Talk:Biotin/Archive 1

Archive 1

spam?

I'm not sure if this is a dead link or just spam, can anyone figure it out? The title of the supposed article looks fishy to me, like synthetic text. Anyway, right now the link just goes to an advertisement page. Helikophis (talk) 04:11, 16 January 2013 (UTC)

Without heading

These comments were formerly at the top of the talk page, without heading. Icek 11:25, 4 August 2007 (UTC)

Where does Biotin occur naturally, if anywhere? The article doesn't make it clear Coyote-37 14:23, 5 October 2005 (UTC)

I agree, and furthermore I think this article as a whole is too technical. Joe average seeking information on Biotin will be befuddled.

The Italian article mentions milk (human and bovine), egg yolk and seafood, and says that in vegetables the bioavailability is low. I don't agree that the article is too technical. Icek 16:23, 30 April 2007 (UTC)

By today, Jan 29 2017 it has still not be mentioned where biotin occurs, or is being produced, naturally.

Note to the moderators: This last paragraph required editing. It was written in ignorance and was offensive to those of us who not only use alternative therapies and its components, such as apricot kernels, but also deal with a great many people who have indeed cured themselves of cancer and various other diseases as a result of their use. It would seem the writer of this overview chooses not to thoroughly research the subjects of his drivel before imposing them upon unsuspecting knowledge seekers. Highly irresponsible. This person should have his privileges revoked and all writings should be thoroughly reviewed for similar content. Please remove this message once read. Many thanks.

This is good!!

Copyright violation?

Some of this article seems to have been "adopted" from http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/bio_0035.shtml and I don't have the time to find the copyright template. MeekMark 02:32, 1 August 2006 (UTC)

It seems it has been removed/rewritten in the meantime, so there should be no copyright problem now. Icek 11:23, 4 August 2007 (UTC)

Poor Wording

"Biotin deficiency is a rare nutritional disorder caused by a deficiency of biotin" What is this sentence trying to say? Maybe this can be rewritten if the author's original meaning is known. nChanq 21:52, 22 August 2006 (UTC)

"Vitamin H may also refer to haloperidol"- this is confusing, inaccurate and may be removed. If needed, origin of "H" in vitamin H may please be mentioned. We need more modern information and state clearly that it is an enzyme cofactor.Ck.mitra 07:39, 30 August 2007 (UTC)

What is biotin supplement made of?

I have been unable to find info on the manufacture of biotin for human supplementation. In lay terms, how is biotin produced, from what materials? Thanks. 74.38.116.21 19:28, 12 November 2006 (UTC)V.B.

I have the same question as the guy above, and also, can biotin be synthetically manufactured for use in vitamins, supplements, etc.? I also agree with nChang, that sentence makes no sense. 141.156.142.13 22:11, 26 November 2006 (UTC) AnimeKing99

While I don't know how it is manufactured commercially, it certainly can be manufactured. One path starts with cysteine, which is also used by organisms as a building block for biotin. See here for (unfortuately only the first page of) an article about that synthesis. And you could try searching for biotin "total synthesis" in Google Scholar (which returns only scholarly articles, but often without free fulltext access) or in a normal search engine. Icek 16:15, 30 April 2007 (UTC)

Links for Biotin Info

Here's two great websites that have lots of info on biotin that may not be mentioned here: [1] and [2], the first link is for really smart people, it's really complicated, but the second link is a lot easier to understand, and lists a lot of the places where biotin occurs naturally. Hope that helps!! ;) 141.156.142.13 22:24, 26 November 2006 (UTC) AnimeKing99

Excessive consumption of raw egg-whites

deficiency can be caused by excessive consumption of raw egg-whites over a long period (months to years)

What constitutes "excessive consumption"? 2 eggs per day? 5? Icek 17:04, 5 April 2007 (UTC)

I believe that two raw egg whites per day can, in fact, be considered excessive consumption for many people. In general, the more raw egg whites you eat, the faster the symptoms appear. A dozen raw egg whites (which provides about 200 Calories or 50 g protein) each day might produce symptoms in as little as two weeks. Most docs prefer that their patients avoid eating raw egg whites entirely. WhatamIdoing (talk) 00:00, 17 December 2007 (UTC)

Hmm... to bind 0.3 mg biotin you should need the avidin from 11 eggs (see my comment at Talk:Avidin#Digestability). 2 egg whites should bind about 0.05 to 0.06 mg - is this already harmful? Most docs probably prefer a wide safety margin. Icek (talk) 17:22, 29 December 2007 (UTC)

Excess symptoms

The symptoms described for excess of biotin are not documented anywhere. Alopecia is a sign of biotin deficiency, not excess. At least google it.

See the Dietary Reference Intake section - about no setting of a safe upper limit because no clear evidence for adverse effects from high doses.David notMD (talk) 04:28, 5 March 2016 (UTC)

RDA

RDA, ADI or the like. Since it is produced by intestinal bacteria surely those on antibiotics may require supplementation? --41.241.192.53 (talk) 10:31, 20 November 2007 (UTC)

Only vitamin K deficiency turns up in the science literature as a vitamin deficiency caused by antibiotics killing intestinal bacteria in the large intestine. As assumption could be made that for other vitamins synthesized and secreted by bacteria in the large intestine, the contribution is minor compared to what is consumed in food and absorbed in the small intestine.David notMD (talk) 11:41, 21 May 2016 (UTC)

Biotin

Thank You so much for having this website. I had a project for scholl and this helped me so much. THANKS;] —Preceding unsigned comment added by 67.167.28.250 (talk) 17:45, 30 March 2008 (UTC)

I have used Biotin for my hair, I don't really have a hairloss problem. I only use it because I heard it makes your hair grow longer. Wel my hair and nails grow faster and I have alot of new hair so it definately works!

Binding coefficient references

The article contains the three "references" (Bonjour, 1977; Green 1975; and Roth, 1985) for the binding constant of biotin to streptavidin and avidin. The first two incomplete references appear to refer to

• Bonjour JP. (1977). "Biotin in man's nutrition and therapy -- a review". Int J Vitam Nutr Res. 47 (2): 107–18. PMID 142069.

• Green NM. (1975). "Avidin". Adv Protein Chem. 29: 85–133. PMID 237414.

and this paper might be helpful. (but I don't have subscriptions to any of them)

• Bayer EA, Ben-Hur H, Wilchek M. (1986). "A sensitive enzyme assay for biotin, avidin, and streptavidin". Anal Biochem. 154 (1): 367–70. doi:10.1016/0003-2697(86)90538-5. PMID 3706735.{{cite journal}}: CS1 maint: multiple names: authors list (link)

Whosasking (talk) 13:35, 19 July 2008 (UTC)

redundant

LKS (fatty liver and kidney syndrome) and hepatic steatosis also can occur.

hepatic steatosis = fatty liver the sentence is redundant. —Preceding unsigned comment added by AriaNo11 (talk • contribs) 21:34, 26 September 2008 (UTC)

Controversial addition

I removed the following from the article. It included no sources and an anonymous user has been simply rewording the paragraph (possible COI/POV):

Besides its roles as a carboxylase prosthetic group, biotin also has effect on DNA, gene impression as well as cell development and immunity. Strong correlation between biotin status and gene expression is founded by different research groups. The major attention is focused on biotinylation of histone. Histones are protein that binds to DNA. It plays important role in packaging DNA to its compact structure to form nucleosome which is considered as an integral structural components of chromosomes. Releasing of this compact is tightly associated with DNA replication and transcription. Modification of histones through the attachment has been shown to affect replication and transcription of DNA.

--Odie5533 (talk) 03:47, 16 March 2009 (UTC)

Verifiability of part of the deficiency section + cleanup

I have now removed the blank reference tags from this section, so that unverified information in this article does not falsely appear to be verified. In addition, the last part of the section needs a serious cleanup by someone who both knows English well, and is able to find a source for the claims in question. (It looks to me to be poorly translated from a possibly dubious source in a different language.) Any ideas for improvement? Mirithing (talk) 22:54, 19 March 2009 (UTC)

Metabolism

The article indicates that "Biotin is necessary for cell growth, the production of fatty acids, and the metabolism of fats and amino acids". However, metabolism is a term that can mean either anabolism or catabolism. Is biotin necessary for both? This may be worth clarifying. —Preceding unsigned comment added by 169.232.116.47 (talk) 03:38, 14 October 2009 (UTC)

Sources

"The best natural sources of biotin in human nutrition are [...]. These sources of biotin include [...]." seems a bit redundant and confusing. Also, eggs are listed, but later it's noted that raw egg whites can cause deficiency. Is it cooked eggs, or egg yolks only (raw/cooked?), that are a good source of biotin? Chi11ken (talk) 00:07, 21 October 2009 (UTC)

Under Bioavailability the following seems to conflict with the explanation in the introduction which states that humans get all their biotin from bacteria that dwell in the gut......Please clarify. Also, the logic below is rather nonsensical...sounds like confusion over the definition of "bioavailability". "A possible explanation for the wide variability in biotin bioavailability is that it is due to ability of an organism to break various biotin-protein bonds from food. Whether an organism has an enzyme with the ability to break that bond will determine the bioavailability of biotin from the foodstuff.[12] —Preceding unsigned comment added by 206.77.150.101 (talk) 21:45, 7 December 2010 (UTC)

Yes, raw eggs contain avidin an antinutrient which binds to biotin in the body. Cooking at over 185F degrees and holding that temperature throughout for at least 4 minutes significantly deactivates these substances.66.110.251.145 (talk) 04:03, 15 June 2012 (UTC)

No Sources

However, a number of metabolic disorders in which an individual's metabolism of biotin is abnormal exist; in these disorders, megadoses of biotin, far higher than the average daily intake from food, in general, can mitigate symptoms and correct the underlying metabolic disturbance.

Statement has no sources. 70.61.199.67 (talk) 17:25, 27 May 2011 (UTC)

I removed the part about megadoses, and requested citation for the bit about metabolic disorders. ChemNerd (talk) 17:52, 27 May 2011 (UTC)

This is only common sense and you need no "sources" to know that if the normal amount doesn't work because of a biotinadase deficiency, then more might help. I guess if I find sources for what even the most stupid person already knows on this, I will post them here. We don't need establishment group think here to state the obvious. Now, I am losing hair, maybe I can take about 5-7 "high potency" tabs a day and see what happens, not that the policies here will let me use that ("original research" - convenient cop-out for removing what personally offends). Oh, and if this is not true, then why do we list treatment doses for hair and nails that are 10-30 times the strongest OTC tablets? Why not take the RDA level? So why contradict ourselves? I reverted that once to more reasonable doses and someone changed it back. Oh, and if I find the correct values as sourced by several good sources, I will post it here, though it seems everyone here cannot think for themselves without sources. 66.110.251.145 (talk) 03:57, 15 June 2012 (UTC)

Allergy Information

Could someone please add allergy information? I bought biotin supplements and only took them twice then stopped. Each day I took them, within a couple hours I started feeling horrible, dizzy, nauseous, short of breath. I realized the only thing I did differently on those days was take biotin, so I came here looking for allergy info, and found none. — Preceding unsigned comment added by 151.112.62.23 (talk) 19:35, 10 August 2011 (UTC)

Possible dosage misinformation

It seems both the therapeutic and the supplemental dosages are off by 10. I read the source given and I do not trust it as reliable. On the website, it says the RDA is 30 mcg, but I have a bottle in front of me that has 1000 mcg and is clearly labeled as 3-1/3 times the RDA. So convert that to 10/3 the RDA and divide 1000 by 10 and then multiply by 3, you get 300 mcg. 100% is 300 mcg and 333% is 1000 mcg (1 mg). Now, you say that the supplemental dosage and the therapeutic dosage is different by a magnitude, but what your source lists is 2 orders of magnitude. It seems they are an unreliable source and should be removed. I guess I should look for other sources and see what the consensus is between them. I believe the dosages listed here are very inaccurate and possibly dangerous (more on the bottom end than the high end, albeit). If I find other numbers on multiple sites I find credible, I will post them here. 66.110.251.145 (talk) 03:41, 15 June 2012 (UTC)

Adequate Intake (AI; there is no RDA) is correct at 30 mcg. Last revised in 1998. In the U.S., product labels use % Daily Value. These DVs have not been updated since 1968, so represent an outdated concept of how much is needed. The 100% DV for biotin is 300 mcg. A product contain 1000 mcg will be 333% DV, but 3333% of what is considered adequate to meet adult needs. Other vitamins and minerals do not align between RDA and 100% DV, but none are so far apart as biotin.David notMD (talk) 23:41, 4 March 2016 (UTC)

Daily Values for many nutrients, including biotin have been revised. Adequate Intake for biotin currently set at 30 micrograms. 100% Daily Value, ditto. This resolved the old disconnect in which AI had been revised downward to 30 mcg but DV had still been at 300 mcg. David notMD (talk) 10:44, 15 July 2017 (UTC)

Biotin virtually never at 100% in multi-vite supplements

This probably can't be worked into the article, but I've always found it odd that "balanced" or "complete" multivitamin supplements never contain 100% the RDA for biotin, usually only about 15%. I wonder why. — Preceding unsigned comment added by 199.242.72.225 (talk) 20:49, 19 November 2012 (UTC)

What labels show is a % Daily Value. The problem is that DVs were based on old (1968) calculations that the biotin requirement was 300 mcg/day. The 1998 update cut this by 90%, meaning that an Adequate Intake (sufficient for all adults) is only 30 mcg. So as you reported, biotin in multi-vit/min is very often at 30 mcg and hence "only" 10% DV, whereas in reality is providing 100% of the AL. In May 2016 the Daily Value was change to 30 mcg. Food and supplement companies have until July 2018 to comply. Until then, there will be products in stores using the old or new DVs.David notMD (talk) 11:35, 21 May 2016 (UTC)

US label compliance later delayed to 2020. David notMD (talk) 16:51, 28 December 2020 (UTC)

History of century old British breakfast of raw or semi cooked eggs

Somewhere I have got a reference that there is a history about a century back in the British isles that their breakfast used to consist of raw or semi cooked eggs which on being taken regularly would subsequently lead to the people passing out (of hypoglycemia) at around 11am at work. I am searching for the validity of the statement. Meanwhile, this article may be of some relevance. Requesting insights if anybody knows anything about this. Diptanshu^Talk 15:50, 17 June 2013 (UTC)

Dietary Reference Intake

I am creating the same format for DRIs for all 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) if there is enough information to set a UL. 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, then rationale is covered in a Toxicity section. In addition to DRIs, the U.S. also established Daily Values, using these on food and dietary supplement labels as % DV. DVs were based on 1968 RDAs, but as of May 2016 have been updated to reflect the newer DRIs. 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) 11:31, 21 May 2016 (UTC)

Updated December 2020 to reflect implementation of newer Daily Values on labels. David notMD (talk) 16:37, 6 January 2021 (UTC)

Best sources

Up until deletion, this article contained many good sources of biotin. I propose that we list an adequate number of good food sources, along with a few mediocre, but possibly more common ones as well. I understand that we can't have a list with thousands of entries in such an article, but it would make more sense to gather the examples based on the above criteria. As I now see it, the current examples are more of a random subset instead of serving as useful guidance. bkil (talk) 15:33, 31 December 2018 (UTC)

On my talk page, you said: "Could you please explain why you have removed a majority of sources in the article? If you think the list is too long, we could collapse it, or perhaps remove some of the items from the end, but definitely not the best available sources. https://en.wikipedia.org/w/index.php?title=Biotin&action=historysubmit&type=revision&diff=871504992&oldid=814424179 I would like to see at least the best sources restored." I don't see what edit of mine disrupted any sources. Could you recheck and be more specific please? Respond here. --Zefr (talk) 17:21, 31 December 2018 (UTC)

Somewhere near the middle of this mega-diff, the reference to the Japan official data (grep mext.go.jp) was removed and those source examples were removed that came from there. Also if we wanted to stick to a single source here, the original publication that the current section references lists quite a few more: [3]. Although, if you think that combining data from separate sources in a single table can be misleading (more recent, but with different methods & supplies), we could split such overview to separate tables. Again my aim here is not to list all publications or all food stuff, rather to highlight some of the most biotin-rich, but still accessible foods. I was startled that lots of good sources that I use daily were missing. It is unfortunate that the individual articles of foodstuff are missing biotin content because the infoboxes are imported from the FDA, and their tables lack this information as of now. bkil (talk) 18:01, 31 December 2018 (UTC)

Shouldn't we provide encyclopedic content and a synthetic source, such as this? Let's focus on keeping it simple for the typical, unscientific user. --Zefr (talk) 18:24, 31 December 2018 (UTC)

I have opened the given link earlier. If you click reference number 47 right above the table, open pubmed, and on the right hand panel click "Free full text", it will open the link I have provided above. This is the source publication behind the original reference. Please investigate. There you can find full tables from which the given "layman's table" was extracted with much more data. Copy&pasting a table directly doesn't make Wikipedia any more encyclopedic. You need to use common sense judgement to know what to present to readers. Maybe there's a language barrier between us, so could you please clarify a bit more what you seem to disagree with? Are you trying to imply that the panel of the Ministry of Education, Culture, Sports, Science and Technology, Japan is doing "unscientific" work? Anyway, why are we preferring the Utah source from 2003 if there is an authentic one available from 2015? bkil (talk) 18:55, 31 December 2018 (UTC)

Stepping back to see the big picture: coming to the Wikipedia article of Biotin, the common reader would rightly expect to see a list of major dietary sources available. Do you imply that simple minded people have no right to informed dietary decisions? The original version was missing many great sources of Biotin, thus I extended the list, until they were removed. Let me rephrase that I would *not* like to list all kinds of foodstuff here, as I agree that items having low biotin content are more of scientific interest. bkil (talk) 18:55, 31 December 2018 (UTC)

Also, after checking some of your numbers, I do not agree with the current presentation of some of the ranges. For example, even the source summary table contained 0.02-6 for whole-wheat bread, that we have decided to present as "up to 6". This is misleading, as this particular study measured just 0.02, so bread from the upper range may be some kind of specialized bread having extra ingredients, but definitely not common bread (bread showed the largest relative difference here, but some of the other items also showed great variety). bkil (talk) 18:55, 31 December 2018 (UTC)

P.S.: if you do find a fresh source that includes a list of all major biotin sources, we can reference that instead and include a table derived from there - that would be fine with me. What matters to me as said above, that the reader gets what she is rightly looking for. bkil (talk) 19:00, 31 December 2018 (UTC)

The ODS-NIH (dated 9/18) and Linus Pauling (dated 10/15) sites provide current information and are the best summary sources available. I agree the whole wheat bread maximum of up to 6 μg per slice seems odd and unsupported, so could be changed or perhaps better just removed. As the source information doesn't change much over time, we should provide general references that fulfill the need, and discuss them simply. This isn't complicated and doesn't need so much discussion to settle on what's best for the general reader. --Zefr (talk) 19:31, 31 December 2018 (UTC)

The chart in the ODS-NIH reference labeled "Table 2: Selected Food Sources of Biotin [5]" refers to the very same article from 2004 that I have linked above at least twice. I have no problem with that article, but let me reiterate that even this piece of limited research contains much better data than the summary at ODS-NIH. The table in the LPI references another paper along with the 2004 one, asserted as "Briggs DR, Wahlqvist ML. Food facts: the complete no-fads-plain-facts guide to healthy eating. Victoria, Australia: Penguin Books; 1988.". I haven't checked this one. I decided to open this thread after noticing the change as I've seen you are a professional in the field and wanted to make sure that I am not missing anything obvious. So now I'll adjust the table to show more good dietary sources than bad sources based on the original 2004 paper already referenced transitively. Eventually as I have some more time, I'll try to find a more up to date, notable research paper that carries a summary table so we can copy that in the long run. bkil (talk) 13:46, 6 January 2019 (UTC)

Considering GA nomination

Checking all references prior to considering GA nomination. David notMD (talk) 16:52, 28 December 2020 (UTC)

Added Research section. David notMD (talk) 15:12, 5 January 2021 (UTC)

Added to section on high dose biotin interference with labs tests. David notMD (talk) 16:35, 6 January 2021 (UTC)

I'm not really sure what the graph in the Bioavailabilty section is supposed to be saying to the reader. CV9933 (talk) 17:00, 6 January 2021 (UTC)

Dose pharmacokinetics, I suppose, but nothing in the text covers that, and the figure itself is not referenced. As there is no known health benefit from raising plasma concentration of biotin, not sure there is any value to keeping the figure. David notMD (talk) 19:33, 6 January 2021 (UTC)

Exactly and for those reasons I would agree with removing it. CV9933 (talk) 20:51, 6 January 2021 (UTC)

I will move it to my Sandbox while trying to decide if of any value. The image content at Commons had a journal ref, so will look at that. David notMD (talk) 21:35, 6 January 2021 (UTC)

Nominated. Will continue to work on improving while awaiting a reviewer. David notMD (talk) 01:07, 9 January 2021 (UTC)

Replaced Sources table (replacement modeled on tables in other vitamin GA articles) and added to History. David notMD (talk) 17:21, 11 January 2021 (UTC)

GA Review

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

Reviewer: HaEr48 (talk · contribs) 21:51, 16 January 2021 (UTC)

Will look at this. Looking forward to review it while educating myself in another vitamin, David notMD! HaEr48 (talk) 21:51, 16 January 2021 (UTC)

Initial comments:

• Biotin is composed of a ureido ring … any link for ureido?
  • No link for ureido ring. I added chem compostion. David notMD (talk) 04:01, 18 January 2021 (UTC)
    • –N–CO–N– is not a ring, so maybe we should say a ring containing the –N–CO–N– group? HaEr48 (talk) 23:12, 30 January 2021 (UTC)
      • Done David notMD (talk) 21:12, 31 January 2021 (UTC)
• Is biotin a single compound or a group of related ones like Vitamin B12?
  • Biotin is a single compound. David notMD (talk) 04:01, 18 January 2021 (UTC)
• "The frequency of marginal biotin status is not known" I don't understand this, is it possible to have other wording or add links to improve understanding?
  • Deleted, and section revised, with refs added. David notMD (talk) 21:59, 24 January 2021 (UTC)
• The final part of "cofactor biochemistry" seems to be missing citation?
  • Completely rewritten and properly referenced. David notMD (talk) 20:36, 25 January 2021 (UTC)
• The lead hints about genetic disorders that cause biotin deficiency, is this the same as the biotinidase deficiency described in #Deficiency? If yes, can you mention it? If not, what are the genetic disorders?
  • Details added. David notMD (talk) 02:29, 26 January 2021 (UTC)
• "This enzyme is responsible...": How about "Biotinidase is an enzyme responsible ..."  ?

Done. David notMD (talk) 02:29, 26 January 2021 (UTC)

• Biotinidase deficiency seems to be introduced twice, in #Deficiency and in #Metabolic disorders. Maybe better combine them? Or just describe fully in the first mention, and name it without intro in the second usage?
  • Resolved. David notMD (talk) 02:34, 26 January 2021 (UTC)
• the proteolytic degradation products of each holocarboxylase: Could you explain what each holocarboxylase refers to?
  • Resolved. David notMD (talk) 02:36, 26 January 2021 (UTC)

Per user talk, will continue reviewing after the nominator finishes making other updates. Thank you! HaEr48 (talk) 22:40, 16 January 2021 (UTC)

I will address the above bullets and indicate what other sections added or modified.

• • Added Diagnosis subsection to Deficiency. David notMD (talk) 04:01, 18 January 2021 (UTC)
  • Added Animals section. David notMD (talk) 17:59, 18 January 2021 (UTC)
  • Changed Bioavailability to Physiology, with subsections on absorption, metabolism, excretion, and conditions that affect biotin status. David notMD (talk) 22:00, 24 January 2021 (UTC)
  • Added Prevalence, diagnosis and treatment subsection to Metabolic disorders. David notMD (talk) 21:28, 26 January 2021 (UTC)
  • Biosynthesis revised to include ref for plants synthesizing and requiring biotin to function. David notMD (talk) 21:54, 31 January 2021 (UTC)

Other comments

I have found that this article has a minor flaw. It does not fit the Good Article criteria, part 1.a. and 2.b. According to 1.a., the article should be "clear", i.e. precise and have no vague or incomplete statements. It should not contain sentences that provoke further questions merely because these statements are formulated in such a way. According 2.b. of the criteria, an article should not contain "counter-intuitive or controversial statements that are challenged or likely to be challenged", unless there are citations from reliable sources to support these statements. I have found statements that are not clear and are likely to be challenged. See Talk:Biotin/Archive 1#Absorption for details. Maxim Masiutin (talk) 08:18, 29 January 2021 (UTC)

Maxim Masiutin has move more specific comments about the state of the article to Talk:Biotin and created an Absorption section there, so being addressed there. David notMD (talk) 18:52, 29 January 2021 (UTC)

I have addressed most of the Absorption questions. Will complete this evening. David notMD (talk) 21:10, 31 January 2021 (UTC)

Thank you very much! The current edit, on my understanding, resolves the issues (1.a. and 2.b.). Maxim Masiutin (talk) 22:14, 1 February 2021 (UTC)

Second round comments

• demonstrated an ability to update biotin. Is update here in the generic sense of "modify something to be more recent"? How does a molecule get updated? If there is a specific sense in biology, maybe link the appropriate concept?
  • "uptake", not "update" Fixed. David notMD (talk) 21:39, 9 February 2021 (UTC)
• Biosynthesis: does the synthesis by colon microbiota happen the same way as in the plants (as described)? Might it be worth mentioning explicitly?
  • Bacterial synthesis of biotin confirmed David notMD (talk) 21:39, 9 February 2021 (UTC)
• Biosynthesis: This section ends with the creation of dethiobiotin, but this molecule is not explained elsewhere. Is it the form that gets consumed by humans and animals? Or is there an additional step in plants that converts it into biotin?
  • Clarified that dethiobiotin converted to biotin in plants and bacteria by biotin synthase. David notMD (talk) 21:39, 9 February 2021 (UTC)
• Move the linking of biotinylation to the first mention.
  • I cannot locate the first mention. What section? David notMD (talk) 11:05, 10 February 2021 (UTC)
    • @David notMD: The #Definition section mentions it first HaEr48 (talk) 03:21, 11 February 2021 (UTC)
      • The earlier appearance of biotinylation is now the Wikilinked one.
• "range of 10⁻¹⁴ to 10⁻¹⁵ M)": There is a stray parenthesis, or do you mean to add an opening one somewhere?
  • Typo, Fixed. David notMD (talk) 23:16, 8 February 2021 (UTC)
• The section "Use in biotechnology" mostly describes what happens after the protein gets biotinylated, but can we have more detail on the biotinylation first? How is it done, and how to avoid biotinylating the other proteins that are meant to be washed away?
  • Improved description of the process, based on existing refs. David notMD (talk) 18:19, 10 February 2021 (UTC)
• "diagnostic immunoassay blood assays that use biotin-streptavidin technology" I think there are too many "assay" in this sentence?
  • Reworded David notMD (talk) 12:02, 10 February 2021 (UTC)
• is it valid to say "clinical trialed"?
  • Reworded to avoid. David notMD (talk) 23:16, 8 February 2021 (UTC)
• Hair, nails, skin: out of curiosity, do regulators require trials before allowing the marketing of a supplement for certain benefit? As in, is the marketing described in this section considered within the law?
  • Prior to my retirement I was an expert science consultant to US dietary supplement companies. Loosely, the rules are that a company cannot sell a drug until the U.S. Food and Drug Administration (FDA) says so, and a company can sell a dietary supplement until the FDA says stop. Clinical trials are nice but not necessary. As per the nature of a health claim, the law allows what are defined as Structure:Function claims on labels. These cannot be treatment claims. Labeling requires a specifically worded disclaimer statement. I have added more detail and a reference explaining this. David notMD (talk) 22:42, 8 February 2021 (UTC)
• The lead is supposed to be a summary of the article body. These items are mentioned in the lead without being the body, suggest adding them to the body
  • the etymology (maybe add into #History?)
    • Done David notMD (talk) 21:39, 9 February 2021 (UTC)
  • biotin transporter deficiency
    • Done David notMD (talk) 11:05, 10 February 2021 (UTC)
  • The history of neonatal screening
    • Done David notMD (talk) 21:39, 9 February 2021 (UTC)
  • The fact that the supplement treatment is lifelong
    • Done David notMD (talk) 21:39, 9 February 2021 (UTC)

Sorry for the review delay. A fine article! HaEr48 (talk) 23:31, 6 February 2021 (UTC)

The game is afoot! David notMD (talk) 01:22, 7 February 2021 (UTC)

I also have a problem in understanding the term "update" in the "absorption" section. Maybe use another term, easier to understand, or use a longer explanation that layman readers understand what does "update" mean? Maybe write the other way using the term "update", or explain what does this term mean? Maxim Masiutin (talk) 16:35, 8 February 2021 (UTC)

See above. David notMD (talk) 12:03, 10 February 2021 (UTC)

Thank you, the term 'uptake' is clear for me. Maxim Masiutin (talk) 14:38, 12 February 2021 (UTC)

I think I have adequately addressed all the comments of the second round. David notMD (talk) 18:19, 10 February 2021 (UTC)

NOTE: Histone biochemistry now a separate section with more detail and a new ref. David notMD (talk) 10:12, 11 February 2021 (UTC)

Thank you for mentioning. I wonder if we need "In addition to the carboxylase functions described above" in this section? Unless there is a more specific relation between the two, this feels redundant because of course this section talks about another biochemical role of biotin. HaEr48 (talk) 02:44, 13 February 2021 (UTC)

Done. David notMD (talk) 04:01, 16 February 2021 (UTC)

Thank you very much. Maxim Masiutin, given that you have commented on this review, do you have further concerns? Otherwise I am ready to promote the article. HaEr48 (talk) 13:18, 17 February 2021 (UTC)

@HaEr48: Thank you for your excellent review of the article. My concerns did only relate to the "Absorption" section, but now the section looks great and I have no further concerns. It is now emphasized that how much is absorbed in humans is unknown, to avoid speculations, since I saw conflicting opinions. One low quality opinion, from a Biotin lab kit manual, mentioned that no absorption from bacteria at all is done in humans, but this opinion does not meet Wikipedia standards. This is probably a topic of current research, but no high-quality data that would have confirmed the absorption in humans also exist, at least I didn't see, although I have searched. Thank you very much again, and feel free to promote the article. Maxim Masiutin (talk) 16:48, 17 February 2021 (UTC)

Thank you. I have promoted the article because in my view it meets the GA criteria, and the nominator have addressed all my suggestions. Thank you very much for the fine work, David notMD, and sorry for the delay! HaEr48 (talk) 20:48, 17 February 2021 (UTC)

And thank you for your diligence. Without it, I would not have worked so much on the content that was in the article before I began the GA effort, nor focus on adding new sections. I will be submitting a DYK for this one. David notMD (talk) 22:00, 17 February 2021 (UTC)

Absorption

The first part of the "Absorption" section is not supported by any reference. It is not clear whether the reference [4] given twice in the end of the section also applies to the first part of the section.

It is mentioned "The intestinal enzyme biotinidase then frees biotin, which is then absorbed", but not mentioned "where", i.e. at which part of the intestine it is absorbed: in the small intestine or in the large intestine or in stomach, etc.. There is a further mention, in a few sentences later, that "absorption across the colon wall is minimal". It is not quantified what means "minimal" in exact figures or in comparison to what, and whether this "minimum" it is enough to satisfy the needs of a human. How much biotin is absorbed this way? Also, it is not mentioned whether bacteria merely synthesize biotin that is protein-bound to this bacteria and further require biotinidase to free it, or it is secreted and free-to-absorb form. How are the measurements of biotin produced by bacteria done? Are these organisms are merely cultured outside human and then all is melted to see how much biotin is there? In sentence "There is some speculation that resident bacteria in the large intestine secrete biotin" is not specified who speculates that.

--- Maxim Masiutin (talk) 08:15, 29 January 2021 (UTC)

I will attempt to address these concerns as part of the GA review. David notMD (talk) 11:35, 29 January 2021 (UTC)

Ref added for colonic bacterial production and potential for absorption. Other parts revised. Still a bit of work left which I intend to complete this evening. David notMD (talk) 21:14, 31 January 2021 (UTC)

Thank you very much! Now it is OK. However, mention of the in vitro studies on Wikipedia is dangerous, some editors don't like it very much, and sometimes it's better to not mention at all than to mention an invitro study. Otherwise, they can claim that it is agains the rules of Wikipedia, or just delete such statements entirely to avoid problems. Let us keep the current edition and see how it goes. Thank you very much again for your edits. They now look very good for me. Maxim Masiutin (talk) 22:13, 1 February 2021 (UTC)