Talk:Vitamin B6

Comment

"may be too technical for most readers to understand. Please help improve it to make it understandable to non-experts," This is silly - biology is just as complex as it needs to be for us to survive. Reminds me of the quote - "If our brain were simple enough for us to understand how they work - we would be to simple to understand that".

Please don't simplify - put in hyper-links to basic concepts but - biology is simply way more complex than what even most biologists realize. Most of what people think they 'know' is actually ungrounded narratives. Pretending that this page can explain vitamin B without understanding other bits would require "pulling the wool" or what I would call lying. It would also make it a useless web page - the Internet is already full of those. — Preceding unsigned comment added by 108.243.106.82 (talk) 00:35, 21 February 2019 (UTC)

Comment

Is this article still a stub? Dark Nexus 20:11, 1 January 2006 (UTC)

No.--DThomsen8 (talk) 23:16, 17 May 2015 (UTC)

Moving page Pyridoxine → Vitamin B6

• The redirect Vitamin B6 was originally listed on WP:RFD, but I realize now I should have listed this move here. The reason for the move: The page Pyridoxine actually talks about the two major forms of Vitamin B6, pyridoxine and pyridoxamine. However, pyridoxine is just one of these forms. Originally the page pyridoxamine was an exact duplicate of pyridoxine except for the image, but I redirected pyridoxamine to pyridoxine and added the pyridoxamine image to pyridoxine. However, since pyridoxine actually talks about both forms of Vitamin B6 it should be moved to Vtamin B6. What follows is the original discussion on WP:RFD. Exabyte (talk)­ 05:07, Oct 28, 2004 (UTC)

• Pyridoxine is just one form of Vitamin B6, and the content of both this article and Pyridoxamine talks about both forms (in fact they are exactly duplicate except for the image). The Pyridoxine article, because it is actually about both forms, should be moved to Vitamin B6 and either the image from Pyridoxamine should be included in the article and Pyridoxamine be changed to a redirect or the resulting redirect from the move should be converted to an article and Pyridoxamine changed to be specifically about pyridoxamine. Exabyte (talk)­ 20:26, Oct 24, 2004 (UTC)
• Would anyone like to comment on the proposed move before it is done? -- ALoan (Talk) 11:29, 10 Nov 2004 (UTC)
• Go for it--makes sense. (seems like there may be similar issues with Tocopherol/Vitamin E). Niteowlneils 18:19, 21 Nov 2004 (UTC)

After consensus was reached, page was moved from Pyrodoxine to Vitamin B6. COGDEN 18:59, Nov 24, 2004 (UTC)

Citations Needed

There are a load of claims about the benefits of B6, but a dearth of citations where these assertions are made and supported. Turly-burly 00:29, 10 May 2006 (UTC)

I see. The information is in the pages to which the external links point. Turly-burly 00:31, 10 May 2006 (UTC)

RE Pyridoxine - Aargh! I found some articles linking (in some unknown way) pyridoxine to psoriasis etc, but PubMed only has it in Italian and Russian! And Archives of Dermatology is subscription only. Seeing crap on the Internets (and not much, there's lots of herbal hippie stuff out there but not much published research, and most of that is from the 70's), we need a dermatologist or nutritionist with access to get some of these sources. Otherwise, the claims need to either be removed or changed to reflect that this is a belief strongly held amongst the Herbal Essances crowd :( but I'll keep looking Gaviidae 14:35, 27 November 2006 (UTC)

Another problem is that for mutliple claims, there are multiple sources, yet wikipedia doens't care for excessive sourcing. Apparently, those researching vitamins are only doing very specific studies-- recently bereaved homosexual men; non-smoking women between 20-45 taking birth control (reduces B6); pyridoxine and PMS; pyridoxine and babies with a rare genetic seizure disorder; pyridoxine and tardive dyskinesia in schizophrenics... first, should all these sources, if used, be instead in the B6 page instead of the Pyridoxine page (which makes similar claims)? Also PMID: 10859691 and others I wouldn't want to cite if I couldn't read the results myself. Gaviidae 15:00, 27 November 2006 (UTC)

It seems that a lot of the toxicity and overdose information is lifted directly from the Linus Pauling Institute web page. This needs to be properly cited to avoid plagiarism. 67.40.184.137 (talk) 22:51, 7 February 2008 (UTC)

A lot of the claims link to a howstuffworks.com page which seems to have been written by an N.D. (I guess that's a naturopathic doctor). The page cites no studies or actual research that I can find, and I think it should be removed and any claims that can only be found there or on similar pages gotten rid of. Not my area of knowledge, though. --Wintersweet (talk) 05:01, 28 December 2010 (UTC)

OK, here's a citation - or reference - that says that the P-5-P form of Vitamin B6 is bio-available as pyridoxine (darn - I was really hoping this would be the other way)...

Given that the bioavailability of pyridoxal 5’-phosphate requires hydrolysis of the phosphate group before absorption through the intestinal layer may occur, one can conclude that the bioavailability of vitamin B6 from pyridoxal 5’-phosphate will be lower than or at best similar to the bioavailability of pyridoxine.

from: The EFSA Journal (2008) 760, 1-13 -- Opinion on Pyridoxal 5’-phosphate as a source for vitamin B6 added for nutritional purposes in food supplements http://www.efsa.europa.eu/en/scdocs/doc/afc_ej760_pyridoxal_op_en,0.pdf?ssbinary=true

Questions

- What's the symbol or chemical formula for vitamin B6?

- What is the half-life for vitamin B6 ?

It appears the chemical formula is C8H11NO3. SpazKitty 16:55, 1 November 2006 (UTC)

- Shouldn't we talk about how B6 deficiency can be one cause of sideroblastic anemia? —Preceding unsigned comment added by 74.10.183.251 (talk) 01:48, 7 March 2009 (UTC)

- We should know more about excess levels by blood test? My wife had high levels of B6 that resulted in chronic fatigue, reducing B6 eliminated the problem. Our neurologist recommended reduction of B6 which we will discuss with a dietician soon. — Preceding unsigned comment added by 108.49.176.140 (talk) 22:02, 7 November 2017 (UTC)

Rating

Upgraded it to start. TerriG149.155.96.5 19:22, 27 October 2006 (UTC)

Set-up

Why, under history, does it only have one sentence about history, and then goes on to talk about chemical composition? But I worry about messing with this page too much. Gaviidae 15:04, 27 November 2006 (UTC)

Name

Shouldn't the name of this article be Vitamin B₆? This article makes use of subscript with a template. Perhaps we can use this:

{{downsize|title={{mp|Vitamin B|6}}}}

DanPMK 21:07, 22 February 2007 (UTC)

Dreaming

Carl Pfeiffer knew (by the mid-1970's, at the latest) that pyridoxine increased dream recall. He recommended that certain of his patients (those suspected of what he called histadelia) take increasing amounts of pyridoxine each day until the dreams became unpleasant, and then cut back a little. Perhaps orthomolecular.org may have a citation. Unfree (talk) 02:39, 14 February 2008 (UTC)

Functions vs. Metabolic Functions

These sections should be combined due to numerous redundancies. —Preceding unsigned comment added by 70.126.59.104 (talk) 20:37, 17 December 2008 (UTC)

FDA: pyradoxamine = drug, not dietary supplement?

Would someone knowledgeable add the appropriate info from here... http://aahf.nonprofitsoapbox.com/index.php?option=com_content&task=view&id=677&Itemid= 68.83.72.162 (talk) 13:09, 26 February 2009 (UTC)

I have added the information to pyridoxamine, rather than here, since it is specific only to that compound, and not to any of the other forms of vitamin B6. -- Ed (Edgar181) 14:48, 26 February 2009 (UTC)

Does the FDA define the English language? — Preceding unsigned comment added by 108.243.106.82 (talk) 00:39, 21 February 2019 (UTC)

For Future Experiment

Sections seems confused and useless, should be removed —Preceding unsigned comment added by 128.32.8.99 (talk) 23:43, 8 July 2009 (UTC)

Gene expression section is confused and useless as well. —Preceding unsigned comment added by 72.183.255.245 (talk) 15:37, 21 January 2010 (UTC)

Bite Reduction

In the Army, we used Vitamin B6 to reduce bug bites (yes, it works). Has there ever been a study about this? 138.162.128.55 (talk) 17:21, 15 July 2009 (UTC)

no idea —Preceding unsigned comment added by 122.168.223.194 (talk) 11:35, 26 August 2009 (UTC)

Reference template

An unskilled editor in this subject so far as I'm concerned since I've never seen him editing nutritional articles, which is just hounding my edits, decided to template the article disputing the whole content as questionable and desperately requiring further reference (beyond it's currently 25). Please just tag the article section you see as most problematic so we can work on the article gradually instead of leaving this ugly template in the whole article.--Nutriveg (talk) 14:32, 22 May 2010 (UTC)

It doesn't take "skill" to see that half the article is completely and totally unreferenced, which is what the template signals. Also please refrain from further personal attacks against me. --ThaddeusB (talk) 15:01, 22 May 2010 (UTC)

The article has 25 references! If the problem is with a specific section tag those sections! "Not everything need actually be attributed" but surely don't have any skills on the issue of Vitamin B6 to distinguish what's obvious, you're just trying to create problems here!--Nutriveg (talk) 15:12, 22 May 2010 (UTC)

Please stop with the person attacks and assumption of bad faith. I will move it to specific sections as per your request. --ThaddeusB (talk) 15:14, 22 May 2010 (UTC)

P.S. More than half the references are in ONE section of the article, so the total number is a poor indication of how well referenced the article is. --ThaddeusB (talk) 15:23, 22 May 2010 (UTC)

"Not everything need actually be attributed" just for the sake of being referenced, if you're unskilled or unable to check the content just don't mess the article using unnecessary templates!--Nutriveg (talk) 15:28, 22 May 2010 (UTC)

Stop making assumptions about my skill and intentions. --ThaddeusB (talk) 15:29, 22 May 2010 (UTC)

P.S. If something isn't obvious to an "unskilled" reader, than it should be attributed. --ThaddeusB (talk) 15:33, 22 May 2010 (UTC)

You could have stopped my assumptions about your skills (from your edit history in nutritional issues) if you had already presented your qualifications in the area.

I didn't make any new assumption about your intentions, stop repeating yourself! I said your indiscriminate use of templates mess the article, that's a fact!--Nutriveg (talk) 15:46, 22 May 2010 (UTC)

About your PS: that's a complete false statement of yours: only "challenged or likely to be challenged (material need to) be attributed". Unskilled editors usually don't challenge what they don't know since they don't have scientific knowledge to contradict those statements. You made your point templating the article so now move on.--Nutriveg (talk) 15:46, 22 May 2010 (UTC)

I am perfectly capable of editing a wide variety of subjects (and have done so for a long time without incident). There is no requirement that someone be an expert in a given subject to edit Wikipedia, so please stop insisting there is. Also, if you are going to insist that the statements must be challenged before a source is required, consider them officially challenged. (As I already did implicitly by tagging the article as insufficiently sourced to begin with.) --ThaddeusB (talk) 21:03, 22 May 2010 (UTC)

So, as you're challenging it, do you support the removal of such sections if it remains unreferenced or do you have an alternative text, supported by sources, for such sections ?--Nutriveg (talk) 12:33, 25 May 2010 (UTC)

Acronyms

The chart at Vitamin B6#Dietary reference intakes makes use of acronyms that are not used elsewhere on the page. Could someone knowledgeable in this topic please create a legend for the chart? --Kraftlos (Talk | Contrib) 09:22, 23 January 2012 (UTC)

Dietary Reference Intake no longer a chart, and all acronyms explained.David notMD (talk) 02:56, 19 March 2016 (UTC)

Consider adding hypophosphatasia as a cause of elevated B6 levels.

Consider adding hypophosphatasia as a cause of elevated B6 levels.

http://www.oif.org/site/PageServer?pagename=Hypophosphatasia — Preceding unsigned comment added by Cherishhealth (talk • contribs) 04:20, 25 February 2015 (UTC)

Dietary Reference Intakes

I am creating the same format for DRIs for all B vitamins. That is a U.S.- based system that identifies Estimated Average Requirements (EARs), Recommended Dietary Allowances (RDAs), Adequate Intakes (AIs) if there is not enough information to establish EARs and RDAs, and Tolerable Upper Intake Levels (ULs). Another major regulatory agency that has established ULs is the European Food Safety Authority (EFSA). ULs for both are provided, as they often differ. If there is a UL (for some vitamins none has been determined) then rationale is covered in a Toxicity section. In addition to DRIs, the U.S. also established Daily Value, using it on food and dietary supplement labels as % DV. DVs were based on older RDAs and as of 2016 have never been updated to reflect the newer DRIs. Thus, often a product that has 100% DV and greater than 100% RDA. Examples given for each vitamin. What I have written can be improved. It lacks EFSA or other major country RDAs. It lacks an estimate of what percentages of people are deficient - although that is often covered in a separate section on deficiency and consequences of deficiency. I am creating this Subject in all of the Talk pages of the vitamin entries I have edited. Comments and improvements are welcome. David notMD (talk) 14:18, 2 March 2016 (UTC)

Changed section title to Dietary recommendations because Dietary Reference Intakes is used only in U.S. and Canada; added European information, with citations. David notMD (talk) 12:56, 31 August 2017 (UTC)

Duplicate references

References 15, 20 and 41 are identical. But I do not know how to do a multiple-cited ref. (I try and mess it up).David notMD (talk) 03:19, 19 March 2016 (UTC)

To whoever fixed this, thanks. David notMD (talk) 19:38, 4 April 2017 (UTC)

Prep for Good Article nomination

February 2021: Beginning process of improving article before nominating for Good Article. This will be my eighth vitamin upgraded to GA (if I succeed). David notMD (talk) 20:25, 5 February 2021 (UTC)

As much as possible, replaced refs that were more than 20 years old. And needed fewer refs for the foods listed in the Sources table. David notMD (talk) 11:27, 8 February 2021 (UTC)

Submitted for GA. David notMD (talk) 13:55, 5 June 2021 (UTC)

GA Review

This review is transcluded from Talk:Vitamin B6/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Esculenta (talk · contribs) 18:49, 3 August 2021 (UTC)

Hello, I will review this article for its GA-candidacy. I should have comments here within a few days. Esculenta (talk) 18:49, 3 August 2021 (UTC)

• the lead is too short and doesn’t do a good job of summarizing the article. See WP:LEAD for guidance.
• the article needs links all over the place for jargon terms that we shouldn't expect the reader to know. Examples: pyridine, co-factor, fatty acid, chlorophyll, E. coli, 1-deoxyxylulose-5-phosphate, macronutrient, enantiomer, transcription factor, desaturation, formyl, micronutrient, systemic inflammation, liver disease, rheumatoid arthritis, HIV, oral contraceptive, antivitamin, passive diffusion, mucosa, bioavailability
• some abbreviations like MPM and PLP are used before they are even defined
• why did György name this B6?
  • B vitamin number was chronological. See Vitamin#History. David notMD (talk) 19:08, 13 August 2021 (UTC)
• "characterization of pyridoxamine, the animated product of pyridoxine" aminated?
• "Vitamin B6 is found in the germ and aleurone layer of grains, and milling results in the reduction of this vitamin in white flour." this statement needs a citation; a comparison of vitamin amounts to milled flour would be a useful comparison, I think. Or, give typical % decrease after milling.
  • Table now includes whole wheat and white bread, and brown rice and white rice, as examples. David notMD (talk) 10:49, 24 August 2021 (UTC)
• it is claimed that fruits other than citrus are "among the richest sources" of B6, but the only example I see in the three-column list is raisins. My copy of Combs says "Milk, eggs and fruits contain relatively low concentrations of the vitamin."
  • Sources table revised. David notMD (talk) 18:01, 20 August 2021 (UTC)
• there’s a couple of citation needed tags in the "Absorption and excretion" subsection
  • Changed to Absorption, salvage and excretion, and referenced. David notMD (talk) 03:24, 22 August 2021 (UTC)
• the "Sources" tables are confusing to me: is the amount given beside the source the amount of one serving? If so, then /serving does not need to be part of the columns heading; if not, then it's not useful to add that in the column header, because we don't know what the serving size is! Also note that column 1 is formatted as "mg serving" while 2 and 3 are "mg/serving".
  • Sources table changed to mg/100g (to be in accord with other vitamin articles).David notMD (talk) 20:13, 18 August 2021 (UTC)

These items above are easily addressed. However, I think the article has a bigger issue with missing information. I used several sources to help me assess if WIAGA criteria 3 is met (3.Broad in its coverage: (a) it addresses the main aspects of the topic"). This included a more recent edition of the Combs textbook already used in the article, an introductory biochemistry textbook, an introductory nutrition textbook, and a search of review articles from pubmed, published in the last five years (i.e., WP:MEDRS compliant). Based on these sources, here's information I would expect to see in the article:

• should state that all B6 vitamins are derivatives of the 3-hydroxy-2-methylpyridine structure; a labeled diagram might be helpful readers to visualize the numbered positions on the ring and side chain
• article should state that pyridoxine or pyridoxol (PN), pyridoxal (PL) and pyridoxamine (PM), have, respectively, alcohol, aldehyde and amine group in the 4-position – i.e., stating clearly the chemical differences between the related vitamers
• should say that PLP is attached to the apoenzyme by a Schiff base (aldimine) linkage (–N=CH–) formed through condensation of the 4-carbonyl group with the ε-amino group of specific lysine residues. No mention of the biochemistry of PLP binding to protein via its Schiff base, its pH dependence, and how this affects B6 absorption. How does the coenzyme work biochemically?
• article should state explicitly somewhere that there are 6 vitamers of B6
  • Done. David notMD (talk) 11:20, 22 August 2021 (UTC)
• article does not mention yeast extract nor wheat bran as particularly high dietary sources
  • Table not meant to be comprehensive, so supplement-type 'foods' not included. David notMD (talk) 11:20, 22 August 2021 (UTC)
• no mention that much of plant-based B6 is in the form of a bound glucoside conjugate 5-O-(β-D-glucopyranosyl)pyridoxine; this is relevant because this plant-based form has a lower bioavailability.
• no mention of the fact that bacterially synthesized B6 in the large intestine is a potential exogenous source
  • Text and ref added into Sources to address endogenous bacteria contribution of B6. David notMD (talk) 18:01, 20 August 2021 (UTC)
• no mention of the vitamin B6 salvage pathway? PMID 30037155
  • Parra 2018 ref and salvage incorporated into Absorption, salvage and excretion. David notMD (talk) 03:24, 22 August 2021 (UTC)
• what happens to newly absorbed B6? There’s no mention of the fact that it gets delivered to the liver to get converted to the active form for circulation.
  • Incorporated into Absorption, salvage and excretion. David notMD (talk) 03:24, 22 August 2021 (UTC)
• no mention of how newly formed PLP, contained in small, rapid turnover pools – independent of the endogenous coenzyme pools – get released into the bloodstream attached to albumin
  • Incorporated into Absorption, salvage and excretion. David notMD (talk) 03:24, 22 August 2021 (UTC)
• what enzyme is responsible for the conversion to 4-pyridoxic acid?
  • Incorporated into Absorption, salvage and excretion. David notMD (talk) 03:24, 22 August 2021 (UTC)
• what is the typical total body pool of B6? Where is most of it located?
  • Incorporated into Absorption, salvage and excretion. David notMD (talk) 03:24, 22 August 2021 (UTC)
• ”alcoholics have an increased risk of vitamin B6 deficiency” there’s so much more that could be said about this. I think at the bare minimum this article should summarize how alcohol intake affects B6 metabolism.
  • Removed mention of alcohol intake as lowering plasma PLP, as evidence limited to two very old clinical trials (PMID 7174224 and 4359937) David notMD (talk) 18:01, 20 August 2021 (UTC)
• it is assumed that the reader will know abbreviations such as mmol, nmol/l, mg, but these units should be written in full on first use, and/or linked.
• the significance of B6 is the biosynthesis of chlorophyll is only briefly mentioned in the “Definition” section; surely this should be elaborated a bit a placed in the “Functions” section?
  • Created a referenced "In plants" subsection in Functions, but removed mention of chlorophyll synthesis, as not supported by ref that was in article or any other literature. David notMD (talk) 10:45, 15 August 2021 (UTC)
    • Subsequently found confirmation of B6 requirement for chlorophyll synthesis, also plant hormones, so added that, with Parra as ref for both. David notMD (talk) 14:48, 25 August 2021 (UTC)
• should mention importance of B6 in nucleic acid biosynthesis
• the coenzymatic role of B6 in glycogenolysis is mechanistically different than in amino acid metabolism, and is probably worth a mention
  • Better explanation.
• no mention of how B6 is important in the regulation of steroid hormone action
  • Could not find useful sci literature on this topic. David notMD (talk) 20:05, 24 August 2021 (UTC)
• is vitamin B6 deficiency associated with defects in immune function?
  • A lit search found no useful review literature for B6 and defects in immune function (or inflammation). One meta-analysis described and referenced for cardiovascular/coronary disease added to the Research section. David notMD (talk) 15:30, 13 August 2021 (UTC)
• no mention that because of its chemical stability, pyridoxine hydrochloride is the primary chemical form used in food fortification and multivitamin supplements
• what is the role of vitamin B6 in diabetes? PMID 32456137
  • Suggested ref not used. Too much of the evidence in this review was non-human. Evidence divided between diabetes causing low B6 and low B6 causing diabetes. No other literature provided review of multiple clinical trials for higher B6 intake preventing or treating diabetes. David notMD (talk) 10:42, 13 August 2021 (UTC)
• have B6 deficiencies been linked to depression? PMID 27655070 PMID 33251075
  • Suggested refs not used, as not specific for B6. Two review refs found and incorporated into the Research section. David notMD (talk) 10:42, 13 August 2021 (UTC)
• there is an updated (2020) “D-A-CH reference values for nutrient intake” that might be useful as an additional, more recent source for dietary than two currently used in the article
• from what source is the B6 used in dietary supplements obtained?
  • Commercial synthesis subsection added with referenced content describing current process for chemical synthesis, also exploration of fermentation biosynthesis. David notMD (talk) 21:35, 16 August 2021 (UTC)
• any relationship between B6 and epilepsy? PMID 31340680 Multiple sclerosis? PMID 28875857 Cancer? PMID 28376200 PMID 30271425 PMID 29477221 PMID 31262866 PMID 32208818 Does B6 supplementation help old people with cognition? PMID 28248558
  • PMID 31340680 and 28376200 incorporated into article in Genetic defects subsection and Research section, respectively. The other refs listed were not WP:MEDRS. Other refs found about B6 and cognition (not conclusive). David notMD (talk) 21:03, 12 August 2021 (UTC)

Based on this, and the existing citations needed tags, I think the article is still quite a ways from meeting the good article criteria at this time. For that reason, I will close this submission as not promoted at this time, and hope the nominator resubmits in the future. Esculenta (talk) 22:53, 11 August 2021 (UTC)

A good overview provides doi:10.3390/cells7070084, e. g. enzyme names + biochemistry. --Julius Senegal (talk) 07:16, 13 August 2021 (UTC)

Thanks. Parra 2018 now used several times as a ref. David notMD (talk) 14:50, 25 August 2021 (UTC)

Added Medical uses and Research sections, and Fortification and Commercial synthesis subsections. David notMD (talk) 16:21, 13 August 2021 (UTC)

Serving

What does "per serving" mean? Usually, you indicate the amount per 100 mg or 1000 mg. --Julius Senegal (talk) 07:21, 13 August 2021 (UTC)

Valid point. From looking at all vitamin articles, B1, B2, B12 and Pantothenic acid have no table, K and B6 have per serving, and Folate, Niacin, Biotin, A, C and E have per 100 grams (D has per gram). I will change the B6 table to per 100 grams. David notMD (talk) 10:59, 13 August 2021 (UTC)

Change to amounts of B6 per 100 grams. David notMD (talk) 20:13, 18 August 2021 (UTC)

August 2021

Bullet points of the GA rejection are being addressed. As of August 25, number of references has increased from 28 to 58, and article bytes from 28,000 to 50,900. The intention is to address all bullet points in the review, then resubmit a GA nomination. Participation by all editors is welcome. David notMD (talk) 10:52, 24 August 2021 (UTC)

Resubmitted to GA nomination. David notMD (talk) 20:29, 25 August 2021 (UTC)

I may not have internet access Sept 17-26, so please do not start the GA review during that time. David notMD (talk) 03:33, 14 September 2021 (UTC)

Chembox or Drugbox or Infobox Drug?

Which format is preferred? What are the sources of information to remedy this? Some of the vitamins have the compact Drugbox, while others have a longer Infobox Drug or Chembox. David notMD (talk) 08:32, 26 August 2021 (UTC)

GA Review

This review is transcluded from Talk:Vitamin B6/GA2. The edit link for this section can be used to add comments to the review.

Reviewer: Psiĥedelisto (talk · contribs) 21:01, 23 September 2021 (UTC)

GA review – see WP:WIAGA for criteria

---

 Passed—This well written article was exhaustively corrected by David notMD in the previous GA review, above, point by point. David notMD decided to request that users not GA review this article until the 26^th; I found such request impractical for two reasons: ① I planned to pass the article after reading it; ② it's deep in the GAN backlog. Therefore, I accepted it today, the 23^rd. Some problems with the article remain, but as even featured articles may have problems, much less good articles, that's no reason for an overall fail. Psiĥedelisto (talk • contribs) ^{please always ping!} 22:41, 23 September 2021 (UTC)

1. Is it well written?

   A. The prose is clear and concise, and the spelling and grammar are correct:

   I noted that we were quoting an official English translation of the Ministry of Health, Labour, and Welfare of Japan which was Engrish-lite. I switched this out for a proper translation and properly cited the original Japanese terms and quotes being referred to, thus resolving the issue I found.

   B. It complies with the manual of style guidelines for lead sections, layout, words to watch, fiction, and list incorporation:

2. Is it verifiable with no original research?

   A. It contains a list of all references (sources of information), presented in accordance with the layout style guideline:

   B. All in-line citations are from reliable sources, including those for direct quotations, statistics, published opinion, counter-intuitive or controversial statements that are challenged or likely to be challenged, and contentious material relating to living persons—science-based articles should follow the scientific citation guidelines:

   C. It contains no original research:

   D. It contains no copyright violations nor plagiarism:

3. Is it broad in its coverage?

   A. It addresses the main aspects of the topic:

   B. It stays focused on the topic without going into unnecessary detail (see summary style):

4. Is it neutral?

   It represents viewpoints fairly and without editorial bias, giving due weight to each:

5. Is it stable?

   It does not change significantly from day to day because of an ongoing edit war or content dispute:

6. Is it illustrated, if possible, by images?

   A. Images are tagged with their copyright status, and valid fair use rationales are provided for non-free content:

   B. Images are relevant to the topic, and have suitable captions:

   I am failing the article on this criteria despite giving it an overall pass because I don't believe that the current images are enough to pass exactly the "relevant" criterion. B₆ injections are commonly given in hospitals (usually labeled pyridoxine HCL), and B6 supplements are often seen. I believe that images of these should be included somewhere, as well as the freebase form if possible. Seems to just be a white powder, but still.

7. Overall:

   Pass or Fail:

Wake/Sleep Promoting?

Is there any evidence to support either, or both? B6 is part of many wake(energy) products, but I've also seen it(as sole B vitamin) in my sleep promoting product.

I don't see anything to suggest it plays a major role in either on this page. Unless certain reactions can only happen when the body is in an awake/asleep state.

But it is not made clear if that is the case.

Since it is part of practically all energy drinks and energy promoting b-complex vitamins, should there not be a section to address that? 2003:C7:872D:DB90:DD9:1EFA:E7B4:9CD5 (talk) 23:45, 21 September 2022 (UTC)

The short answer is no and no. As a person who provided science consulting services to U.S. dietary supplement companies, I learned that often a multi-ingredient product may have one ingredient for which there is some eviedence. This is the 'tent-pole' ingredient that justifies the Structure:Function health claim. For a sleep product, that ingredient is often melatonin, with the other perhaps 'window dresing' Examples include Chamomile, Magnesium,Passion Flower, Tryptophan, Valerian, Vitamin B6.

There is a claim that vitamin B6 has an impact on sleep. One theory is that the vitamin is necessary to convert tryptophan to serotonin, which is the precursor for melatonin, a sleep-inducing hormone. The scientific evidence is scant. In the one published human trial (Luboshitzky 2002) healthy men consumed 100 mg pyridoxine or placebo at 5:00 PM. Serum melatonin and core body temperature measures were taken every 30 minutes until 3:00 AM. Peak melatonin was 47.2 pg/ml for treated and 53.9 for placebo (not significant). Evening/night decline in body temperature did not differ between groups, nor sleep amount, nor sleep quality. A no-author rat study published (2007) in an obscure Russian journal reported that rats injected with pyridoxine for two months had a 36% increase in evening melatonin.

All B vitamins are necessary to convert body sugar, glycogen, fat and protein to energy. This matters for people who are deficient, but the evidence is scant that taking larger than the RDAs has any benefit for mobilizing energy. David notMD (talk) 01:22, 22 September 2022 (UTC)

Half-Life

I see that a question from 2006 is still not addressed regarding half-life of vitamin B6: [1]

The source https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/#en8 tells "Although the body absorbs large pharmacological doses of vitamin B6 well, it quickly eliminates most of the vitamin in the urine", citing PMID 20373888.

It seems that pyridoxal-5’-phosphate (PLP), (once release to circulation from the organs such as liver) is quickly degraded, with 4-pyridoxic acid (PDA) as a major inactive metabolite, but I didn't find this rate of degradation. Is there any data published?

Also, it seems that pyridoxine hydrochloride, a pharmaceutical vitamin B6, is not always converted to PLP, as described in PMID 838399. Are there more data on that?

What is the rate of conversion from pyridoxine hydrochloride to PLP? Is this data known?

What is the effective biological half-life of the active forom of vitamin B6 after vitamin B6 ingestion as pyridoxine hydrochloride? From doi:10.1007/978-3-319-20790-2_174-1 I understand that this value is up to 20 days. Is my understanding correct?

The page [[2]] gave half-life duration of 25–33 days, citing this source: Assessment of vitamin B₆ intake in relation to tolerable upper intake levels. Opinion of the Panel on Nutrition, Dietetic Products, Novel Food and Allergy of the Norwegian Scientific Committee for Food Safety (PDF). Oslo, Norway. ISBN 978-82-8259-260-4. Archived from the original (PDF) on 2019-11-17. Retrieved 2019-12-07. Eighty to ninety percent of vitamin B6 in the body is found in muscles and estimated body stores in adults amount to about 170 mg with a half-life of 25-33 days.

Since once source give value of 25-33 days while another source give value of up to 20 days, will it be correct to cite both sources and mention that the half-life value is "around 20 days"? Will be correct if I modify buth the pages for both Pyridoxine and Vitamin B6 (but not for PLP) and specify the value of "around 20 days" as a biological half-life for each?

Another option would be to mention both sources: "The half-life of vitamin B6 varies according to different sources. One source suggests it can be up to 20 days[source1], while another source indicates a range of 25 to 33 days[source2]."

And to make a concluding statement: "After considering the different sources, it can be concluded that the half-life of vitamin B6 is typically measured in several weeks.[source1][source2]"

Maxim Masiutin (talk) 23:07, 20 March 2024 (UTC)

@David notMD, can you please peer-review my edits in articles related to vitamin B6 half-lilfe, and let us know that my edits were OK? As an alternative, we can put tags such as so that we would not forget to check that later? These articles on vitamins are very important as they seem to have high impact, so have to double-check everything here. Specifically, I refer to the following statements that I added or modified:

• Megavitamin-B6 syndrome: While vitamin B6 is water-soluble, it accumulates in the body. The half-life vitamin B6 is measured at around two to four weeks, it is stored in muscle, plasma, the liver, red blood cells and bound to proteins in tissues.
• Vitamin B6: The half-life of vitamin B6 varies according to different sources: one source suggests that the half-life of pyridoxine is up to 20 days, while another source indicates half-life of vitamin B6 is in range of 25 to 33 days. After considering the different sources, it can be concluded that the half-life of vitamin B6 is typically measured in several weeks.
• Pyridoxine: The half-life of pyridoxine varies according to different sources: one source suggests that the half-life of pyridoxine is up to 20 days, while another source indicates half-life of vitamin B6 is in range of 25 to 33 days. After considering the different sources, it can be concluded that the half-life of pyridoxine is typically measured in several weeks.

Maxim Masiutin (talk) 02:33, 19 April 2024 (UTC)

I am still uncomfortable with using the term "half-life" for vitamins. From Half-life "A biological half-life or elimination half-life is the time it takes for a substance (drug, radioactive nuclide, or other) to lose one-half of its pharmacologic, physiologic, or radiological activity. In a medical context, the half-life may also describe the time that it takes for the concentration of a substance in blood plasma to reach one-half of its steady-state value (the "plasma half-life"). The relationship between the biological and plasma half-lives of a substance can be complex, due to factors including accumulation in tissues, active metabolites, and receptor interactions." (my bold). How fast a healthy person becomes deficient and how fast a deficient person is restored to normal range with supplementation may be more relevant. I will still look for literature that uses the phrase "half-life", but am not promising I will find enough to warrant incorporating that into articles. David notMD (talk) 19:49, 19 April 2024 (UTC)

Your observation is justified. The term "biological half-life" does not easily apply to vitamins, because the body does not try to fully eliminate a vitamin same way as it eleminates a xenobiotic such as modafinil. Vitamins are not xenobiotics. It is also hard to use the term "plasma half life" (elimination half life) because body does not try to fully eliminate a vitamine. Yet, the body eliminates excessive vitamine. emphasizing that this term is only relevant when the vitamins are taken as pharmacologic substances, such as niacin 1000 mg taken as a medication rather than 10-20 mg consumed with food. This is an example on why the notion of biological half-life does not apply for vitamins. However, when vitamins are taken a a pharmacologic substance, we can tell of "overdose", "toxicity" and we can there mention the plasma half-life.

For example, consider the following quote from the article on CYP4F2 enzyme: CYP4F2 plays a pivotal role in modulating circulating levels of vitamin K1 by ω-hydroxylating and deactivating it. In the liver, where this enzyme is predominantly expressed, it functions as a primary oxidase responsible for metabolizing vitamin K1 into hydroxylated forms. By doing so, it acts synergistically with VKORC1 to prevent excessive accumulation of biologically active vitamin K in. Termed the "siphoning" pathway, this mechanism primarily occurs when there is an excess amount of vitamin K1 present. This enzymatic process positions CYP4F2 as a critical negative regulator for maintaining appropriate levels of active vitamin K1 within the body. In this context, the article on Vitamin K can contain information on half-life of the excessive share that the body tries to eliminate. Maxim Masiutin (talk) 21:21, 19 April 2024 (UTC)

ULs

The article now highlights the fact that the United States set ULs in 1998 based on available science at that time, but since then, other country's regulatory agencies have set lower ULs, the most recent being the EFSA, which had set adult UL at 25 mg/day in 2008 and then revised to 12 mg/day in 2023. David notMD (talk) 11:39, 19 July 2024 (UTC)

Water soluble sentence is garbled and misplaced.

The sentence "Vitamin B6 is a water-soluble vitamin, one of the B vitamins" in the Definition section looks like a poor copy/paste result.

1. "one of the B vitamins" really shouldn't be there.

2. The information about it being water soluble doesn't seem to belong in that part of the paragraph.

3. Citation needed for solubility.

 JPGoldberg (talk) 12:55, 18 October 2024 (UTC)