days.". The section clearly states that vitamin C reduces duration and severity (which I also feel is dubious at best, but I'll let it be for now), then says to use it as a prophylactic, a direct contradiction of an earlier statement. I'm going to re-read the Cochrane review conclusions in general, because I don't feel that this section represents the evidence. The last paragraph of this section are particularly troublesome as each statement seems ungrounded. N313m 02:06, 24 May 2007 (UTC)
Disputed Neutrality & Factuality Tag
The POV bias is obvious, but the factual inaccuracies are a cause of greater concern. I changed the most egregious that I found, but I'm no expert on the subject; this article needs to be examined and at least partially rewritten by someone neutral and knowledgeable.
- I believe I have fixed all the problems below. I'm not an expert but it didn't look like one would show up any time soon. I've removed the POV tag. Pocopocopocopoco 23:49, 22 July 2007 (UTC)
Intro Paragraph
(1a) There is a strong advocacy movement for large doses of vitamin C, despite not all purported benefits being supported by the established medical community.
This implies that some purported benefits are supported by the established medical community; as far as I can tell, this isn't true except in very rare instances.
(1b) Some qualified doctors practise orthomolecular medicine.
(1c) There exists an extensive and growing scientific literature critical of governmental agency dose recommendations.
These three sentences aren't inherently POV, but there is no mention in the intro paragraph of any negative aspect of vitamin C megadosages, save the second half of sentence '1a'.
'Advocacy Arguments' Paragraph
(2a) In summary, advocates argue that the biological halflife for vitamin C is quite short — about 30 minutes in blood plasma, a fact which National Institutes of Health (NIH) and IM researchers have failed to recognize.
This is vague: is the half-life actually 30 minutes, or is this just what some advocates believe? Why has the NIH failed to "recognize" this fact, and what exactly does that mean?
(2b) The established RDA is one that will prevent the onset of scurvy and is not necessarily the most optimal dosage; it's considerably less than the body-weight equivalent of what other mammals synthesize for themselves even when in good health.
Was the RDA based solely on scurvy-prevention? This seems unlikely. Also, there is no source given for the 'other mammals' info, and one wonders if this is even relevant since humans (unlike almost every other creature) cannot internally synthesize vitamin C.
Sources Falsely Surmized
(3a) A recent 55-study review[8] found little positive effect of a vitamin C intake on the common cold at low doses, but indication of prophylaxis benefits at higher doses especially where the subjects were in stressful situations.
It didn't have an effect "especially" with high-stress situations, it had an effect "exclusively" in those situations. Additionally, the source says, "great caution should be exercised in generalizing from this finding, which is based mainly on marathon runners." The overall conclusion was, "The lack of effect of prophylactic vitamin C supplementation on the incidence of common cold in normal populations throws doubt on the utility of this wide practice."
(3b) The data indicate that there is a normal dose-response relationship. Vitamin C is more effective the higher the dose.[9]
This isn't necessarily untrue, but it's certainly a misleading way of interpreting what was written. The report actually says, "In most cases, it appears that while the most important and dramatic preventive effects of vitamin C supplementation will be experienced by individuals with low vitamin C intakes, those with average daily consumption from foods may also benefit from supplemental levels." Note also how a hypothetical ("may") is changed to a definite ("is"). Also, the cautionary note is excluded from this article: "This same panel also cautioned that taking more than 1000mg of vitamin C daily could have adverse effects."
(3c) There is also evidence that vitamin C is useful in preventing lead poisoning, possibly helping to chelate the toxic heavy metal from the body.[10]
The source cited here was published in 1938.
(3d) In 2006 the Canadian Medical Association Journal published in vivo research that demonstrated that intravenous vitamin C can subdue advanced-stage cancer.[11]
The study actually says: "The cases reported here do not prove that vitamin C induced the favourable outcomes observed. These patients received other alternative medicine therapies...Accretion of more cases meeting NCI Best Case Series guidelines may indicate whether vitamin C or other factors contribute to such remissions. "
(3f) In January 2007 the US Food and Drug Administration approved a new trial of intravenous vitamin C as a cancer treatment.[12]
That's true, but from the same article: "Earlier studies conducted with vitamin C supplements administered orally did not demonstrate a clinical benefit to cancer patients." (emphasis mine).
(3g) As discussed previously, vitamin C exhibits remarkably low toxicity. The LD50 (the dose that will kill 50% of a population) is generally accepted to be 11900 milligrams per kilogram[13]
Yes, yes it is...in RAT populations!! Though I've since corrected the sentence, the original author neglected to mention this very crucial 'detail'. It is less than 1/3 that amount per kg in mouse populations, indicating there isn't consistency between species; hence, extrapolating that figure to human populations is patently false.
Unsourced Statements
(4) "...evidence exists for its therapeutic role in a wide range of viral infections and for the treatment of snake bites."
Also, the entire 'autism' section is based on an single unsourced internet survey.
Author's Opinion
(5a) The studies provide ample justification for businesses to encourage their employees to take 1 to 2 g/day during the coldseason to improve workplace productivity and reduce sick days.
(5a) However, the effectiveness typically comes at the price of gastro-intestinal side effects. It is easy for physicians to minimize these side effects since they cause no lasting harm.
(5a) It is well worth the effort of identifying the small subset of individuals who can benefit from high daily doses (>10 g/day) of vitamin C without side effects and training them to regularly take 5 g/day...
(5a) Orthomolecular medicine and a minority of scientific opinion sees vitamin C as being a low cost and safe way to treat viral disease and to deal with a wide range of poisons.
Seriously, was this written by a vitamin C salesmen or something?
Conclusion
I think that's sufficient info to indicate that this article is wildly POV, to the point of being factually inaccurate. Again, these are just the occurrences that I noticed while researching the topic; I didn't thoroughly read each section, and I'm no expert in the field. I highly recommend that this article be rewritten by someone who is, and that that person exercise prudence in incorporating any of the current material.--Xiaphias 15:27, 29 June 2007 (UTC)
Fact Checking
This article contained a number of controversial claims that have been labelled as unsourced for quite a long time. I have removed them. There are also a substantial number of references to a "Vitamin C Foundation" website which violates WP:V criteria. In addition, there are a number of statements that were original research (see, WP:NOR.) Finally, some statement blatantly mis-quoted the citation. Articles on meta-analyses stating "little effect" were taken out of context to support high dosing, etc...
I have tried hard to improve the citation on this article, but would appreciate some collaboration in this effort.
Djma12 (talk) 02:22, 2 August 2007 (UTC)
- Intro
- Source #1 checks out.
- Source #2 does not corroborate the sentence it backs. It actually says that selectively cytotoxic therapeutic levels for cancer are far, far higher than the levels established even by source #1. In fact, these levels can only be achieved parenterally, not enterally.
- Source #3 does not entirely corroborate the sentence it backs. Specifically, it makes no claim about a "strong advocacy movement", although it does support the portion of the sentence indicating that there is no conclusive evidence in favor of megadosing.
- Source #4 is not exactly reliable (it even has a promo for the book it is reporting on), so the claim about "literature critical of gov't dosing recommendations" is not solidly backed by this source. The claim itself is probably true (although vague - there is more than one government in this world).
- Source #5 does not actually say that Vitamin C has been suggested to cause cancer growth. Instead, the source says that Vitamin C may cause as much damage as it prevents, and has not been demonstrated effective as an anti-cancer tool. Specifically, at the bottom of the article, there is a note saying that investigating whether Vitamin C causes cancer will be a subject of further investigation. The source is unrelated to the atherosclerosis claim.
- Source #6 does not support the atherosclerosis claim, but it does support the cancer claim. The atherosclerosis claim is completely unbacked a this point.
- Claimed therapeutic applications of high doses
- Source #7 does not corroborate the sentence that it backs. Also, it no longer exists at the listed address. It has moved to http://www.umm.edu/altmed/articles/vitamin-c-000339.htm .
- Common Cold
- Source #8 checks out.
- Source #9 is comes from "Supplementwatch", a group with vested interests. This same article makes such unsubstantiated claims as, "... be sure to increase your intake if you’re exposed to stress (physical or psychological) or infection (like a sick friend of family member)." Nevertheless, it does support the statement it is tagged onto (but a better source should be found).
- Sources #10 & #11 I am unable to verify right now, but the author (Hemilia) has certainly gone on record saying as much.
- Heart Disease
- Source #12 indicates that Pauling's unvalidated supplement has 4, not 3, components. (ascorbate, traexamic acid, lysine and nicotinic acid). Traexamic acid is a t-PA inhibitor, btw.
- I find that very, very disturbing... Djma12 (talk) 23:06, 3 August 2007 (UTC)
- Uhh, yeah, agreed. FWIW, I'm inferring that it's a misspelling of tranexamic acid, as is suggested by this site. If not, then I'm just wrong, but I don't think so. So basically this thing has a t-PA inhibitor as its active ingredient...Antelan talk 23:25, 3 August 2007 (UTC)
- Great... Maybe we can start marketting a sports drink containing doxorubicin. Djma12 (talk) 01:41, 5 August 2007 (UTC)
- Uhh, yeah, agreed. FWIW, I'm inferring that it's a misspelling of tranexamic acid, as is suggested by this site. If not, then I'm just wrong, but I don't think so. So basically this thing has a t-PA inhibitor as its active ingredient...Antelan talk 23:25, 3 August 2007 (UTC)
- Source #13 says that this hypothesis is Pauling's.
- Source #14 is used misleadingly. OMIM cites the very same Pauling paper. If you are familiar with OMIM, you will know already that it is a vast summary of much of what has been said about most things biological. It cannot reasonably be called a "discussion as a hypothesis by mainstream medicine", since no discussion takes place on the OMIM pages.
- In progress... (but taking a break now)
- Kudos for a very thorough job. So when should we start acting upon this? Djma12 (talk) 01:41, 5 August 2007 (UTC)
Despite the lack of evidence...
Editors should be very cautious when the argument from ignorance appears. This time, it was said that there was a lack of evidence of benefits from high vitamin C levels, which is a very serious claim, which could abrogate the article entirely. Not surprisingly, it was an outdated reference from QuackWatch. The FDA approved vitamin C as a last resort for cancer patients (see vitamin C page - Therapeutic uses). Does this mean that the FDA is kind enough to satisfy the last wills of some cancer sufferers? No, this means that when all options that the FDA approves have been exhausted, the FDA approves a new therapy. Based on the evidence that the FDA analyzed.
A recent debate took place in the Journal of the Canadian Medical Association, to which researchers associated to US health dept. participated. They said it was time to reevaluate Pauling's declarations. There were also some harsh remarks on the mayo clinic studies that constitute the references of the reference that was in this article. I ask: how come nobody saw that? How come nobody realized that this little bit of sentence was destroying the very validity of the article? Is WP about describing fallacies? Pierre-Alain Gouanvic 09:41, 2 August 2007 (UTC)
- Not to bandy in semantics, but this is actually fairly important. The FDA did not "approve a new therapy" with Vitamin C for cancer, it opened a trial. Furthermore, the source cited did not state whether this was a simple Phase I toxicity trial to determine safe dosages vs high Phase randomized trials to determine efficacy. To quote the source without knowledge of which Phase trial it is, in my opinion, specious at best and dishonest at worst. I have left the citation in for the moment but am considering amending it. Djma12 (talk) 12:10, 2 August 2007 (UTC)
- And again, the specifics are important here. The statement was "despite the lack of CONCLUSIVE scientific evidence", which is a categorically true statement. The trials supporting Vitamin C have been in vitro studies or case reports. All of the double blinded, randomized trials have not achieved statistical significance. Read over the argument from ignorance article again. It also applies to attributing success to a therapy simply because you believe it to be true. Djma12 (talk) 03:23, 3 August 2007 (UTC)
- From WP:V: ""Verifiable" in this context means that any reader should be able to check that material added to Wikipedia has already been published by a reliable source. Editors should provide a reliable source for quotations and for any material that is challenged or is likely to be challenged, or it may be removed." Claims about clinical trials are a Big Deal; because of the weight they are given in medicine, such claims need to be attributed (i.e., there are many people here who will challenge such a claim if no reliable source documents the claim). If such a claim cannot be corroborated by a source that is good enough to indicate which phase the trial is in, it really should be removed. Antelan talk 12:21, 2 August 2007 (UTC)
- From what I can see in the reference, there is a sufficient answer to the question:
- "The first phase will be to determine the optimal dose for the patients and to learn whether the treatment is safe and can be tolerated, Lis said. Additional studies over several years would be needed to demonstrate whether it is effective. "
- Djma12, I only referred in a talk page to a reference that is already in both articles about vitamin C. In that, I followed what seemed to be common sense. They're trying to determine the optimal dosage = they are trying to assess efficacy. Assuming that you have read the reference, I don't understand what both of you are trying to say.
- This adds to the much too frequent problem of editors refusing to discuss important questions (I know phase I, phase II, that's not minor but:), important questions such as, I repeat, how can editors begin an article on vitamin c megadoses by stating that there's no evidence of benefit from vitamin c megadoses ? This should be renamed "The vitamin C hoax". I'm serious. This is not even POV, if we have already accepted this premise.
- But now, the other much too frequent problem, and I quote: "specious at best and dishonest at worst". Who are you? What gives you the right to voice such "opinions"? You might find I'm not cautious and tell it to me. But this is, of course, bullying. This is my opinion. I really hope we could meet, you and me, and talk about that around a coffee or a tea. I wonder if you would express yourself in such terms. Personally, I would tell you what I just wrote. And I'd expect an answer. Pierre-Alain Gouanvic 13:14, 2 August 2007 (UTC)
- Please don't take my statement as personally directed as you. I was merely pointing out that whoever put in the original form of the citation did not use it in an appropriate manner to support the article statement. Djma12 (talk) 14:00, 2 August 2007 (UTC)
- Ah. I read your initial response again and again. I find it hard to interpret it this way. After seeing the general quality of the article, I decided not to work with editors who let so much bias and spin stay on the page. I probably have much to learn from you, some criticisms are valid, but I'm getting tired of those discussions which do not address important issues. Pierre-Alain Gouanvic 14:56, 2 August 2007 (UTC)
- If by bias, you mean requiring that statements have adequate and accurate citation, then critique gladly accepted. Djma12 (talk) 20:06, 2 August 2007 (UTC)
- Ah. I read your initial response again and again. I find it hard to interpret it this way. After seeing the general quality of the article, I decided not to work with editors who let so much bias and spin stay on the page. I probably have much to learn from you, some criticisms are valid, but I'm getting tired of those discussions which do not address important issues. Pierre-Alain Gouanvic 14:56, 2 August 2007 (UTC)
- This looks like a Phase I trial ("safe and can be tolerated"). Thanks for the update. Antelan talk 13:17, 2 August 2007 (UTC)
- If this is indeed a Phase I trial, they are only trying to determine what doses can be tolerated, and they are not trying to determine efficacy. The statement, "They're trying to determine the optimal dosage = they are trying to assess efficacy." is not true. In earlier phases, researchers are merely trying to determine if the substance is toxic. They are also trying to determine pharmacokinetic parameters (absorption, distribution, metabolism, excretion). It is not until the later phases of trials are they even looking at efficacy.N313m 14:17, 2 August 2007 (UTC)
- The quote says: "They're trying to determine the optimal dosage". I understood: optimal clinically, in relationship to cancer.
- "The first phase will be to determine the optimal dose for the patients and to learn whether the treatment is safe and can be tolerated, Lis said. Additional studies over several years would be needed to demonstrate whether it is effective. "
- But as I said above, I give up. This is a very bad quality article, terribly biased. I won't try to explain obvious things to the editors currently working on the page. Unwatch! Pierre-Alain Gouanvic 14:56, 2 August 2007 (UTC)
- Bad quality in what way Pierre? You call POV foul when the article simply moved more neutral? It was horribly biased as it was.N313m 02:51, 3 August 2007 (UTC)
- I've found the actual link to this study on the clinicaltrials.gov website, and it is indeed a Phase I trial. Antelan talk 15:14, 2 August 2007 (UTC)
- If this is indeed a Phase I trial, they are only trying to determine what doses can be tolerated, and they are not trying to determine efficacy. The statement, "They're trying to determine the optimal dosage = they are trying to assess efficacy." is not true. In earlier phases, researchers are merely trying to determine if the substance is toxic. They are also trying to determine pharmacokinetic parameters (absorption, distribution, metabolism, excretion). It is not until the later phases of trials are they even looking at efficacy.N313m 14:17, 2 August 2007 (UTC)
- Please don't take my statement as personally directed as you. I was merely pointing out that whoever put in the original form of the citation did not use it in an appropriate manner to support the article statement. Djma12 (talk) 14:00, 2 August 2007 (UTC)
- From WP:V: ""Verifiable" in this context means that any reader should be able to check that material added to Wikipedia has already been published by a reliable source. Editors should provide a reliable source for quotations and for any material that is challenged or is likely to be challenged, or it may be removed." Claims about clinical trials are a Big Deal; because of the weight they are given in medicine, such claims need to be attributed (i.e., there are many people here who will challenge such a claim if no reliable source documents the claim). If such a claim cannot be corroborated by a source that is good enough to indicate which phase the trial is in, it really should be removed. Antelan talk 12:21, 2 August 2007 (UTC)
Just a minor improvement
I saw that an editor recently tried to improve the readability of the lead section (first sentences). After a comparison, I realized that elements were lost in the process.
The new version has balance and uses a minimum of words. I think it's rather elegant, actually!
If readability can be improved even more without losing important elements, it will be great.
VERSION 1:
Vitamin C megadosage can describe the consumption of vitamin C in doses similar to what other higher primates species consume in the wild,[1] doses intended to correct hypoascorbemia (the inability to produce vitamin C, common to higher primates and a few other species)[2] or doses considered to have specific therapeutic effects.[3]
VERSION 2 (after editing for readability)
Vitamin C megadosage is the consupmtion of vitamin C in doses much larger than the RDA recommended value. Advocates state that these dosages are similar to what other higher primates species consume in the wild,[1] or doses theorized to have specific therapeutic effects.[2]
VERSION 3 (second attempt to improve readability)
Vitamin C megadosage is the consumption of vitamin C in doses which are well beyond the current Dietary Reference Intake, but are similar to the intake of other primates not producing vitamin C,[1] or higher, to attain concentrations reached by most other animals, who produce vitamin C.[2] High doses can also be used used in an attempt to obtain specific therapeutic effects[3][4]
As editors can see, in version 2, a reference is lost. This reference is important because it is one of the best, if not the best reference, on the topic of this article. Along with the reference that was lost came the reference on the Online Mendeleian Inheritance in Man database (OMIM) (National Library of Congress), about hypoascorbemia (this inability to produce vitamin C shared by Humans and primates). It quotes this best reference I mentioned. This is a second reason to keep the reference and the meaning that was lost in the second revision. Finally, it is important not to let suppose inadvertently that advocates have an opinion on what other primates consume in the wild (an indicator of what our common ancestor consume). The amount consumed by our primate cousins is known with certainty, it's a fact; what they advocate for is that we should do like our cousins and our simian ancestors. By the way, if the other editor who worked on this (or others) have a good idea about a way to say elegantly that advocates try to reproduce the intake that our ancestor consumed when, according to OMIM, the intake was high enough to do without endogenous synthesis, it would be even closer to what both experts (OMIM) and advocates say, at the same time. There's this notion that genetics is the basis of the modern megadoses movement (Cf Stone, Pauling, most others). Finally, replacing "considered to have specific therapeutic effects" by "theorized to have specific therapeutic effects" might be a subtle difference, but it gives the impression that we are only dealing with theories. As most of you know (but you can check Vitamin-C therapeutic uses), the weight of evidence is quite heavy, there are many diverse therapeutic effects, the problem is mostly with obtaining 1. large scale quality studies with 2. high, therapeutic doses and 3. valid physiological endpoints (blood levels, markers of oxidative stress, of enzymatic activities, etc). The word "theorize", on the contrary, leads the reader to suppose that we are dealing with ideas, hypotheses only. It is important that we respect the work of researchers, even if it is not the golden standard of trials (as we all know, the better the evidence, the more expensive it is (in terms of RCTs, at least), and even if large doses remain mostly untested these days. (speaking of which, you'll be interested by the new study on cancer I just added to "vitamin c-therapeutic uses").
I hope the info was useful.
Pierre-Alain Gouanvic 08:29, 4 August 2007 (UTC)
- I'd ask that the sources not be changed until I can finish evaluating each of them (the list is above - I'm up to about #16 or so). Therefore, I'm asking that you revert yourself to the previous version so that I can continue evaluating sources. However, if this is, by consensus, not possible, I'll continue evaluating the sources via a copy within my userspace. Antelan talk 08:41, 4 August 2007 (UTC)
- Can you put your message where it is supposed to appear (I'm not sure) because :
- (Thanks)
Oops!? The following is what I wanted to put before the message from Antelan (above), but there was an edit conflict (we were editing at the same time):
- See, the problem I have with Version 3 is merely a grammatical one -- it's a run on sentence. That happens every once in awhile in complex articles, but we definitely should not lead into an article with one. I agree with Pierre-Alain Gouanvic that the info on primate dosages (with full references) should be included near the intro. If I removed a source by accident, it should definitely go back in. For readability, I think it makes more sense to make the strict definition as the first sentence, the have the second sentence amend the first sentence to reflect what proponents advocate. Djma12 (talk) 14:02, 4 August 2007 (UTC)
- I tend to see "well above the RDA" as non-neutral. A comparison with the RDA in the opening is not neutral: neutrality imposes that we say what Vitamin C megadosage is (an attemp to reach concentrations reached by all other animals (1. Our Primate cousins; 2. Those which produce vit. C) and then say that it happens to be at least 10 times higher than the RDA. This might not look neutral, but those are facts. The RDA is an educated guess, but it still a guess. It belongs to the category of opinions. Advocacy starts when one decides to say that the anomaly with the civilized human might be significant.
- So:
- Vitamin C megadosage is the consumption of vitamin C in doses which are well beyond the current Dietary Reference Intake. Proponents advocate that this dose is similar to the intake of other primates not producing vitamin C,[1] and is required to attain concentrations reached by most other animals, who produce vitamin C.[2]
- There's a wide range of so-called megadoses, from what I call primate doses (2 to 6 grams) to what I call mammalian doses (calculations would be necessary, because it's delivered by the liver, not per os): 13 grams times x (x=increased availability), to "stressed mammalian doses" ("manyfold" times 13 grams times x), etc. You also have the hibernating turtle, which resists to ischemia-reoxygenation because of her record breaking levels of C in the brain. Solid research on this. Also see my addition about dehydroascorbate in stroke (PNAS 1998).
This is why I wrote in the first version megadoses "can be a, b, and/or c"( a= primates (NO endog. C); b=mammals (endoge. C); c=any therapeutic use, with high doses.
- The point in common between all so-called megadosers is that they think that genetics are not given enough weight. For them, vitamin C loss (GULO deficiency, this "public error of metabolism" (OMIM)) was a huge change in our evolution (which had a purpose at that time). Leaving the rainforests was another costly change, since the 2 to 6 grams of C became less accessible. And now, the terrible RDA! ;-)
- This is where we distinguish advocates from others: those who think that GULO loss is extremely significant and those who think that GULO loss was not so terrible. The hypothesis can be falisified. This article would become much more interesting if we could follow up this. Comparative biology. Sutdies on guinea pigs (hypoascorbemic) or the Shionogi rat vs other lab animals (non-hypoascorbemic) But I'll work on this separately, because I can't bear the general attitude towards the sick that I see here. I need to think more about the sick and less about those who don't think enough about the sick.
- So please contact me on my talk page if you wish to respond. This is an invitation to you (not to Antelan, who wrote on my talk page after I had said I had had enough of this!!!!!!!!).
- Pierre-Alain Gouanvic 05:54, 5 August 2007 (UTC)
Lead and autism
- I saw that many people are working hard on this article in order to improve neutrality. The reference about lead, which is from 1939 (as emphacized by one of the editors), above, can now be completed by other studies, that I put in the vitamin C article. You might like to update the info. - - There's nothing actually new about those studies on lead and ascorbate. I just had to run a Pubmed search. I think that part of the work of restoring neutrality involves researching the literature. - - I'll send you updates about autism too, because there's also some interesting research material on this and probably useful clinical data that caregivers might like to discuss with their doctor, even if large RCTs have never been conducted. See comments above. I'll check if other things were missed. - Pierre-Alain Gouanvic 09:03, 4 August 2007 (UTC) -
Vitamin C and cancer
- - Just to make sure it's not missed by editors: as I said above in another section: a new cancer research (clinical research) has been published and deserves close attention and mention in this article. I'm surprised that it wasn't reported until today. See the vitamin C article - therapeutic uses.
Pierre-Alain Gouanvic 09:03, 4 August 2007 (UTC)
- Unless Vitamin C megadosage advocates intend to use intravenous methods to administer multiple grams of Vitamin C to themselves, that article is not relevant. It's an enteral vs. parenteral-uptake issue. Antelan talk
- No. Too narrow view of the topic. Bowel tolerance varies enormously. Look on Wikipedia. 09:15, 4 August 2007 (UTC)
- Also, it's an uncontrolled study of fewer than 50 patients being given a nontoxic substance... It's not exactly newsworthy. Antelan talk 09:18, 4 August 2007 (UTC)
- You seem to forget the literature that exists on vitamin c in cancer. Don't worry, it's coming (I'll get this for you and other editors). More importantly, don't forget that we're dealing with pain and severe handicaps treated with vit C, that many, many, people are experiencing right now. Yes: pain, invalidity, extreme discomfort... Doctors and patients are very concerned about those things. I don't know exactly what you are concerned about, although I have some hypotheses. Hey wait: why don't you summarize this article in the terms you just used? "uncontrolled study of fewer than 50 patients being given a nontoxic substance... It's not exactly newsworthy". Why don't you tell the doctors what you think about the study? Perhaps they might realize you're right? Don't forget to tell the patients too! Pierre-Alain Gouanvic 04:34, 5 August 2007 (UTC)
- To quote: You seem to forget the literature that exists on vitamin c in cancer.
- Really? All I've seen are in vivo studies, a 3 patient case study (which the authors themselves do not hold claim towards efficacy), and a Phase I toxicity trial.
- Maybe this is academic to you Pierre, it isn't for me. Last week I had a kid whose parents decided to take him off of proven chemotherapeutics with low toxicity and good cure rates in order to first try some herbalist's concoction of vitamins. Articles like this one matter, because it impacts how people perceive care. As such, they should be rigorously and accurately cited, without exaggeration of claims that aren't founded by study.Djma12 (talk) 04:44, 5 August 2007 (UTC)
- To quote: All I've seen are in vivo studies, a 3 patient case study (which the authors themselves do not hold claim towards efficacy), and a Phase I toxicity trial.
- That's exactly what I'm saying.
- The problem you had with those parents was yours to handle. It is not wikipedia's job.
- It is not "academics" for me either, don't assume that, after what I just said about pain and invalidity. You have to (I say you HAVE to) know what the parents are talking about. They love their child. You have the ethical duty to understand what these "herbs" are and what the "vitamins" are. You HAVE to offer to discuss with them AND with the person you called and "herbalist" with his "concoctions of vitamins" and see if you're really dealing with an obscurantist, or a potential ally, for the childs' sake. Otherwise, what? God knows. Who will be responsible? The naive parents? Wikipedia? People like... me? The doctor who sees "concoctions" and quacks where he could see allies?
- You know that you have a degree of freedom that could allow such compromises, in situations like this one especially. You could monitor changes in the child, warn parents if things go out of hand, tell them if it's not the case too (or if the child gets better. You're aware that it's possible). You could offer vitamin C, based on the study i provided. I'm sure they would love it, the child especially. So they left? I'm sad for them and I wish them good luck. I hope you still can propose a compromise. Since they say they want to try "concoctions", as you say, first (not instead), they're probably longing to see both sides work together for their child. Hm. Give it a try. But then I remember that you said "All I've seen are in vivo studies, a 3 patient case study (which the authors themselves do not hold claim towards efficacy), and a Phase I toxicity trial."
- While in fact, if you read the study on the 3 in vivo cases you read:
- The cases reported here are of tumours confirmed by histopathologic examination to have poor prognosis but that instead had long clinical remissions. Most previous case reports lacked independent pathologic confirmation of the tumour and did not follow the NCI Best Case Series guidelines, which makes their interpretation difficult. Recent findings show that only high-dose intravenous, but not oral, vitamin C therapy results in very high plasma vitamin C concentrations (e.g., 14 000 µmol/L). At these concentrations, the vitamin is toxic to some cancer cells, possibly because at these concentrations the vitamin is a pro-drug for hydrogen peroxide formation in extracellular fluid. Accumulated data confer some degree of biological and clinical plausibility to the notion that high-dose intravenous vitamin C therapy may have anti-tumour effects in certain cancers.
- Please. "do not hold claim towards efficacy"? Is it how you'd summarize this? BTW, bowel tolerance doses, in patients with cancer, can be very, very high (cf Cathcart).
- Reference: Does Medical Education have a Levelling Effect on Students' Moral Reasoning? http://www.cmaj.ca/cgi/content/full/168/7/840 CMAJ • April 1, 2003; 168 (7)
- © 2003 Canadian Medical Association or its licensors
- Pierre-Alain Gouanvic 07:08, 5 August 2007 (UTC)
- The course you advocated (close management) is exactly the course we took. Legally, we are allowed to compel care in the case of a minor, but when that is invoked, the parents tend to disappear with the kid. In this instance, I am saddened that the parents want to wait to try unproven therapies until the child has a poor prognosis before trying something now that is proven to work.
- Oh, and if I "offer vitamin C, based on the study i provided", I probably would and should lose my license. Djma12 (talk) 13:56, 5 August 2007 (UTC)
- Let's discuss the issue at hand. Provide valid info for this article via reliable sources and we'll put it into the appropriate place. I trust that you are familiar with what does and does not constitute a study based upon which one can make valid medical claims. As I have noted before, Vitamin C megadosage is not the same as potential IV therapeutics, since megadosage cannot replicate the high blood concentrations that can be achieved with IV Vitamin C.Antelan talk 07:25, 5 August 2007 (UTC)
- Pierre, I would recommend that you review the Levels of Clinical Evidence at [14]. Not all evidence is equal. A large (1,000+) person blinded, randomized trial is Level I evidence. This is why we prescribe aspirin daily for heart health. A Case Study of 3 patients is Level IV evidence: worthy of further investigation but irresponsible to advocate treatment recommendations.Djma12 (talk) 13:56, 5 August 2007 (UTC)
Citations in the preliminary summary paragraph
Mind you, I haven't read everything in wikipedia about how articles should be constructed, but isn't the normal practise that we have an initial summary paragraph(s) in the beginning without citations, then the body of the article elaborates on that and provides the citations? Pocopocopocopoco 00:34, 5 August 2007 (UTC)
- I think that's a reasonable approach, and typical of Wikipedia articles. Since this is a contentious topic, let's be sure to confirm that these sentences actually summarize the article, and that those sentences are sourced, before we remove sources from the intro. Antelan talk 01:13, 5 August 2007 (UTC)
- What's wrong with citations in the introduction ? Many articles have them - they seem useful and do no harm. Rod57 (talk) 12:38, 30 March 2011 (UTC)
Stones
I have removed kidney stones from the introduction, a speculative problem about a limited population probably inadequately advised about their particular gut biology, biochemistry and diet about a specific kind of stone and where there are vitamin C benefits too. Stones are a recurring negative, *speculative* POV in medicine when they have been addressed before, inadequately followed up by "mainstream" tests, tests seemingly only directed at finding problems with a minor CHO compound load (grams) rather than (re)measuring general solutions or pounds of other sources. Vitamin C was generations ago noted to resolve *some* kinds of kidney stone forming tendencies on a urinary pH basis that anyone with such a visible sediment problem can demonstrate with a glass and a day. Whither the FDA / pharmaceutical / med school testers there?
Oxalate stone formation is currently associated with individuals that are deficient in oxalate consuming bacteria in the gut. (I would love to see exhaustive life histories on diet/nutrients and antibiotics here.) Several authors have long addressed the chemical basis of oxalate precipitation more generally in terms of hydration and solubilizing cofactors such as Mg, B6, B1, citrate. Cheap oxalate treatment with methylene blue noted in the 60s and documented in the 70s by urologists was the backup position for oxalate stone formers also on megadose vitamin C. There is also complicated discussion on calcium and phosphates. And rather than pick on a few grams of ascsorbate, lay off the more common (pound/day?) CHO compounds associated with stones, like sugar[15]. But the pharma rep probably doesn't know & wouldn't tell anyway.--TheNautilus 20:46, 8 August 2007 (UTC)
- It's a POV backed by evidence, as are most other legitimate POVs in medicine: "total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis." [16] (Published in the J Am Soc Nephrology by some Harvard-affiliated folks in 2004). Do you have a link to a more recent study that controverts this one? Antelan talk 21:10, 8 August 2007 (UTC)
- Hi, could you elaborate on the meaning of "seems to increase the risk... "? If we read the whole sentence, we see a discrepancy:
- "Magnesium intake decreases and total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis." This is consistent with what TheNautilus just said; his comments should be addressed in the context of the current discussion.
- It would be interesting to relate this use of "seems to" with the uncertainties in the assessment of the putative ascorbate-oxalate-stone formation connection, uncertainties which are evident in the ealier literature as well.
- In addition, if there is evidence that the putative kidney stone-ascorbate connection, which still belongs to the realm of hypotheses developped by clinical epidemiologists, would only apply to a "limited population" (I've read the same research), it would be irresponsible for WP editors to extrapolate.
- Would you like to analyse the literature so that we can say with certainty that "total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis" means that "vitamin C causes kidney stones", as you suggest? Right now, it seems to be a leap of faith.
- May I remind you that we, as a species, used to consume 2 to 6 grams of vitamin C a day, and that our cousins still do so?
- Pierre-Alain Gouanvic 20:59, 11 August 2007 (UTC)
- Do I hear a double standard Pierre? You posted as definitive a number of weak studies (by author's admission) on Vitamin C and sperm count and such, and now you are critical of an article because of the word "seems"? I'd take a large study with 14 years of follow-up over the weak 8-12 patient studies that you posted any day. Djma12 (talk) 21:04, 11 August 2007 (UTC)
- You may hear what you want to hear. I won't interfere with that. Please answer to what The Nautilus or I said. Please read why I'm saying that the use of the word "seems" deserves a close look (see above and below). Because of what I underlined, this is a different use of "might", "may", "seems to", "suggests that" or the like, from one can see in the study you're referring to (Improvement in human semen quality after oral supplementation of vitamin C.).
- Also, if you have criticisms about what I bring to WP, you should be more specific. You are well aware that throwing "double standard" in a discussion is not advisable, unless you are appointed as a judge.Pierre-Alain Gouanvic 22:20, 11 August 2007 (UTC)
- Do I hear a double standard Pierre? You posted as definitive a number of weak studies (by author's admission) on Vitamin C and sperm count and such, and now you are critical of an article because of the word "seems"? I'd take a large study with 14 years of follow-up over the weak 8-12 patient studies that you posted any day. Djma12 (talk) 21:04, 11 August 2007 (UTC)
- "Seems to" are words used by responsible scientists when reporting their results, to emphasize the element of uncertainty inherent in science. It doesn't mean, as you imply, that they're just making it up. It's about sources. Rather than attack the use of "seems to", could you provide a reliable source indicating that Vitamin C intake does not increase the risk of kidney stones? I'm fine with citing the source as "Research has found that Vitamin C seems to increase the risk of kidney stones." That's not a leap of faith, but a direct quote from a reliable source. Again, I don't think we need to overdo the kidney-stone thing; it's not a common side effect, by any means. But acting like it doesn't exist, when there are reliable sources indicating it does, isn't the right approach. MastCell Talk 21:05, 11 August 2007 (UTC)
- 1. Don't assume that I "imply that they're just making it up"
- 2. A response to me should address what I say. I quote:
- "Magnesium intake decreases and total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis." This is consistent with what TheNautilus just said; his comments should be addressed in the context of the current discussion.
- So, no, Mastcell, we're both aware that "responsible scientists" use "seems to", but if this is contrasted in the same sentence by "Magnesium intake decreases (...) the risk of symptomatic nephrolithiasis", I have to repeat to you that this is not, as you say, "to emphasize the element of uncertainty inherent in science." I won't lecture you as you do, but could you please read the discussions?
- 3. The burden of evidence remains on the side of those who want to extrapolate that "Vitamin C causes kidney stones" (instead of what follows:). We could state, rephrasing what you said, "may contribute to kidney stone formation in specific susceptible populations" and characterize the condition that they have that may make them susceptible to relatively significant oxalate stone formation in response to pharmacologic doses of vitamin C. This, I believe, would satisfy The Nautilus' request for neutrality, if it's done well.
- 4. As I said, it would be irresponsible not to say that this applies to a "limited population" (and we should characterize this population, and put the risk in context). I did not "indicat(e) that Vitamin C intake does not increase the risk of kidney stones".
- 5. Since there is an enormous difference between what I said and what you interpreted of what I said, and since this interpretation of yours presents me in a bad light, I ask you to take back this comment, so that we could continue our discussion.
- Pierre-Alain Gouanvic 22:20, 11 August 2007 (UTC)
- "Seems to" are words used by responsible scientists when reporting their results, to emphasize the element of uncertainty inherent in science. It doesn't mean, as you imply, that they're just making it up. It's about sources. Rather than attack the use of "seems to", could you provide a reliable source indicating that Vitamin C intake does not increase the risk of kidney stones? I'm fine with citing the source as "Research has found that Vitamin C seems to increase the risk of kidney stones." That's not a leap of faith, but a direct quote from a reliable source. Again, I don't think we need to overdo the kidney-stone thing; it's not a common side effect, by any means. But acting like it doesn't exist, when there are reliable sources indicating it does, isn't the right approach. MastCell Talk 21:05, 11 August 2007 (UTC)
- "Seems to" is a phrase that often finds a home in papers with unexpected findings. Given the outcomes of the prior experiments with very few patients, presumably these researchers had expected to see a protective effect from Vitamin C. If you are so concerned about the phrase "seems to", you could either read the article yourself to understand the methods and results that informed this conclusion, or you could email the corresponding author. This is the type of question that might justify such an email if you are actually uncertain of the intentions of their wording. To me, it seems a quibble. Antelan talk 14:15, 13 August 2007 (UTC)
I'm not really interested in a general debate about vitamin C, nor is that what the article talk page is for. There is a reliable source saying that high vitamin C intake "seems to increase" the risk of kidney stones. Your spin about "susceptible populations" is an inaccurate interjection for this source, as it studied normal men without a history of nephrolithiasis. This source meets WP:V; the burden, on Wikipedia, is on those wishing to include content to provide a reliable source for it. That has been done. Now, again, do you have another reliable source you'd like to add which claims that high vitamin C intake does not increase the risk of kidney stones? MastCell Talk 05:04, 13 August 2007 (UTC)
- "Your spin", "attack", "interjection", "not really interested in a general debate", (I am) "imply(ing) that they're just making it up".
- This is misrepresentation. I don't trust you. Anybody else in here?
- Pierre-Alain Gouanvic 08:02, 13 August 2007 (UTC)
- At this rate, your going to not trust every editor in Wikipedia. I suggest you assume some good faith and constructively engage in the editing process rather than engaging in bad faith smears. Shot info 02:28, 14 August 2007 (UTC)
- Your comment :""Your spin", "attack", "interjection", "not really interested in a general debate", (I am) "imply(ing) that they're just making it up". This is misrepresentation. I don't trust you." about Shot_info in unfair, rude and incorrect in my opinion. I have dealt with him on other articles and he listens to others, discuses and tries to follow policies properly. Please assume good faith in other editors. --CrohnieGalTalk 14:41, 14 August 2007 (UTC)
- It would go a long way if Pierre would address the actual relevant content issue: a reliable source has been provided indicating that high C intake seems to increase the risk of kidney stones. Is there another similarly reliable source that Pierre would like to produce in contradiction? All the bluster about trust, misrepresentation, etc is kind of beside the point, and obscures the only relevant, appropriate issue for discussion here: what is verifiable? MastCell Talk 17:35, 14 August 2007 (UTC)
- The ethics of communication dictate that you pay attention to what has been said before. Since you don't, and since you don't try to understand by yourselves the complicated story of the oxalate-kidney stone story, put your "seems to" in the article. I won't intervene. Goodbye, Antelan, Dr Djma12, Mastcell and Shot info. If this is Wikipedia, goodbye wikipedia. Pierre-Alain Gouanvic 04:59, 18 August 2007 (UTC)
- It would go a long way if Pierre would address the actual relevant content issue: a reliable source has been provided indicating that high C intake seems to increase the risk of kidney stones. Is there another similarly reliable source that Pierre would like to produce in contradiction? All the bluster about trust, misrepresentation, etc is kind of beside the point, and obscures the only relevant, appropriate issue for discussion here: what is verifiable? MastCell Talk 17:35, 14 August 2007 (UTC)
- I'm only asking you to engage, answer a good-faith question, and provide sources to back your assertion. I'm sorry you feel that's intolerable. MastCell Talk 18:43, 18 August 2007 (UTC)
Robert Cathcart and Bowl Tolerance articles are up for deletion
Interested parties should go to Wikipedia:Articles for deletion/Robert Cathcart and Wikipedia:Articles for deletion/Bowel tolerance and voice their opinion. Lumos3 22:45, 9 August 2007 (UTC)
Some mammals produce their own vitamin C therefore humans are suboptimal
I hear the above arguments made in favour of megadosage. From an evolutionary standpoint, the strong survive hence if producing your own vitamin C was optimal, the humans (or their ancestors) who could produce their own vitamin C would have displaced the ones that couldn't. Hence producing your own vitamin C is not more optimal. Is there any evidence to this effect that we could add it to the article? Pierre once made an edit reflecting that cosmic rays caused the human race to cease production of their own vitamin C. Is there any evidence to this effect? —The preceding unsigned comment was added by Pocopocopocopoco (talk • contribs).
- * Higher primates eat 2000 to 6000 milligrams of vitamin C a day. (references are in the article)
- * Except Humans, who are advised to eat 10 to 30 times less. (idem)
- * The vast majority of mammals produce even greater amounts (than 2000 to 6000 mg). (idem)
- * Nobody knows how and why Higher Primates don't ceased producing Vit. C. (idem)
- "Cosmic rays"? A common cause of mutation, so this explains very little. Whether I brought this or not, I think it would be unwise to forget that the main question is:
- * Why did the Higher Primates' common ancestor cease to produce vitamin C?
- * That is: why, amongst those ancestors, did individuals with this inborn error of metabolism fared better than those still producing vitamin C?
- * More troubling, why did all the other mammals (except guinea pigs and a few others) keep the Vitamin C machinery?
- Those are riddles, because there are many other species consuming lots of Vit. C, who still produce it in their liver, from glycogen.
- And finally,
- * Why should we eat 10 to 30 times less vit C than all other species with the same metabolic disease, including our cousins?
- These are important considerations, indeed, but cosmic rays, or some other DNA-damaging events, are probably not really issues here more than elsewhere. Random mutations also occur, environmental chemicals (even in the wild), can play a role, etc.
- There exists interesting hypotheses, that should be reviewed in the article.
- Pierre-Alain Gouanvic 08:43, 13 August 2007 (UTC)
- Humans also only have prehensile tails whereas most mammals and even other primates have full tails. Does that mean that we should be surgicially re-implanting them? The logical fallacy here is equating an association with causation. Until a link is made between observation and conclusion, this is just an interesting coincidence. Djma12 (talk) 13:48, 13 August 2007 (UTC)
- Illogical. Ridiculous. And then the jargon. Pierre-Alain Gouanvic 04:52, 18 August 2007 (UTC)
- Humans also only have prehensile tails whereas most mammals and even other primates have full tails. Does that mean that we should be surgicially re-implanting them? The logical fallacy here is equating an association with causation. Until a link is made between observation and conclusion, this is just an interesting coincidence. Djma12 (talk) 13:48, 13 August 2007 (UTC)
- "That is: why, amongst those ancestors, did individuals with this inborn error of metabolism fared better than those still producing vitamin C? "
- This is a common type of question ("Why did lacking ability X actually make our ancestor better?") that, when probed, is frequently answered ("Lacking the ability X happened, by statistical chance, to come in an individual who had unrelated ability Y. Possessing ability Y was such an advantage that even lacking ability X, this ancestor survived.") Ability X may be the ability to synthesize vitamin C; ability Y may have been something as simple and non-genetic as "being far away from the shore when the tsunami wiped out your competitors". I'm not offering that as the hypothesis in this situation, but there are a variety of different reasons that are well-known for traits becoming anchored in, and dominant in, a population. This is far afield of what needs to be discussed in this article, but it is part and parcel of evolutionary biology. Antelan talk 14:23, 13 August 2007 (UTC)
- Very interesting. Do you have reliable sources to support this? Provide them to other WP editors, because I won't listen anymore. Pierre-Alain Gouanvic 04:52, 18 August 2007 (UTC)
- This is a common type of question ("Why did lacking ability X actually make our ancestor better?") that, when probed, is frequently answered ("Lacking the ability X happened, by statistical chance, to come in an individual who had unrelated ability Y. Possessing ability Y was such an advantage that even lacking ability X, this ancestor survived.") Ability X may be the ability to synthesize vitamin C; ability Y may have been something as simple and non-genetic as "being far away from the shore when the tsunami wiped out your competitors". I'm not offering that as the hypothesis in this situation, but there are a variety of different reasons that are well-known for traits becoming anchored in, and dominant in, a population. This is far afield of what needs to be discussed in this article, but it is part and parcel of evolutionary biology. Antelan talk 14:23, 13 August 2007 (UTC)
- This notion can be found in Campbell's high school / college Biology text, probably any edition. Antelan talk 05:17, 18 August 2007 (UTC)
I know this is WP:OR but...
I believe taking 500mg of Vitamin C a day has pushed my iron levels too high. My ferritin use to be around 250 now it's 485. Anything above 300 is considered possible iron overload. Nothing really has changed other than the fact that I took that amount C for about a year. I commend those people who have added some neutrality to this article and not followed the old line that it's harmless even in macro nutrient dosages. Pocopocopocopoco 03:01, 18 August 2007 (UTC)
Further reading section
I removed a number of references there, but they've been restored. My reasoning is this: the publications from Pauling are one thing and are clearly relevant. But many of the other "further reading" links promote unproven claims/unverified research and thus violate WP:EL. If these books are reliable, encyclopedic sources, then they should be incorporated as sources into the article text. Just listing a number of books touting the benefits of Vitamin C doesn't add anything encyclopedic, and has a somewhat promotional flavor to it. Wikipedia isn't a substitute for google or Amazon, and unless there's a clear justification under WP:EL for including these specific references, I'd like to see them removed as unencyclopedic and promotional. MastCell Talk 18:24, 12 September 2007 (UTC)
- I agree. The policy per WP:EL on Undue weight is fairly clear. Djma12 (talk) 23:36, 12 September 2007 (UTC)
- MastCell, what specific claims in those books are you referring to? Please point out the specific violations of WP:EL of which you speak. I would like to look over the specific statements about Vitamin C dosage and effects in those books that you have a problem with. I found the reading list to be very useful, and have restored it. Using those books as sources for in-text citations is fine by me, but I don't see why they should be removed from the further reading section in the meantime. The books I've looked at so far from that list have in-depth referencing, and present facts based on the scientific studies they cite. I look forward to your analysis of the specific points that you believe are not up to par as further reading, from the books in that list. Healthwise 17:57, 13 September 2007 (UTC)
- It doesn't actually work that way. WP:EL states that "... it is not Wikipedia's purpose to include a comprehensive list of external links related to each topic. No page should be linked from a Wikipedia article unless its inclusion is justified." In other words, the onus is on you to indicate how these books add encyclopedic content, but yet should appear as external links and not cited sources in the text.
- Many books include long lists of references and cite scientific studies, but yet are not particularly reliable sources for an encyclopedia. The issue of undue weight is also relevant, as Djma12 pointed out. MastCell Talk 23:20, 13 September 2007 (UTC)
- There seems to be a confusion here between the external links policy WP:EL and the subject of the edit which is a list of further reading. It is desirable for every article to have pointers to published works so that the interested reader can take their research further. Published printed works require much collaboration and oversight to produce and consequently have a level of authority beyond a webpage. For that reason they are given more weight on Wikipedia. I would welcome inclusion of works critical of Vitamin C megadosage. I dont think a list of 10 books is exessive. Lumos3 21:10, 14 September 2007 (UTC)
- The external link guidelines are actually quite a bit more lenient than those for sources (including "further reading", which fall under the sourcing guidelines). I was giving them the benefit of the doubt by applying WP:EL instead. There still needs to be some justification of how these books are useful as further reading, and some attention to WP:WEIGHT. Adding more "critical" further reading isn't really the best approach; it would be better to look through these books and differentiate the encyclopedic, reliable ones from those that are not. MastCell Talk 21:20, 14 September 2007 (UTC)
I have restored Levy and Hickey to the reading list or the impression is given that nothing has been published since the 70s which is false. Both fill the reliability criteria. Lumos3 20:55, 18 September 2007 (UTC)
- Interesting... however, the Hickey book appears to be published by lulu (dot) com, a pay-to-publish/self-publishing press. Therefore, per WP:V and WP:RS, it fits the definition of self-published sources to be avoided ("Anyone can create a website or pay to have a book published, then claim to be an expert in a certain field. For that reason, self-published books... are largely not acceptable as sources.") I've therefore removed it. MastCell Talk 21:07, 18 September 2007 (UTC)
Pop culture
Here's a pop culture reference: In an episode of House this year (either episode 5 or 6, I can look it up), one of House's trainees faked a positive polio lab result in a patient, then poisoned that patient to make him look ill. He then reversed the poisoning with megadoses of Vitamin C, making it look as though the megadose had cured polio. He believed this would stimulate funding for megadose research, but House caught on to his ruse. It was the largest amount of popular culture I've ever seen dedicated to the Vitamin C megadosage movement. Antelan talk 18:40, 12 December 2007 (UTC)
Yes, I have seen it. I've been amazed, that the pop-culture even mentioned that such a therapy exists. I've been however disturbed by the pop culture make-up, that the patient went into seizures for "he ran out of Calcium because of C". This is far from the clinical experience published by Dr.Klenner, that the first, even rare, sign of lack of free Calcium ions (pulled out by the Vitamin C), is nose-bleeding, and that 1g calcium gluconate daily, IV, should be quite enough to prevent such an side-effect of megadosed C.
Frederick R. Klenner, M.D., F.C.C.P. Observations on the dose and administration of ascorbic acid when employed beyond the range of a vitamin in human pathology. J. App. Nutr., 23:61-88, 1971. http://www.orthomed.com/klenner.htm
Since the practitioners (Klenner, Cathcart,..), that have published these findings, mention the need for supplementary calcium quite often, together with complete methodology, I would really wonder, if the Doctor from House series, desperately seeking any chance to push a clinical research for the megascorbic therapy, just wasn't aware of that, being aware of the calcium depletion on the other hand.
As of pop-culture, there is usually some level of uncertainity and neutrality in Dr.House' episodes in order of spiritual themes and/or alternative medicine treatments, so I'm quite suspicious about the grosly anti-megascorbic way the story was made. Peter--87.197.110.119 (talk) 14:05, 26 November 2008 (UTC)
Disputed Neutrality... again
I nominated this article for further NPOV review because it includes large sections on purported benefits, and few sections or sources devoted to the fact that the mainstream scientific community rejects Vitamin C megadosage. The disclaimer in the introduction is insufficient and not informative enough to fulfill a NPOV requirement. —Preceding unsigned comment added by 158.104.202.155 (talk) 17:14, 20 January 2008 (UTC)
- I'm not clear as to why you think neutrality is still an issue. The article does present a purported benefit but follows up by showing that studies do not provide any evidence of that benefit. For example the common cold, it starts out by says that a 55 study review found little positive effect of megadosage. Pocopocopocopoco (talk) 03:17, 23 March 2008 (UTC)
- There is *limited* evidence, mostly dramatic case studies and clinical series, just not FDA Phase III (megabuck) efficacy tests to p=0.05.
- More like continued scientific misconduct & 60 years total evasion of institutional responsibility since Klenner's 1948 paper on viral pneumonia. 40 years after Pauling started, there are still *no* (published) mainstream tests of even Orthomolecular medicine's lowest recommendation for megadose vitamin C (Pauling's historical recommendation, 1-2 grams per hour at the first *hint*, not even 30 min later, of a cold), ca a total of 15-25 grams per day, much less Cathcart's or more modern bowel tolerance, do-it-yourself recommendations. This compares with dozens & decades of wasted mainstream "scientific tests" at 0.1 to 4 grams per day for established respiratory illness. Hemilä's re-analysis of published test data on orally administered vitamin C shows slight, increasing effects even at these lower megadose ranges, at even ~2 to 6 grams once per day & 8 grams just once. Still waiting for *literate* (like accurately read & test the hypothese & claims) "scientific" researchers.--TheNautilus (talk) 13:32, 2 April 2008 (UTC)
- I agree with TheNautilus. The dosage levels claimed to work by Pauling and others have never been scientifically tested, let alone tested and found not to work. Lumos3 (talk) 13:43, 2 April 2008 (UTC)
- Whether or not Pauling's dosage has ever been scientifically tested, the burden of proof is on the Vitamin C megadose proponents to back up their claims. Not only that, but there is no pleasing Vitamin C megadose advocates. For example you say 1-2 grams at the first hint of a cold TheNautilus. That is a standard of evidence Vitamin C megadose advocates know is impossible, which is why they set it. The magnitude also keeps increasing each year. First it is 1-2 grams, then it is 6-18 grams, and now the definition of "Vitamin C megadose" appears to be 15-25 grams. The dosage arbitrarily set by health nuts increases by the decade, and one day they will demand near lethal doses at 100 grams a day like Robinson tested on mice which was shown to slow cancer. Of course they will omit the fact that diet restriction (starvation) will do just as good a job if not better. See nutritionandcancer.org . 75.119.247.190 (talk) 20:04, 4 September 2010 (UTC)
- Quite apart from the fact that 100 grams per day does not even come remotely close to the lethal dose of ascorbic acid/vitamin C in humans, most of the comments above are simply besides the point. Editors' personal opinions (which, in the most part, are what this page seems mostly to be composed of) are completely irrelevant on WP, as described in WP:NOR and WP:NPOV.Vitaminman (talk) 21:30, 4 September 2010 (UTC)
- So, you admit that Vitamin C megadose advocates arbitrarily increase their standard of evidence to avoid scientific scrutiny? By the way, calorie restriction is a scientifically verified method of life extension, and is not a personal opinion. There is even a wikipedia page on it. It is also not a personal opinion proof was found by one of Pauling's associates that Vitamin C increased cancer incidence in rats in the dosages proscribed by Vitamin C megadosers. Yes, rats are not humans. Yes, correlation is not causation. But much has been said in these talk pages about scientific dogma and so-called institutional blindness. However, in order to satisfy the Vitamin C megadosers, you would have to conduct unethical medical trials with hundreds of grams (as you freely admit) in the total absence of other therapy (because they believe chemo supresses the immune system, despite evidence to the contrary). This is very much relevant to the point, as any source claiming to be a comprehensive test of Pauling or any other megadoser's hypothesis will be refused by megadosers as inadequate because megadosers have at the best an unscientific and at the worst an unethical standard of evidence. 75.119.247.190 (talk) 03:22, 5 September 2010 (UTC)
- Re. your first question, there certainly are - and always have been - a wide variety of opinions amongst scientists working in this area as to precisely how much ascorbic acid is necessary to treat the various diseases that are being researched in connection with it. However, it is precisely through such disagreements and counter assertions that science has, and always will, progress.
- So, you admit that Vitamin C megadose advocates arbitrarily increase their standard of evidence to avoid scientific scrutiny? By the way, calorie restriction is a scientifically verified method of life extension, and is not a personal opinion. There is even a wikipedia page on it. It is also not a personal opinion proof was found by one of Pauling's associates that Vitamin C increased cancer incidence in rats in the dosages proscribed by Vitamin C megadosers. Yes, rats are not humans. Yes, correlation is not causation. But much has been said in these talk pages about scientific dogma and so-called institutional blindness. However, in order to satisfy the Vitamin C megadosers, you would have to conduct unethical medical trials with hundreds of grams (as you freely admit) in the total absence of other therapy (because they believe chemo supresses the immune system, despite evidence to the contrary). This is very much relevant to the point, as any source claiming to be a comprehensive test of Pauling or any other megadoser's hypothesis will be refused by megadosers as inadequate because megadosers have at the best an unscientific and at the worst an unethical standard of evidence. 75.119.247.190 (talk) 03:22, 5 September 2010 (UTC)
- Quite apart from the fact that 100 grams per day does not even come remotely close to the lethal dose of ascorbic acid/vitamin C in humans, most of the comments above are simply besides the point. Editors' personal opinions (which, in the most part, are what this page seems mostly to be composed of) are completely irrelevant on WP, as described in WP:NOR and WP:NPOV.Vitaminman (talk) 21:30, 4 September 2010 (UTC)
- Whether or not Pauling's dosage has ever been scientifically tested, the burden of proof is on the Vitamin C megadose proponents to back up their claims. Not only that, but there is no pleasing Vitamin C megadose advocates. For example you say 1-2 grams at the first hint of a cold TheNautilus. That is a standard of evidence Vitamin C megadose advocates know is impossible, which is why they set it. The magnitude also keeps increasing each year. First it is 1-2 grams, then it is 6-18 grams, and now the definition of "Vitamin C megadose" appears to be 15-25 grams. The dosage arbitrarily set by health nuts increases by the decade, and one day they will demand near lethal doses at 100 grams a day like Robinson tested on mice which was shown to slow cancer. Of course they will omit the fact that diet restriction (starvation) will do just as good a job if not better. See nutritionandcancer.org . 75.119.247.190 (talk) 20:04, 4 September 2010 (UTC)
- Re. your claim about calorie restriction, whilst I am of course aware of this and other statements made by advocates of this practice, the fact remains that as yet there is no proof that this methodology will extend life in humans. In this respect, I note that one of its foremost proponents, Roy Walford, died at the age 79 of respiratory failure as a complication of amyotrophic lateral sclerosis.
- As regards the claim that ascorbic acid increases the incidence of cancer in rats, again, there is as yet no definitive scientific proof of this. Moreover, let's not forget that other studies have been done on rats that have made positive findings regarding the use of supplementary ascorbic acid in cancer. (EG [17] and [18]) Scientifically, therefore, any study making definitive claims that ascorbic acid increases the incidence of cancer in rats would still need to explain how other studies have come to entirely the opposite conclusion.
- Finally, as regards your claim that chemotherapy does not suppress the immune system, it might be worth your taking a closer look at some of the patient information leaflets for these drugs, as published by the drug manufacturers themselves. Not only do these mostly make specific mention of bone marrow suppression and neutropenia (EG GlaxoSmithKline's Hycamtin[19]) but they also admit to causing new, secondary, cancers (EG Bristol-Myers Squibb's Cytoxan[20]). In fact, it is all but impossible to find an example of a chemo drug that doesn't have these, and other, highly dangerous properties.Vitaminman (talk) 16:41, 5 September 2010 (UTC)
- I'm glad you brought up Roy Walford. Because it illustrates the broken logic of Vitamin C megadosers. Pauling lived until 93 they say, so Vitamin C must extend life. Meanwhile other people live less with x method, so their methods must be wrong. This is the crux of their entire argument, and easily demolished. Walford still did not die of heart disease, cancer or any of the number one killers of Western citizens. 79 is still a ripe old age, particularly for a male, and there's no reason to think calorie restriction causes ALS.
- Ironically, the same criticism megadosers make of scientific studies which do not support their hypothesis can be made for scientific studies which support their hypothesis. Namely, that the dosage is not enough. IV Vitamin C is a completely different issue than oral Vitamin C and produces far higher concentrations in the blood. Even megadosers admit that Vitamin C is all or nothing, eat x amount and anything less is as useless as the RDA except for scurvy. Therefore studies which conclude a quarter to half the lethal dose for rats lowers cancer must be taken with a grain of salt, since Vitamin C megadosers advocate Vitamin C as a preventative measure, not merely an emergency treatment. And they certainly do not advocate running around with an IV and a quarter of the lethal dose all the time. Oral vitamin C is nowhere near the blood concentration of Vitamin C for even the highest megadosers.
- I notice you completely sidestep the issue that denying chemo and other conventional treatment in most cases is unethical and therefore an unreasonable standard of evidence since megadosers will never be satisfied with any ethical scientific evidence. You also freely admit that the megadose hypothesis is untestable, because of a wide variety of opinions on what defines megadose. Therefore, there is nothing more to say except that if there is a wide variety of opinion, there is definitely no scientific consensus and an encyclopedia should not advocate controversal therapies. The standard of evidence for inclusion into an encyclopedia should also not depend on the existence of unethical scientific experiments, which you freely admit would be necessary to satisfy megadoser's demands.
- 19:10, 5 September 2010 (UTC) —Preceding unsigned comment added by 75.119.247.190 (talk)
So, Roy Walford lived to 79 and you describe this as a ripe old age whilst simultaneously inferring vitamin C couldn't possibly have helped Pauling to reach 93? And, moreover, without providing any scientific justification, you completely dismiss the possibility that calorie restriction could have caused ALS?
Your apparent blind faith in chemotherapy is equally irrational and unscientific, laughable, even, especially so given your accusations of sidestepping. In reality, despite your pretense to the contrary, there is an almost unlimited amount of evidence - even from the manufacturers themselves - that chemotherapy severely damages the immune system and causes secondary cancers. See the following, for example: Adriamycin, Alkeran, Amsa PD, Avastin, BiCNU, Camptosar, Cerubidine, Cytoxan, Ellence, Erbitux, Etopophos, Herceptin, Hycamtin, Idamycin, Ifex, Leukeran, Myleran, Navelbine, Taxol, Temodar, Thiotepa, Vinblastine, Vumon.
I also note that your personal opinions here are not supported by any reliably-sourced citations per WP:RS. As such, the fact that you couldn't even be bothered to try to reference your claims says it all, really... Vitaminman (talk) 21:23, 6 September 2010 (UTC)
- Come on, guys. Get a blog, step off the soapboxes, and read the talk page guidelines. Once you've started arguing heatedly about the validity of various approaches by comparing the lifespans of individual proponents, it's time to take a break. I'm ready to archive this thread, unless there is some actual article content matter to be discussed? MastCell Talk 06:05, 7 September 2010 (UTC)
- Which was actually my original point to our IP friend, namely, that most of the comments on this page are editors' personal opinions and are completely irrelevant on WP, as described in WP:NOR and WP:NPOV. Oh, how I wish that I wasn't so easily drawn into exchanges such as this... ;-) Vitaminman (talk) 08:10, 7 September 2010 (UTC)
- Reference spam is for the uneducated. Anyone can look up the flyers for these companies: do you think you are doing anyone a service? Furthermore, chemotherapy companies obviously state the most dangerous side effects of their treatments for obvious liability reasons. The issue is not chemotherapy, but your refusal to admit megadosers have an unethical standard of evidence in demanding withdrawal of conventional treatment. Chemotherapy while toxic, works. You use the word scientific without understanding the meaning. Hypothesis must be testable to go through the scientific method, and any which are not and claimed to be true are unscientific by definition. Megadosers can whine about how the scientific establishment is anti-Vitamin C, but it's their own fault for creating an untestable theory.75.119.247.190 (talk) 23:02, 9 September 2010 (UTC)
Copyediting/culling
I may be doing some serious copyediting here, and updating this with the current research. I want to present the timeline of scientific research, as it is pretty interesting. ImpIn | (t - c) 05:55, 27 June 2008 (UTC)
- I was glancing around for this vitamin C / early puberty link, currently cited to" AJ Giannini, AE Slaby. A speculation on oranges, puberty, marriage contracts and frozen foods. M.D.25(5):51-52,1981. I can't find anything. The closest study so far seems to be PMID 15036221, and it found an inverse correlation for pubic hair. It does cite another study which saw some connection between delayed puberty and low vitamin C intake and high polyunsaturated fat intake. Anyone know what M.D.25 is? II | (t - c) 17:51, 7 January 2009 (UTC)
Some material on high-dose arguments, interaction with cholesterol and blood vessels and genes to synthesize vitamin C was deleted from the Vitamin C article here. I note this in case some editors might want to put some of the material into this article, perhaps with additional references to back it up. ☺Coppertwig (talk) 17:53, 16 March 2009 (UTC)
- Section added. Lumos3 (talk) 11:06, 2 June 2009 (UTC)
Harri Hemila and problems in early reviews
It seems possibly misleading to say that Harri Hemila is just "a single researcher" [21]. She (confusion caused by a newspaper saying Harri is a she, but PLoS and Cochrane say Harri is a he [22]). He's published dozens of papers on antioxidants and vitamin C, was the second author on the recent Cochrane review on vitamin C and the common cold and the primary author on the recent Cochrane review on vitamin C and pneumonia (PMID 17253561). The fact that this is old and there's no retraction or correction would apparently add to its credibility; medicine, like all science, moves on once something has been established, and that's why it's not uncommon to see citations to decades-old work. Certainly he didn't "suggest" that there were errors, and we shouldn't cite him as "suggesting" what he stated strongly.
Although Hemila got his PhD in biochem in 1993 and MD in 1996, in 2006 he completed his dissertation on vitamin C and E for a PhD in "medicine". Here is a 2007 comment on the issue from him. It centers around a controversy over the placebo effect, something which has been hyped as much as vitamin C. II | (t - c) 08:22, 2 June 2009 (UTC)
- Well, how many researchers is Harri Hemila? :) Seriously, I'm not questioning her credentials. She's a researcher; she publishes, writes for Cochrane, works at a reputable university, etc. But she is one researcher. I think that if you have a series of meta-analyses on one hand, and a single researcher arguing that those analyses are flawed on the other, WP:WEIGHT is pretty clear about properly contextualizing that. The previous wording - that "major errors were documented" - is way too deterministic. I mean, you might as well say that every letter-to-the-editor in the NEJM "documents major errors" in their studies.
I don't think that the lack of a retraction should imply that research is still current. Papers are generally retracted only in cases of serious fraud, prior publication, or misconduct. Papers are not retracted once they are no longer relevant. Additionally, corrections apply only to serious misstatements of basic fact. Hemila's article expresses her view of the quality of data. That's part of academic give-and-take; it's not subject to a "correction" - otherwise, how could anyone ever have a real discussion about the quality of data? Again, my point is that the lack of a correction or retraction does not imply that Hemila was "right" and the meta-analyses were "wrong". It implies only that she did not commit fraud or make blatantly untrue statements of basic fact. Additionally, WP:MEDRS is fairly clear about the importance of using up-to-date information; hence the mention of the article's age.
Medicine may move on once something has been established, but that's a dangerous heuristic. Medicine also moves on once something has been discarded. Extending your logic, we could conclude that Rife microscopes work, because they were mentioned in Science in 1932 and never commented on since. The absence of comment is a bit difficult to interpret in and of itself. MastCell Talk 18:01, 2 June 2009 (UTC)
- Given that Hemila went on to become the Cochrane reviewer, and states in the letter that some of the people he accused found no problems with the analysis, it seems pretty fair to assume that the criticism has been received as solid. The cold Cochrane review (link) mentions this in a way that backs up what you're saying, though:
Anyway, this is definitely something which needs to be in the article. I don't really care that much how it is worded, but your comment that it was undue weight even in its diluted form provoked a response. II | (t - c) 18:32, 2 June 2009 (UTC)it has subsequently been claimed that the influential reviews by Chalmers 1975 and Dykes 1975 contain errors (Hemilä 1995; Hemilä 1996c; see pp. 36-45 in Hemilä 2006a). Furthermore, both Chalmers 1975 and Dykes 1975 placed considerable weight on the double-blind placebo-controlled trial carried out by Karlowski 1975a at the National Institutes of Health (NIH), which concluded that a statistically significant benefit of vitamin C supplementation was simply caused by the placebo effect. It has subsequently been argued that the placebo-explanation in the Karlowski paper (Karlowski 1975a; Karlowski 1975b; Karlowski 1975c) was not consistent with their own data (Chalmers 1996; Hemilä 1996a; Hemilä 1996d; see p. 21-5 in Hemilä 2006a).
- Given that Hemila went on to become the Cochrane reviewer, and states in the letter that some of the people he accused found no problems with the analysis, it seems pretty fair to assume that the criticism has been received as solid. The cold Cochrane review (link) mentions this in a way that backs up what you're saying, though:
Vitamin C supplements may raise cataract risk
This is a significant finding on a very large population over a long period of time, which significantly reduces the effect of confounding factors.
A study of women who were followed over an 8-year period has found that vitamin C supplementation, particularly in high dose and long duration, may increase the risk of age-related cataracts. The study included 24,593 women aged 49-83 years from the Swedish Mammography Cohort (follow-up from September 1997 to October 2005). The researchers used a self-administered questionnaire to collect information on dietary supplement use and lifestyle factors:
- Rautiainen S et al. Vitamin C supplements and the risk of age-related cataract: a population-based prospective cohort study in women. American Journal of Clinical Nutrition, Nov 18, 2009. PMID: 19923367
- "Conclusion: Our results indicate that the use of vitamin C supplements may be associated with higher risk of age-related cataract among women."
Brangifer (talk) 19:59, 26 December 2009 (UTC)
- Other well-designed studies have made completely contrary findings. EG: Comparative study of plasma ascorbic acid levels in senile cataract patients and in normal individuals; In vitro level of L-ascorbic acid radical in lenses of patients with senile or diabetic cataract--preliminary study; Prospective study showing that dietary vitamin C reduced the risk of age-related cataracts in a middle-aged Japanese population. As such, any attempt to draw any conclusion that vitamin C supplementation may increase the risk of age-related cataracts is unscientific unless it is able to definitively explain why other studies have come to an entirely different conclusion. Given therefore that this study does not definitively prove why other studies have come to an entirely different conclusion, we should not use it to claim that the use of vitamin C supplements may be associated with higher risk of age-related cataracts here. Vitaminman (talk) 22:28, 26 December 2009 (UTC)
- I don't see any reason to characterise this recent study as "unscientific", nor to compare it with three studies that, to be frank, addressed quite different questions. Take Comparative study of plasma ascorbic acid levels in senile cataract patients and in normal individuals and Prospective study showing that dietary vitamin C reduced the risk of age-related cataracts in a middle-aged Japanese population: both address "dietary vitamin C" and not "high dose and long duration" vitamin C supplementation. As for In vitro level of L-ascorbic acid radical in lenses of patients with senile or diabetic cataract--preliminary study: Unfortunately, I don't read Polish, but the abstract is sufficient to show the small sample size and the title alone shows that there's a comparison only between cataract types. The results of these studies do not at all contradict the Swedish Mammography Cohort findings. Keepcalmandcarryon (talk) 20:53, 30 December 2009 (UTC)
- To form a reliable scientific theory, one has to be able to definitively explain why previous studies have come to different conclusions. From what I can see, the Swedish study doesn't do this. Vitaminman (talk) 11:39, 31 December 2009 (UTC)
- I don't see any reason to characterise this recent study as "unscientific", nor to compare it with three studies that, to be frank, addressed quite different questions. Take Comparative study of plasma ascorbic acid levels in senile cataract patients and in normal individuals and Prospective study showing that dietary vitamin C reduced the risk of age-related cataracts in a middle-aged Japanese population: both address "dietary vitamin C" and not "high dose and long duration" vitamin C supplementation. As for In vitro level of L-ascorbic acid radical in lenses of patients with senile or diabetic cataract--preliminary study: Unfortunately, I don't read Polish, but the abstract is sufficient to show the small sample size and the title alone shows that there's a comparison only between cataract types. The results of these studies do not at all contradict the Swedish Mammography Cohort findings. Keepcalmandcarryon (talk) 20:53, 30 December 2009 (UTC)