# Talk:Riboflavin

There was a question previously if riboflavin was necessary for the synthesis of FAD in all living cells. Looking at the structure of riboflavin, and then flavin mononucleotide, and then FAD, I see no way around it. Even if riboflavin is not an essential additive in species X, they'll have to synthesize riboflavin to be able to make FAD. David M

I believe beriberi is the result of a B1 defficiency, not B2... According to [1], "deficiency syndromes are characterized by sore throat, swelling of mucous membranes, mouth and/or lip sores, anemia, and dermatitis" - this doesn't sound like beriberi to me. Of course, I could be wrong - I'm not a doctor. User:nyh
After a lot of time with what I believe is a wrong fact (the beriberi connection) in the text, I decided to mark this as a factual dispute. I hope that someone can help me verify the correct fact. Nyh 08:53, 10 Mar 2004 (UTC)

You're right, it's wrong. Beriberi is caused by thiamine deficiency. A riboflavin deficiency doesn't have any "disease" name to go with it, probably because it almost invariably occurs in combination with deficiencies of other water-soluble vitamins.  == Nunh-huh 08:58, 10 Mar 2004 (UTC)
http://en.wikipedia.org/wiki/Beriberi also shows it is B1 and not B2.  Bryan 13:28, 13 March 2006 (UTC)

The author has left me wondering what GM stands for in the sentence: "In processed foods it is very likely to be GM ..." I would have edited the article to make it less vague, except I am hardly an authority on biochemestry.

It stands for Genetically Modified, I believe; meaning it is produced by an engineered bacteria.  However, I'm not sure this is the best way to word that paragraph (and we need to clarify and wikilink something there). I'm not sure how to improce it either.RJFJR 01:22, Feb 12, 2005 (UTC)

I added a comment on this, I hope it's cool.

The designation "E101" appears twice in the article, but with no reference. I'm curious what it means. Anastrophe 05:23, 4 December 2005 (UTC)

I think a comment on the “bright yellow color” actually showing florescence under black light should be added.   This fact shows why this vitamin is used as a food additive (Because of it’s nutritional value, and it’s effectiveness as a natural dye)

"it is thought deficiency is common"
By whom? This needs a reference cited. Very doubtful it is correct, especially in Western countries.
Added clarification and reference. Mild deficiency common in third world countries that do not have grain fortification policies; uncommon in U.S. and Europe. Data for the U.S. from NHANES and WWEIA.David notMD (talk) 17:02, 11 February 2016 (UTC)

There seems to be a contradiction: the first sentence states that Riboflavin is easily absorbed, and water soluble, the last paragraph says that it is not, and is secreted in urin (turning it bright yellow) and is difficult to deliver in water as it is insoluble!?
any citation on this would be insightful.
this contradiction was added on March 23, 2004 if you look in the history
IS water soluble, but less so compared to other B vitamins. If not water soluble, would not turn up in urine! Commercially, most products are fortified foods (flour, bread, pasta) and tablet or capsule dietary supplements, so solubility problem sidestepped.David notMD (talk) 17:06, 11 February 2016 (UTC)

It's good to have a section discussing overdose conditions and symptoms in any page discussing a 'healthy vitamin'. If anyone has this information it'd be good to place it here.
Now covered under Toxicity. Riboflavin is considered non-toxic for the reasons given (increasingly poor absorption as dose is increased; efficient excretion by kidneys into urine; lack of identified adverse effects).David notMD (talk) 19:51, 10 February 2016 (UTC)

There seem to be a couple of factual discrepancies on this article. Some of the statements that are made, e.g. "Vitamin B2 is also required for red blood cell formation and respiration, antibody production, and for regulating human growth and reproduction. It is essential for healthy skin, nails, hair growth and general good health, including regulating thyroid activity," are not substantiated in the reference cited, and some other statements, e.g. "Any excess is excreted in the urine, frequently imparting a bright yellow color," seem to contain factual errors. Not being a biochemist myself, I don't feel confident making substantial changes, but are those statements valid? Katechen 20:48, 31 January 2007 (UTC)

Comment by User:96.230.31.114 moved from article:

Riboflavin was on the Nutrition facts of our Life Cereal box, we didn't know what it was, and decided to look it up. We still don't understand what it is.
I "translated" the page: simple:Riboflavin.  I hope this helps. --Slashme 14:09, 3 September 2007 (UTC)

It's stated that measuring erythrocyte glutathione reductase reports on riboflavin levels.  Any further comment/info on this? I have no reason to think it's incorrect, but it's clearly an indirect assay (presumably used in a standard clinical setting where more specialised analytical equipment is inappropriate?)  —Preceding unsigned comment added by 155.198.148.173 (talk) 20:54, 8 January 2008 (UTC) 
sreyhsegaef dvb Dg i dont no  —Preceding unsigned comment added by 64.66.92.50 (talk) 13:37, 27 March 2008 (UTC) 

Vitamin G redirects here. It should be mentioned, or better explained, in the article.--Srleffler (talk) 05:46, 2 October 2009 (UTC)

http://www.nicnas.gov.au/Industry/AICS/ViewChemical.asp?SingleHit=1&Chemical_Id=3685&docVer=
http://en.wikipedia.org/wiki/Flavin_mononucleotide
http://www.foodstandards.gov.au/newsroom/publications/choosingtherightstuff/foodadditivesnumeric1680.cfm
--222.67.219.51 (talk) 04:33, 2 December 2009 (UTC)

http://www.food-info.net/uk/e/e100-200.htm
--58.38.43.199 (talk) 05:42, 2 December 2009 (UTC)

Do you have a point, other than that you're confused? Yappy2bhere (talk) 00:01, 5 December 2009 (UTC)
Feb 2016: Text added in various places in attempt to make content clearer for people without a science background.David notMD (talk) 12:44, 10 February 2016 (UTC)

This is outside from text: {{Chembox Hazards poop| FlashPt=
Palapa (talk) 23:04, 22 September 2011 (UTC)

Thanks. The vandalism has been fixed.--Srleffler (talk) 06:08, 23 September 2011 (UTC)

The Image:Riboflavinspectra.jpg specified in the middle of the discovery section shows (eg. in Firefox and IE) no higher than the bottom of the infobox, which if the browser window is wide can be two sections lower. Do other users see this problems, and if so how do we fix it ? - Rod57 (talk) 23:36, 10 September 2012 (UTC)

I don't see the problem. Where is it that you want this image to be, vs. where it shows up for you? SBHarris 00:08, 11 September 2012 (UTC)
It is specified in the middle of the Discovery section which is where it would be logical and useful for it to be displayed; but if my browser window is wide it actually appears 2 sections lower so that the top of the image aligns with the bottom of the main infobox on the right. - Rod57 (talk) 23:18, 12 September 2012 (UTC)
But the spectra is a left thumb so I can't figure out how it gets to the right side of your display, where the infobox is. That doesn't happen on mine. Under the infobox on my display is the photo of fluorescent riboflavin solution in plastic tube. SBHarris 00:06, 13 September 2012 (UTC)

The statement, "Riboflavin deficiency has been implicated in cancer,[15]"  is not supported by the paper given in the footnote. The paper presents a complex situation regarding riboflavin and cancer.  It only suggests that riboflavin deficiency may increase carcogenicity in a very narrow situation.  In other cases the situation is more complex.  The statement misrepresents the content of the paper.  I suggest that it be removed.  7802mark (talk) 01:33, 1 January 2016 (UTC)
I agree, and did so. The cancer reference in question was a speculative review from 1973.  A search on more recent science lit did not find support for riboflavin deficiency increasing risk of any types of cancer.David notMD (talk) 05:17, 12 February 2016 (UTC)

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 revised in May 2016. 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 and mineral entries I have edited. Comments and improvements are welcome. David notMD (talk) 14:13, 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)

Shouldn't this article include a section on biosynthesis?  — Preceding unsigned comment added by 70.106.231.248 (talk) 17:58, 18 April 2017 (UTC) 

In looking at the leads for all of the vitamins, most have no mention of cost. Would these articles be better if none mentioned cost? Or if all used the same source? Vitamin C states 3-7 cents per 100 mg tablet, referenced to: International Drug Price Indicator Guide. Management Sciences for Health, Arlington, VA. 2016. Folate and Vitamin B1 cite the same source, but the hyperlinks do not work. Vitamins B1 and B2 reference a text without a hyperlink [Hamilton, Richart (2015). Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition. Jones & Bartlett Learning. p. 230. ISBN 9781284057560.] which appears to apply to hospital prescription pricing, as the costs are far higher than vitamin supplement pricing. My preference is for no mention of cost. David notMD (talk) 10:45, 5 August 2017 (UTC)

How much medications cost, especially those on the WHO List of Essential Medicines is important with respect to global health. Doc James (talk · contribs · email) 23:15, 5 August 2017 (UTC)

The article currently has "Riboflavin was discovered in 1920" but it does not mention where it was discovered. I have local notes that state "milk" which did not help me much because... what type of milk? I assume cow milk. Anyway, could the main article please also mention in what TYPE of milk it was discovered? 2A02:8388:1603:CB00:3AD5:47FF:FE18:CC7F (talk) 11:18, 4 November 2017 (UTC)

Checking refs, replacing very old refs with newer, ordering sections to be in sync with other vitamin articles, etc., as attempt to improve article so that it can be considered for upgrade to B-class. David notMD (talk) 18:41, 15 June 2020 (UTC)

Preparing article for GA nomination. All help welcome. 

This will be my ninth effort to raise a vitamin to GA. If this succeeds, that will leave vitamin B1, A, D and E. I dread tackling vitamin D because of its existing length and high level of ongoing editing. David notMD (talk) 13:29, 4 October 2021 (UTC)
Replacing old refs when possible, and removing refs that are not WP:MEDRS. David notMD (talk) 09:43, 8 October 2021 (UTC)
Diagnosis subsection refs are all old and all clinical trials, some quite small (n=6)!, so replacing with use of newer review refs if possible. David notMD (talk) 20:09, 8 October 2021 (UTC)
Causes subsection being updated and enlarged. Removed mention of several diseases or diet patterns or medications as causing low riboflavin, as literature searches did not confirm. David notMD (talk) 11:56, 11 October 2021 (UTC)
Absorption, metabolism and excretion section being updated and enlarged. David notMD (talk) 12:36, 25 October 2021 (UTC)
Sources table added from USDA website. David notMD (talk) 17:50, 30 October 2021 (UTC)

This edit replaced the previous version, here which was a bullet list with no sources. I used the NIH, LPI, and PubChem sources as main references, which are general, comprehensive, and plainly-written for a section with considerable underlying biochemistry (WP:NOTTEXTBOOK). Further editing may benefit from use of the LPI source which is a comprehensive review of riboflavin mainly in student-friendly language (I have no affiliation). Zefr (talk) 18:10, 15 October 2021 (UTC)

Some work still needed, but consider it close enough to nominate for Good Article review. All editors welcome to help improve the article. David notMD (talk) 13:12, 28 October 2021 (UTC)

Achieved GA on 9 December 2021. David notMD (talk) 10:58, 11 December 2021 (UTC)

Function 
Normal growth 
Deficiency symptoms 
Loss of appetite curled toe paralysis in chickens lower resistance to disease
Food sources
Whole grains (ruminants do not require supplements in their ration because they an make their vitamin B2 41.115.4.205 (talk) 10:31, 1 February 2022 (UTC)

This could be a section or subsection somewhere, but would require reliable source references. See Vitamin A for an Animal requirements section. David notMD (talk) 11:02, 1 February 2022 (UTC)

I've found that two rare genetic disorders are highly responsive to treatment with riboflavin, and I propose to add a subsection mentioning this. In fact, I had already added the subsection, but my edits were reverted. Here are the disorders:

Riboflavin-responsive exercise intolerance - discovered in 2016, drastic improvement on riboflavin. Only several cases thus far in the literature, but the link to riboflavin is self-evident, expressed in the name of the disorder.
Glutaric acidemia type 2 - the majority of late-onset cases benefit greatly from riboflavin, this is mentioned in a 2008 review ("Lipid storage myopathies", by Bruno et al) and a 2014 case series/literature review: ("Riboflavin-responsive multiple Acyl-CoA dehydrogenation deficiency in 13 cases, and a literature review in mainland Chinese patients" by Zhu et al). A quote from the 2008 review: Less severely affected patients might present with progressive muscle weakness and LSM mainly in adulthood and are responsive to riboflavin treatment (riboflavin-responsive MADD). A couple of quotes from the 2014 case series/lit review: Most patients with late-onset MADD are well responsive to treatment with riboflavin, which is also termed as riboflavin-responsive MADD (RR-MADD). Most patients with late-onset MADD can be totally or partly cured on treatment with riboflavin; hence, this clinical phenotype was called riboflavin-responsive MADD (RR-MADD).1, 5 Most cases of RR-MADD present with fluctuating muscle weakness, exercise intolerance, myalgia and dramatic riboflavin responsiveness; symptoms of cardiac or gastrointestinal disorders are occasionally observed in some patients.6 --CopperKettle (talk) 02:49, 7 July 2022 (UTC)
My opinion on this is that the references for rr-MADD justify adding that as a rare condition, but the evidence for RREI - a case study - does not meet MEDRS standards despite there being a Wikipedia article of that name. David notMD (talk) 12:29, 7 July 2022 (UTC)

We need a Chemistry tag for more description for Riboflavin.
For example:
Riboflavin has a benzene connected to 2 methyl groups, a ring with NH group and N group, connected by 2 Oxygen group. In between two rings is another cyclohexene with 1 nitrogen group and another nitrogen connected to hydroxyl side chains (in total of 4 -OH group)
I need a confirmed access to write the Chemistry tag, else someone will delete that and say something like "Do not add something that's unauthorized"
Cube26 (talk) 00:40, 16 July 2022 (UTC)

Is there any data of the amount absorbed via the active transport system for Vitamin B2? There is such data for B12 in the article Vitamin B12, but question is is there any data on the amount absorbed via the active transport system? Second question is what is the percentage of vitamin B2 absorbed by passive diffusion? Maxim Masiutin (talk) 10:40, 25 March 2024 (UTC)

Riboflavin is not found in which foods 
103.99.184.102 (talk) 05:44, 22 June 2024 (UTC)

Riboflavin is not found in which food 103.99.184.102 (talk) 05:45, 22 June 2024 (UTC)
The table shows examples of foods that are good sources and that are not. In addition, the reference for the table is to a government data table that can be searched for other foods. David notMD (talk) 10:33, 22 June 2024 (UTC)

The solubility of riboflavin in water is 0.07 g/L. Do this really count as water-soluble, like the lead says? --Nucleus hydro elemon (talk) 11:42, 29 July 2024 (UTC)

Per reference #3 (US NIH), all B vitamins are considered water soluble. The reference you cite has it as 70 mg/liter. The normal range of plasma riboflavin is 1–19 µg/liter David notMD (talk) 17:09, 29 July 2024 (UTC)