Talk:Spirulina (dietary supplement)

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Ridiculous Reference[edit]

At the end of the Health Benefits sector, there's a paragraph listing a random assortment of side effects and referencing Is this unsigned, anonymous website a good source of reference? John Holly (talk) 22:54, 21 March 2011 (UTC)


Spirulina is hella yummy!! The color of a flamingo's plumage is dependent on carotenes in the diet, including (especially) from shrimp. I've never heard of Spirulina coloring flamingos--surely zoos would use it instead of shrimp if they could, since it's cheaper.

The following article notes that Spirulina pigments are responsible for some flamingo's colors. See Chemical Composition - Pigments. Unfortunately, there's no directly related citation for this fact. 23:18, Sep 14, 2006 (UTC+1)


I was going to change it to this, but you biology types probably know it better than me. It removes all the kingdom links and such:

Scientific classification
Kingdom: Bacteria
Division: Cyanobacteria
Class: Cyanophyceae
Family: Oscillatoriaceae
Genus: Spirulina

Spirulina corakiana
Spirulina crispum
Spirulina labyrinthiformis
Spirulina laxa
Spirulina laxissima
Spirulina major
Spirulina meneghiniana
Spirulina nordstedtii
Spirulina princeps
Spirulina subsalsa
Spirulina subtilissima
Spirulina platensis
Spirulina tenerrima
Spirulina weissii

- Omegatron 20:22, Jan 22, 2005 (UTC)


Why are the nutrients in little groups? If the grouping is important, label each. - Omegatron 20:22, Jan 22, 2005 (UTC)

dont say it has B12[edit]

don't still say spirulina has vitimin B12 in light of all the new evidence.

I've been digging around, and it apparently contains some B12, but more pseudo-B12, hence less true B12 than some analyses say. (eg, J Agric Food Chem. 1999 Nov;47(11):4736-41, "The major (83%) and minor (17%) analogues were identified as pseudovitamin B(12) and vitamin B(12), respectively, as judged from data of TLC, reversed-phase HPLC, (1)H NMR spectroscopy, ultraviolet-visible spectroscopy, and biological activity using L. leichmannii as a test organism and the binding of vitamin B(12) to the intrinsic factor.") 07:39, 6 January 2007 (UTC)

Read this book[edit]

The best book about spirulina:

hardly--Niro5 19:20, 11 August 2006 (UTC)
A better book: Spirulina Platensis (Arthrospira): Physiology, Cell-Biology And Biotechnology. Perdita 23:10, 28 August 2006 (UTC)

RNA DNA[edit]

Spirulina is a VERY rich source of RNA and DNA

Bacteria have very little DNA and RNA, they are a simple and ancient creature and just don't need much plants have as much DNA in their chloroplasts alone, and Animals have as much DNA in their mitochondria. Furthermore, you don't need to take in DNA or RNA, your body can create it more than easily enough by itself. Even if you did need to take in DNA or RNA, unless you are eating rocks, everything you eat contains DNA and RNA. This article is sorely lacking any scientific credibility. If you can find a legitimate source, I'm fine with it, but otherwise it needs to go.

Niro5 15:06, 10 August 2006 (UTC)

I don't have a source for this but I would guess that Spirulina does have a lot of RNA at least, because bacteria have a very fast life cycle and therefore need to produce a lot of protein fast (spirulina especially has a lot of protein). Making proteins requires mRNA and ribosomes (which contain RNA as well). Also note that mitochondria have very small genomes (16 kilobases in humans - compare to an average bacterial genome of around 3 _mega_bases). Chloroplast DNA can be "bloated" compared to mitochondria, but is generally still smaller than a bacterial chromosome. 07:42, 13 April 2007 (UTC)

Sources[edit] This article should be a good source, and also it lists many other sources that can be used. I'll integrate it when i have the time.--Niro5 20:43, 26 July 2006 (UTC)

If you are on a crusade to champion the benefits of Spirulina, suppressing contrary evidence and not using proper sources will not hep you. A rigorous mind will see this page, and realize that there is no evidence and disbelieve it for that very reason. I suggest deleting every unsupported controversial claim and starting over again, but this time with evidence, not belief.--Niro5 12:37, 11 August 2006 (UTC)

Source (11) states that, "A more recently developed assay performed by a grower of spirulina has shown Spirulina to be a significant source of bioavailable B12."

However if you go to the link and read the full article, Dr. Todd Lorenz states: "Using the O. malhamensis assay in parallel to specifically measure human-active cobalamins the assay exhibits an average activity of 2.5 micrograms per 3 grams of Spirulina." But he provides NO REFERENCE for this study. You cannot look it up in any scientific journal. All other studies in Dr. Todd Lorenz's document have references, except the most important one that proves the point.

This is not a source. It is just a claim by Dr. Todd Lorenz, who works for Cyanotech, a maker of Spirulina. I could just as well make a claim that I did a study of Spirulina and it was loaded with B-12. Who would believe me, unless I could point to the source document?

Adamlove 03:02, 23 December 2006 (UTC) Adam Love

Source 11 is the reference for the statement in wikipedia; the basis for using the alternate assay is supported in the paper with two references. Just because it's not published in a journal doesn't mean it's "not a source." The wiki article states from the first that the B12 content is in dispute and gives references from both sides of the argument. Readers can follow the references and come to their own conclusions, just as you did. Perdita 17:41, 19 December 2006 (UTC)
That's a ridiculous argument, and very akin to what people say when they propose Intelligent Design in school curricula. "Just show them both sides and the kids will figure it out." This is an encyclopedia, not a message board. --Popoi (talk) 21:20, 12 February 2008 (UTC)

A legitimate scientific experiment is PUBLISHED SOMEWHERE. This is a reference to an experiment but it is not published, and not available to anyone for review, scientific or otherwise. There is no evidence that it exists. Would you use a drug based on a non-existent research paper?

Cyanotech suggests there is a legitimate study when there is no such thing.

I have altered the article to state that Cyanotech CLAIMS to have done an assay; this is the only accurate way to refer to it.

If other experiments (assays) are referenced in this article (for or against), they should also be tagged as claims, not legitimate studies.

Adamlove 03:02, 23 December 2006 (UTC)Adam Love

Are we sure that source 20 (about Shilianhua) is referring to the correct plant? This does seem right to me. (talk) 21:00, 13 May 2010 (UTC)

Berkeley Wellness Letter[edit]

It's good to show both sides of an issue, but I don't think this is an appropriate source. References should be made to published, primary sources. The claims here are no better than the claims on the other side in that they make no references of their own to support their assertions and are almost entirely non-specific. Further, their claim that "there’s no scientific evidence that blue-green algae can treat or cure any illness or has any health benefit," is simply not true. There are many sources to back up many of the claims.

In short, I agree with Niro5 that we ought to start over on this article and delete unsupported claims -- but the Berkeley Wellness Letter's claims are also unsupported.

Re-Name Article[edit]

The taxonomy in this area has been changing rapidly. The latest consensus I can find has two different genera, Spirulina and Arthrospira; the species associated with health food supplements belongs to Arthrospira, not to the genus Spirulina; however, the name the average person knows is "Spirulina."

I propose to re-name this article something along the lines of "Spirulina (Health Food Supplement)" and change the taxo box to the correct, current taxonomy for Arthrospira. I believe this should be done so that if someone wishes to start an article on the actual taxonomic genus Spirulina (which is not used in health food supplements), an easy distinction can be made between the two.

Alternately we could re-name this article "Arthrospira" and have searches on "Spirulina" re-directed here. Given the popularity of the name Spirulina, I would lean towards my first suggestion. Perdita 19:50, 29 August 2006 (UTC)

Nutrients and References[edit]

I've tried to document the nutrients included in Spirulina according to published research, and I've included the references. If you're going to change this area, you need to provide references to back up your changes. Recent changes did not reflect the references listed, and in some cases were simply wrong.

Concerning GLA, no mention is made of "recommended doses" of spirulina or comparisons to other sources of GLA. Primrose and other oils are extracts; spirulina is a whole food -- you can take as much as you want. The fact remains that spirulina is an unusually rich source of GLA. There are richer sources, but not many. The nutrients section makes no claims to spirulina being the "best" for anything; it simply lists what it contains.

Regarding vitamin A, spirulina contains beta-carotene which the body can convert to vitamin A, but spirulina itself contains no vitamin APerdita 00:02, 20 September 2006 (UTC)

I made a change to the wiki that has been changed back but without any comment. Does Spirulina contain Glutamic acid (flavor), Glutamic acid (amino acid), or not at all?—Preceding unsigned comment added by (talk) 16:14, 21 November 2008 (UTC)
Hi Anonymous. The edit you refer to with with spirulina containing MSG was probably vandalism or a mistake. When you said "Wikipedia needs to address the change", you're referring to yourself as much as anyone else. Previous editors have addressed the issue by removing the dubious statement. If you can find reliable sources indicating something more, or different to the article, feel free to make the change. Rather keep comments like that one on the talk page. Greenman (talk) 19:55, 21 November 2008 (UTC)


There is a production of High Quality Spirulina here in Greece, in Serres. The guy has so high quality spirulina that is the Official supplier of NASA and it's austronauts. Don't you think it's worth a mention? —The preceding unsigned comment was added by Everydaypanos (talkcontribs) 19:51, 20 January 2007 (UTC).

There is a documentary about the above production unit. You can view the video screener at youtube [ ]


This article reads more like an advertisement than an encyclopedic entry. --zandperl 01:05, 5 February 2007 (UTC)

Check it out from a year ago if you want to see an advertisement -- at least now all factual claims are cited with references. Perdita 18:13, 8 February 2007 (UTC)

While I agree completely with the need for reputable citations, I believe there is a strong place (especially here) for anectodal information, as long as it is presented as such. Much too little value is put on the cultural and historic usage and beliefs.Laurenbove 14:28, 17 October 2007 (UTC)laurenbove

I wanted to thank you for this excellent, neutral article. It definitely deserves the word "encyclopedic". Brief, but full of facts. I love Wikipedia for articles like this one her (sadly forgot my passwort, so I can't sign it, sorry) -- (talk) 15:50, 15 December 2007 (UTC)

Spirulina Allergies[edit]

I am allergic to spirulina but I see no allergy warnings or possible side effects listed in the article. This article truly does read like a advertisement.

I am going to add the allergy warning as I have read of at least one other person getting an allergic reaction from it. 00:37, 7 February 2007 (UTC)KnowledgeSeeker

I don't doubt what you say, but you must use cited references for material you add. Otherwise, I could say it cured my cancer and made me smart. Perdita 18:11, 8 February 2007 (UTC)
I totally agree with you. I'll look again for a reputable scientific source. I tried before but did not find anything worthwhile. 08:45, 11 February 2007 (UTC)KnowledgeSeeker
Ok, so my allergic reaction might have been caused by AFA as opposed to spirulina. See this link: . I guess I'll take the claim off if no one else minds or reports an allergic reaction also. 10:33, 20 April 2007 (UTC)KnowledgeSeeker
Is it useful to add an allergy warning to every single food that can occasionally cause allergies in a few people? Don't want to diss you as it sucks living with allergies, but as far as I know any food can cause allergic reactions in some people. Some people are allergic to onions or garlic or carrots or broccoli. Not sure if it is necessary to include in every single food source Wiki page that there can be allerci reactions to them in extreme cases?
Of course if there's a high incidence of allergies to this it would be relevant, not sure what the normal 'rate' of incidence in % is when it should be added but anyway, just wanted to add that :)
Cheers from another highly allergic person (yeah, even rice crackers).
Diederik —Preceding unsigned comment added by (talk) 11:11, 9 February 2011 (UTC)


The section titled "Neurotoxins" says that cyanobacteria can produce BMAA "under certain conditions". Well? What conditions? —Preceding unsigned comment added by (talk) 20:39, 27 October 2007 (UTC)

All of the references I could find indicated that dietary Spirulina was not one of the cyanobacteria tested for BMAA in the original study, which tested wild cyanobacteria, and at least one commercial producer of Spirulina has stated that their product tests negative for BMAA. I could not find any scientific reference associating BMAA with Spirulina. In my opinion, the Neurotoxins section of this article is misleading in that it implies guilt by association, and the section should be moved to the cyanobacteria article. However, I don't want to make a potentially controversial change without at least offering it for discussion first. To the commenter above, based on my limited research, I think that "under certain conditions" should be replaced with "some species of (but not Spirulina)" -- (talk) 03:26, 4 January 2008 (UTC)

Actually the citation pretty clearly indicates that the BGA which is harvested for the Spirulina product can be contaminated with other BGA species - ones which always produce toxins, under any conditions. In particular, harvesting from open natural waters (lakes, for example) can pick up dangerous levels of un-intended BGA organisms besides those which are supposed to be present in the Spirulina product/supplement. Cultured production is safer than "wild" collection. As the product is completely unregulated, there's no telling whether producers of "wild" harvested BGA test, know, or care that what's in it is uncontaminated. -- (talk) 01:21, 31 July 2010 (UTC)

Famous Advocates[edit]

Why is this part of the article? It sounds like a sales pitch or something... Why is it relevant to know specifically who has said good things about any dietary supplement? It makes the article look like a sheet from a sales catalogue. "don't take my word for it, look what these famous people has to say!". --Popoi (talk) 21:27, 12 February 2008 (UTC)

On second look, it's an advertisement, and I will remove it and the reference that links to a page that sells spirulina. --Popoi (talk) 22:43, 12 February 2008 (UTC)


I removed your link, it was pointing to a page that was under construction. Also, refrain from using all-uppercase as you were in the reference. It was not really clear how the page you linked to was relevant to the article. --Popoi (talk) 23:04, 12 February 2008 (UTC)

2007 book[edit]

this appears to have gathered studies together

ps a lot of the external links at the bottom of this article are shit

Misplaced references[edit]

Someone put a list of research papers within a section of the article without any explanation of what the articles implied. I have no doubt the papers have relevant material in them, but just listing them within the Wikipedia article is not acceptable. The correct usage is to state facts and justify them using references. I am pasting the list of papers here, so that anyone who wishes to use these in the appropriate way can incorporate the conclusions in the article.

<snip> Research articles: 1) Antihyperlipemic and antihypertensive effects of Spirulina maxima in an open sample of Mexican population: a preliminary report. Related Articles, LinksTorres-Duran PV, Ferreira-Hermosillo A, Juarez-Oropeza MA. Lipids Health Dis. 2007 Nov 26;6:33.PMID: 18039384 2) Efficacy of spirulina extract plus zinc in patients of chronic arsenic poisoning: a randomized placebo-controlled study. Related Articles, LinksMisbahuddin M, Islam AZ, Khandker S, Ifthaker-Al-Mahmud, Islam N, Anjumanara. Clin Toxicol (Phila). 2006;44(2):135-41.PMID: 16615668 3) Effect of Spirulina, a blue green algae, on gentamicin-induced oxidative stress and renal dysfunction in rats. Related Articles, LinksKuhad A, Tirkey N, Pilkhwal S, Chopra K. Fundam Clin Pharmacol. 2006 Apr;20(2):121-8.PMID: 16573712 4) Protective effect of Spirulina against doxorubicin-induced cardiotoxicity. Related Articles, LinksKhan M, Shobha JC, Mohan IK, Naidu MU, Sundaram C, Singh S, Kuppusamy P, Kutala VK. Phytother Res. 2005 Dec;19(12):1030-7.PMID: 16372368 5) Effects of a Spirulina-based dietary supplement on cytokine production from allergic rhinitis patients. Related Articles, LinksMao TK, Van de Water J, Gershwin ME. J Med Food. 2005 Spring;8(1):27-30.PMID: 15857205 6) Hypocholesterolemic effect of spirulina in patients with hyperlipidemic nephrotic syndrome. Related Articles, LinksSamuels R, Mani UV, Iyer UM, Nayak US. J Med Food. 2002 Summer;5(2):91-6.PMID: 12487756 </snip>

Cat's and Spirulina. My cat has once found a spirulina jar on the ground. It looks as if he clawed the lid open and ate as many as he could before we found him. I've just opened a jar and he smelt it from a couple of meters away he begged for it. Is this like catnip for a cat? —Preceding unsigned comment added by (talk) 03:54, 16 November 2008 (UTC)

Negative Effects / Arguments[edit]

Not to be a downer, but there's a section on proven positive health effects, but there isn't anything about the negative ones like potential allergic reactions or toxicity in high doses. Any input on that? I'll be doing some research, but it's in the article's best interest to maintain a balance rather than read biased. —Preceding unsigned comment added by (talk) 20:30, 8 July 2009 (UTC)

The Human Research section ends with a very odd, not to say nonsensical, paragraph, which according to the reference is derived from "There are no known side effects to spirulina, however the body may react to the consumption of it with symptoms including fever, dizziness, nausea, rashes or itchiness.[32]" If the body's negative reaction to the consumption of a substance is not to be considered a side effect, one has to wonder what, if anything, in the opinion of would qualify as a side effect? Speedwaystar (talk) 13:16, 24 January 2011 (UTC)

Article title[edit]

The article was renamed from Spirulina (dietary supplement) to Spirulina (organism) by User:Centrx without discussion, with the edit summary more accurate name. It's not - please discuss if you want to do something as drastic as rename an article! There's already an article for Spirulina (genus), and, as the first line of this article says, Spirulina is the common name for human and animal food supplements, not an organism. Greenman (talk) 14:45, 20 August 2009 (UTC)

I am here to agree wholeheartedly. The title should really be, simply, Spirulina. I might now be bold and fix this silliness. Huw Powell (talk) 03:03, 14 February 2011 (UTC)
It's a mess. I asked admins in general to help move these things around, since I can't delete redirects in order to move to them. Huw Powell (talk) 03:14, 14 February 2011 (UTC)

Claims about B12[edit]

I vote for the following paragraph to be removed:

«Tests done on Australian-grown spirulina by the Australian Government Analytical Laboratory (AGAL) show Vitamin B12 (cobalamin) levels of 659.1 ug / per100g [11].[dubious – discuss] A one gram tablet could provide more than three times the recommended daily intake of B12.»

The source does not seem to be very reliable: The PDF file is hosted on a website called "Australian Spirulina" which conveniently also has an online store where you can buy spirulina. The PDF is a photocopy of something that appears to be a report from the Australian Government's Department of Industry, tourism and resources. The sample appears to have been sent to the lab by the client. The report does not state which method was used to measure the B12 content. Nor does it say anything about whether this is active or inactive B12. TheLastNinja (talk) 21:37, 2 October 2009 (UTC)

Here are side effects: —Preceding unsigned comment added by (talk) 12:42, 16 November 2009 (UTC)

External Links[edit]

Sonerh (talk) 21:40, 14 September 2010 (UTC)Dear wiki-friends, I have spammed my website in external links area and it seems as if it is in blacklist now (probaby locak spirulina blacklist). I have rearranged the external links and now it should be fine. Could someone check it or help me to get my webpage out of spam list? The external links that are present now (the scientific abstracts) on Spirulina topic belong to me also. I have finally found a way to publish scientific documents except of my website. I am not expecting to get hits for that. I would like the information which are scientific, to be published anywhere. True scientific information should be available and for free for everyone. As you may check all the external links, there are no spam. I am a PhD student writing my thesis and publishing some information on my webpage, and try to do the same in wiki pages. please get me on whitelist for spirulina. no more mistakes from me anymore. See external links of spirulina: Please check this out. is mine also as, as well as,,,,,,,, etc. I JUST WANT TO publish true information in the right way and also it should be OK for the rules. This is just a misunderstanding so please get me on the whitelist. Sonerh (talk) 21:40, 14 September 2010 (UTC)

vague statement[edit]

I removed this statement because it is way too vague to be useful. If anyone wants to summarize the results of the cited study and add it back it, that might be helpful. "See 2010 published study: Maria Kalafati; Athanasios Z. Jamurtas; Michalis G. Nikolaidis; Vassilis Paschalis; Anastasios A. Theodorou; Giorgos K. Sakellariou; Yiannis Koutedakis; Dimitris Kouretas, Ergogenic and Antioxidant Effects of Spirulina Supplementation in Humans, Medicine and Science in Sports and Exercise®. 2010;42(1):142-151, concluding a positive effect occurred, although the mechanism was not well understood." Deli nk (talk) 21:32, 24 January 2011 (UTC)

Serious concern about poor sources[edit]

I'm concerned about the sourcing here. If Health Canada (a reliable source) in fact determined that spirulina contained no toxins, then we need to cite Health Canada directly, rather than through the lens of various unencyclopedic websites. The closest I can find is this fact sheet from Health Canada, which finds that spirulina-only supplements were not contaminated with microcystins, although other blue-green algae supplements were. MastCell Talk 21:37, 15 April 2011 (UTC)

Addendum: actually, the sourcing for health-related effects of spirulina is pretty crappy across the board. I will work on improving it. MastCell Talk 21:39, 15 April 2011 (UTC)

B12, again...[edit]

The version online on 2011-05-20 had a few mistakes which had to be corrected:

  • The standard B12 assay, using Lactobacillus leichmannii, shows spirulina to be a minimal source of bioavailable vitamin B12.[9] → Not so. The abstract (and the full study, which I have access to) clearly show that 17% of a total corrinoid content of 329 µg per 100 g of dry spirulina is true B12. What Wanatabe et al. say in plain English in the abstract of the 2002 study is that the proportion is low, not that it is a minimal source. Those 17% are enough to contribute around 30% RDA in a typical 3 g portion.
  • Spirulina supplements contain predominantly pseudovitamin B12, which is biologically inactive in humans.[10] → Cf. above. 83% inactive, 17% active. 17% of lots = fairly lots.
  • Companies which grow and market spirulina have claimed it to be a significant source of B12 on the basis of alternate, unpublished assays, although their claims are not accepted by independent scientific organizations. → Not sure about that. There was something about an O. malhamensis assay somewhere. Have to find it...
  • The American Dietetic Association and Dietitians of Canada in their position paper on vegetarian diets state that spirulina cannot be counted on as a reliable source of active vitamin B12.[11] → They say that because spirulina "may contain B12 analogs", by which they mean, in pretty poor scientese, anti-B12. B12 co-factors would be a pretty good news and are also B12 analogs. Plus it means that they didn't take Wanatabe et al. into account. I added the reasons for their doubts to clarify their reasons.
  • The medical literature similarly advises that spirulina is unsuitable as a source of B12.[10][12] → [12] is a ridiculous reference. It's completely superceded by the study [9] by the same team a few years later. I therefore omitted that one. — Preceding unsigned comment added by Rdavout (talkcontribs) 23:59, 27 May 2011 (UTC)

Oops. Forgot to sign. Rdavout (talk) 00:16, 28 May 2011 (UTC)


I don't think your edit moved the article in a positive direction. Reliable sources seem pretty clear that spirulina can't be counted on as a source of vitamin B12. I'm not sure why you think we shouldn't convey this to the reader. You seem to be substituting your personal opinions for the statements of reliable sources, which is a no-no. If there are recent reliable sources which say that spirulina is a good source of B12, then it should be straightforward to cite them and I'll happily change my mind. In the meantime, let's stick with the available reliable sources rather than trying to spin their rather unequivocal conclusions. MastCell Talk 03:53, 28 May 2011 (UTC)
OK, sorry I had to edit to push the debate forward. I tried doing that keeping on the talk page of an article once and never got the least reply. In any case I don't think a full revert is the best solution. I think there is an added value to at least some of my edit proposals but unfortunately trying to condense my argumentation would result in a big block of text which would be unreadable for the average reader on the Wikipedia. But why not try that on the talk page after all?
I withdraw part of my further comment because I didn't like the tone I used. My head was bursting again after rereading my notes on the subject.
For the time being, I stick to the following:
  • The Vitamin B12 content of spirulina has been subject to much debate. → Is a a good intro, much more balanced than "is not considered". I think I am going to write to Watanabe's team on this point because only that would really clear the issue of the "not a reliable source". After all, if you refer to the full text, there clearly is true B12. Plus it has shown pernicious anemia correction in rats [1], albeit at a lower level than cyanocobalamin. If you then consider that that study did not consider the fact that indeed only 17% of B12 was active (as proved by Watanabe a bit later), that shows that the point was proven, on rats.
  • In consequence, Watanabe himself concedes in [2] that "van den Berg et al. (68) demonstrated that a spirulina-supplemented diet does not induce severe vitamin B12 deficiency in rats, implying that the feeding of spirulina may not interfere with the vitamin B12 metabolism. Further studies are needed to clarify bioavailability of spirulina vitamin B12 in humans." → I feel that the current version does not reflect the latest opinion of the man who nearly single-handedly launched the debate on cyanobacterial vitamin B12.
Now for the questions. I decided to withdraw the rest and email Watanabe himself (hoping he'll reply). I have a number of other questions on B12 to submit for other articles (B12 and eggs, B12 fortification, etc). I'll keep you posted.
The available data bothers me.
When I read Watanabe, it seems to boil down to "A majority of cyanobacterial B12 is inactive. Thus it isn't a good source." But when I read the data, I fail to see the difference with eggs for instance. Reread what he says on eggs in [3]. In the full text, we learn that absorption is about 10%, that there is a paucity of B12 in them, etc. And in the conclusion, what do we have? Animals products, *including eggs* are an *excellent* sources of B12.
In a non-peer-reviewed study, I would have bounced to the ceiling to what looks like a sleight of hand. How can one indeed state that eggs is a way better source than source of B12 than spirulina while also affirming that bioavailable B12 is respectively 0.13 µg and 36 µg per 100 g. Literally speaking, it seems that 1.33 g of spirulina will cover the daily minimal allowance posted by the WHO whereas 370 g of eggs... 7 eggs. I must be missing something...
I understand beef liver doesn't get the same treatment given that B12 was first isolated from that in the first place. But then again, beef liver B12 has only 10% human bioavailability and total content of true B12 is 10 times lower than in spirulina. Are we just lacking a full-scale human study to prove the point? In that case, shouldn't it be mentioned? The Wikipedia article reads like the point was proven and it clearly isn't.
Rdavout (talk) 15:01, 28 May 2011 (UTC)

No reply after all these days. What a pity.
I'll include the original email I sent all the same:
Dear Dr. Watanabe,
The Wikipedia community is constantly reworking its articles to improve their quality and several articles concerning vitamin B12 would benefit from an agreed-upon expert opinion to arbitrage on a few issues which we could not solve by simple unambiguous referrals to existing peer-reviewed articles. The Wikipedia policy of "Neutral point of view" is indeed sometimes hard to achieve. Given your extremely high number of article contributions to the study of food sources of B12, it would absolutely marvellous if you could take a few minutes to confirm a few points.
  • B12 in fortified foods and other synthetic sources - A 1982 study ("Presence and formation of cobalamin analogues in multivitamin-mineral pills.",, H Kondo, M J Binder, J F Kolhouse, W R Smythe, E R Podell, and R H Allen) warns us that analogues in multivitamin pills may be an issue. In your review you quote a 2004 study on fortified breakfast cereal that gives in vivo evidence that B6 and B12-fortified cereals reduce homocysteine levels in the blood [4]. Do you feel that that study fully supercedes the former? In particular, at the best of our own very modest knowledege, we were lead to believe that B6 can confound such results and that this test is unsatisatisfactory to assess the B12 activity of a food in the presence of either folates and B6.
  • Understanding homocysteine impact tests - Depending on the former, does a homocysteine impact test constitute a good analysis of human bioavailability of vitamin B12 in foods in the absence or near absence of B6 or B9 content of the food).
  • B12 in cyanobacteria - You have identified a minor portion of 17% of the corrinoids in spirulina as vitamin B12 and then point out that "Further studies are needed to clarify bioavailability of spirulina vitamin B12 in humans.". Are you aware of any such study or ongoing study since 2006? What do you feel the existing evidence tends towards: recommending the general population not to consume spirulina? (=dangerous analogues); vegans and other people at high-risk of deficiency not to consume spirulina? (=dangerous to people in lack of proper B12); not disrecommending consumption but disrecommending consumption for the sake of obtaining a additional source of B12? (=useless source); not disrecommending consumption as a part of a diet but disrecommending use as a sole source (partial source, OK as a partial contributor of B12 to diet); and finally, for the sake of exhaustivity, recommending consumption as a proper source of B12 (= full usefulness as a potentially major contributor of B12 to diet).
  • B12 in eggs - the full text of your article seems to balance against the nutritional impact of eggs on vitamin B12 status given the paucity of vitamin B12 but the conclusions mentions it among animal sources as excellent sources of B12. A back-of-the-envelope calculation from your data seems to indicate that one would need to eat more than 7 eggs to achieve the WHO absolute minimum allowance of 0,48 µg. On the whole, would you therefore recommend inclusion among the sources of B12 listed on the Wikipedia?
  • B12 and vegans - Depending on your replies above, do you feel there exists any vegan-compatible sources of B12 to recommend on the Wikipedia? This would include typical foods, rare foods and synthetic-based B12 sources.
I hope you can help us with this and therefore promote the outreach of your results to the general public. In any case, thank you for your time.
Best regards,
... The absence of reply conforts my own personal opinion but I won't shove it on to others. I just hope a definitive study by another party will clear things up.

Rdavout (talk) 13:30, 9 June 2011 (UTC)


An editor added what appears to be a list of potential sources into the article instead of here. Not all of them are usable, but some might be.

Section moved here for discussion. - 2/0 (cont.) 23:47, 28 June 2011 (UTC)

Edit request from Brteag00, 3 July 2011[edit]

Please remove remaining spam at the bottom of the page (everything in a "Weblinks" section.)

Brteag00 (talk) 20:15, 3 July 2011 (UTC)

Done. Thanks for the alert.  Velella  Velella Talk   21:54, 3 July 2011 (UTC)

cyanobacterium & toxins[edit]

Hi there! I wanted to point out an error in a reference you used for Spirulina (dietary supplement). The study you're referring to applies to AFA (especially when grown in the wild), but not Spirulina. The reference states:

Spirulina is a form of cyanobacterium, some of which are known to produce toxins such as microcystins, BMAA, and others. Currently, no standard exists to regulate the safety of spirulina.[1]

Spirulina does not apply to the description "some of which". While it is true that AFA, microcystis, and spirulina are all types of cyanobacterium, spirulina has never been shown to cohabitate with microcystis (which produce microcystins) simply because these cyanobacterium thrive in very different conditions. Here's the reason why: AFA and microcystis both grow at a similar pH (between 8-9) whereas spirulina, when ready for harvest, is thriving at a pH between 10 - 11. These are a vastly different conditions which both spirulina and microcystis grow. Even if microcystis were introduced to an open-air spirulina culture, they would die within minutes because of the extremophile environment spirulina has naturally adapted to. As a algae grower myself, this was a deciding factor for me to raise spirulina -- very few forms of life, save scenedesmus, can grow alongside spirulina. Your reference however, would be appropriate to naturally grown AFA blue-green algae. Here is supporting documentation.

— Preceding unsigned comment added by (talk) 19:20, 27 September 2011 (UTC)

  • the above comment was left on my talk page, I don't have the time right now to research the provided references & make the edits myself --Versageek 14:33, 3 October 2011 (UTC)

Seconded. The incriminated sentence further more refers to the genus Spirulina, which is *not* the genus of "Spirulina" - ie. 'Arthrospira platensis/maxima. I thus removed the sentence(« Spirulina is a form of cyanobacterium, some of which are known to produce toxins such as microcystins, BMAA, and others. ») accordingly given that one month has passed with no action by anybody. Rdavout (talk) 00:20, 3 November 2011 (UTC)

Agree, there is no citation supplied that claims spirulina produces microcystins - the references refer to contamination while harvesting. I will remove the claim. Greenman (talk) 09:36, 31 December 2011 (UTC)


I also removed a reference on protein content provided by IIMSAM - this is not a recognized instutition although its name is very misleading and even it was, it is no *scientific* authority on the subject. Rdavout (talk) 00:23, 3 November 2011 (UTC)

B12 redux[edit]

Back on the issue of B12!

I feel it to be important to mark out that there *is* a controversy, not simply a universal agreement that Spirulina only contains inactive B12. The novel 2010 reference on methylcobalamin in B12 adds a bit of spice to the issue and should justify my new NOPV wording.

Quite frankly, the previous version was exceedingly skeptical and concealing. For the sake of proof how can one reference give "The standard B12 assay, using Lactobacillus leichmannii, shows spirulina to be a minimal source of bioavailable vitamin B12" when the paper in fact states (IMHO) that "The standard B12 assay, using Lactobacillus leichmannii, shows spirulina to containing mostly inactive compounds of vitamin B12 though the 17% active compounds theoretically add up to around 30% of adult RDA levels in a typical 3 g portion."

(Please don't reverse edit as is often done by the most vindicative. NOPV can only be obtained through consensus and the mediation of scientifically-literate relatively unconcerned third parties, not edit wars between bashers and groupies.)

Rdavout (talk) 00:37, 3 November 2011 (UTC)

I think we need to base our coverage on this site's sourcing policies. At present, expert opinion is extremely clear in that spirulina is not a reliable source of B12. The ADA and Dieticians of Canada position statement is the sort of reliable secondary source that we need to base our coverage on. We can't just cherry-pick the studies you think are most important, promote them, and editorially disparage the studies you disagree with. MastCell Talk 04:37, 3 November 2011 (UTC)

Frankly, aren't you doing the exact same thing? ADA statement is from 2003, new study from 2010. Let's have someone else intervene. I am grateful you didn't blast *everything* I contributed like last time [correction: you did but in several edits] but how can you justify removing:

  • For protein: More importantly, this marketing argument is based on a fallacy given that recommended consumption only add up to a few percentage points of the recommended daily allowance. → Are you a skeptic or what? This is not original research but a primary school level calculation.
  • For microcystins: Spirulina is a form of cyanobacterium, some of which are known to produce toxins such as microcystins, BMAA, and others. → Gosh, I'll whip you out the references a day I have the courage for this. "Spirulina" does not equate to *Spirulina*.
  • For B12, gosh... Did you even look at what I corrected? How can you *decide* to unilaterally remove the most recent reference on the subject. Etc

I'm reverting. Let us have an admin intervene for God's sake. — Preceding unsigned comment added by Rdavout (talkcontribs) 08:28, 3 November 2011 (UTC)

Editor assistance requested @ Wikipedia:Editor_assistance/Requests#Assistance_needed_on_Spirulina_.28dietary_supplement.29.

Rdavout (talk) 08:45, 3 November 2011 (UTC)

At present there doesn't seem to be much controversy about spirulina's B12 content. Besides marketing claims (many of which predate the studies) and this reference [1]. mentioned in the one edit, which I can't access, there doesn't seem to be any evidence that spirulina is a good source of B12, while there is a body of evidence indicating the opposite. Greenman (talk) 09:52, 31 December 2011 (UTC)


Regarding this edit, the original pubmed source makes the claim that "BGA products and other dietary supplements are regulated by the U.S. Food and Drug Administration (FDA) under the 1994 Dietary Supplement Health and Education Act (DSHEA) (46).", which supports the new edit and invalidates the original claim. I will restore the new claim using both citations, the new generic one, and the original source that makes specific mention of spirulina. Greenman (talk) 09:25, 31 December 2011 (UTC)

That's a very disappointing edit. You've read the source? The final paragraphs clearly identify the virtually unregulated dietary-supplement market in the U.S. as a concern with regard to spirulina and other blue-green algae supplements. The concluding paragraph of the source reads:

Many consumers of dietary supplements and other alternative health care products assume that these products could not be sold without the absolute assurance of safety. Unfortunately, because of the regulatory limits on the FDA that are imposed by the DSHEA, this is not the case. As our work with UKL BGA demonstrates, the dietary supplement industry is largely self-regulated, and assuming that these products are entirely safe may not, in fact, be a safe assumption. ([5], emphasis mine)

So it's deeply misleading to the reader to boil this down to "spirulina is regulated by the FDA". That's a lie by omission, and a misrepresentation of the source by any standard. I assume there's no intent to misrepresent the source, but this needs to be fixed. MastCell Talk 06:29, 2 January 2012 (UTC)
Please read WP:AGF especially regarding "lie by omission" and "intent to misrepresent".
I agree that Because spirulina is a dietary supplement, the United States Food and Drug Administration does not regulate the production and quality of the product. Currently, no standard exists to regulate the safety of spirulina in the U.S. is more accurate than Like other dietary supplements spirulina is regulated by the FDA. However, it implies that spirulina is unregulated in the USA, which is what the other editor and I read it as. An improvement would be to state that spirulina is regulated as a dietary supplement in the USA, but that no safety standard exists etc.
Please provide a source for the implication that spirulina produces toxins such as microcystins, BMAA, and others. To my knowledge this is false. Spirulina being contaminated with them, which I read the study as being about, is different to spirulina producing them. And if other cyanobacterium produce them, but not spirulina, that's like saying "carrots are a plant, some of which are deadly poisonous". True, but misleading.
Please explain why you feel The U.S. National Institutes of Health describes spirulina supplements as "possibly safe" for adults, provided they are free of microcystin contamination, but when contaminated by microcystins "likely unsafe" for children as they are more susceptible to the toxins which can contaminate spirulina supplements. is an improvement on The U.S. National Institutes of Health describes spirulina supplements as "possibly safe" for adults, provided they are free of microcystin contamination, but when contaminated by microcystins "likely unsafe" for children. The former is hideously badly written. After two mentions of microcystin contamination there's little need to explain yet again that it's the toxins that will be harmful to children. In fact, on further reading, I suggest The U.S. National Institutes of Health describes spirulina supplements as "possibly safe" for adults, provided they are free of microcystin contamination, but, when contaminated, "likely unsafe" for children as an improvement.Greenman (talk) 10:16, 2 January 2012 (UTC)
I've tried to address your concerns here. I rewrote the badly written sentence conveying the NIH website's recommendations. I clarified that spirulina may be contaminated with microcystins, rather than producing them directly. I've also expanded a bit on why microcystins are a concern, to reflect the cited source. MastCell Talk 00:50, 3 January 2012 (UTC)

False Reasoning Implied[edit]

In the section about "Protein and amino-acid content": "Spirulina contains about ... from legumes.[2][7] Overall, while spirulina is often marketed as an excellent source of protein, it is no better in this regard than milk or meat (in that they are all complete proteins), and is approximately 30 times more expensive per gram of protein."

I have two problems about that passage:

1 - The fact (of the cost), even if sourced, cannot be interpreted as the paragraph strongly seems to suggest. It starts arguing that it is no better as source of protein than milk or meat (which is a true statement, in general, and something not relative, which is very well explained by the observation inside the brackets) and then goes on about the cost, which is a different matter! The cost is relative to Economies of Scale! If Spirulina is 30x more expensive to produce *now*, it´s certainly not possible to affirm that this is not subject to change. And the text must reflect that relativity. But thinking about that cost data certaily leads me to wonder... 2 - What about the development of the cost argument itself? I´m not saying the source is wrong (but they could really have written that way to simply defend a cultural/commercial/convenient interpretation, which i´m not criticizing, but I am willing to avoid such interpretation to leak inside Wikipedia which is really about Science not needing permission to think), but looking at it biologically, what is more efficient, naturally, at generating this biomass we can use, chicken or algae? I´m not denying that society eats meat and it won´t stop, i´m just trying to get my values right - last time I checked we had something of a pyramid, you know, where top feeders required more energy, etc. Doesn´t the algae grows faster and more efficiently than chicken? I certainly thought so! What about the Wikipedia´s article about protein? It didn´t listed meat in the percentages where it lists spirulina right at the top, with more than 60% content, and i looked up chicken breasts in the article and it´s apparently 24 grams protein for 100 grams of breast. How much is 100g of Spirulina, and what the protein percentage? So, anyway, it seems very untrue to me, at this point, to consider Spirulina a priori costlier to produce than chicken, since in nature itself, it seems that algae win the numbers. It follows that the cost difference *must* derive mostly from our own organization, consumption, economy, etc, human transformation of it´s environment.

I´m proposing to edit it to:

"Spirulina contains about ... from legumes.[2][7] Overall, while spirulina is often marketed as an excellent source of protein, it is no better in this regard than milk or meat (in that they are all complete proteins), and is approximately 30 times more expensive per gram of protein. It could be argued, nevertheless, that such a high cost is due to Economies of Scale (link here). As all algae, Spirulina grows very fast and does Photosynthesis (link here). Of many others natural sources of complete proteins (link here), Spirulina ranks as one of the richest, along with Tempeh, Whey Protein and Meat." — Preceding unsigned comment added by Hoenen.felipe (talkcontribs) 19:19, 13 January 2012 (UTC)

No one has yet responded, although some editor/s have tried to remove the piece and been reverted. I agree in part, but mainly the figure of 30 is highly dubious, and is not backed up. It seems little more than a researcher's personal experience. Spirulina, milk and meat prices vary worldwide. Another source I found indicates a price differential of 4[2], and is at least specific to US currency. Doing a quick online price comparison now, I find steak at R70/700g, spirulina at R92 for 200g. In other words, the steak is R70 for 140g of protein (20% protein) and the spirulina R92 for 120g of protein (60% protein). I don't suggest expanding the piece to include this - it's personal research based on two expensive sources, but without a cumbersome discussion of economies of scale, or the vagaries of international pricing, the price comparison is nonsensical so I suggest it be removed. Greenman (talk) 22:56, 7 February 2012 (UTC)
The material/context on spirulina's protein content and relative cost are taken directly from a reliable secondary source (the U.S. National Library of Medicine). It sounds like you are proposing to water down, spin, or completely exclude this content because you personally disagree with it. Am I missing something? Because your proposals seem to fly in the face of this site's fundamental content policies. MastCell Talk 23:09, 7 February 2012 (UTC)
Let's ignore the conspiratorial insinuations, but yes, the figure of 30 needs to go because a) it has no context. It's like saying "the literacy rate is 60%". Yes, perhaps in some countries, some cities, at some point in time, but without any context it's entirely useless b) it's not backed up at all and seems to be little more than the author's back of a matchbox calculation. I have provided another source that gives a figure of 4. Do you dispute this? I'm sure you would agree that using a Shakespearean scholar as a reliable source for medical claims would not be acceptable. Nor is using a medical source for an economic claim, especially when there are no studies and no data. Greenman (talk) 00:00, 8 February 2012 (UTC)
There's been no opposition to this, so I will makes the suggested changes. Greenman (talk) 19:48, 26 February 2012 (UTC)
I opposed it. The material comes directly from an independent, reliable source. Your rationale for removing it is that you, personally, don't agree with it. That's not a good reason. MastCell Talk 06:33, 27 February 2012 (UTC)
Mastcell, you did not respond to the comment on the 8th of February. Not responding is not "opposing". Next you summarise my argument as I "personally don't agree with it". That, to put it mildly, is a very poor summary. You have ignored a source I've provided giving a figure of 4, and you've given no answer to my concerns about context. Do we compare the price of milk per gram of calcium to that of kelp? Why not? Milk boards and marketers around the world market milk as being high in calcium? Why not in this instance? At what time was the 30 figure applicable? What currency? What country? Do you really think meat and milk prices remain the same everywhere in the world? Do you really think meat, milk and spirulina prices don't change in relation to each other? Do you really think that meat and milk prices are identical per gram of protein everywhere in the world? So far all you've done is insinuate I'm trying to "spin" spirulina in some way and then claimed it's just that I personally don't agree with it. Please contribute constructively and respond to the concerns.Greenman (talk) 10:10, 27 February 2012 (UTC)
I don't want to argue our ideas about milk and meat prices; I'd like to talk sources. You cited this source, which appears to be a class paper written by a college undergraduate in 1996. Let me be clear: are you contending that this source meets WP:RS and should, in fact, take precedence over an article from the National Library of Medicine? MastCell Talk 19:42, 27 February 2012 (UTC)
If you don't want to discuss the prices then why do you insist on including the pricing in the article? Forget about sources then, it's obviously confusing you because I've been making multiple points, and you've been ignoring those inconvenient to your view. I'll focus on one issue. Why do you think the figure of '30' should stay in the article given all the flaws I've pointed out? Please consider this one question carefully. If you do have valid reasons for keeping it in, surely you think it should be improved and given a context? You can't simply argue "because it's in the source"! The source gives no context to the figure of 30, which is unsatisfactory for use in an encyclopedia. If a reliable source said something like "the cancer rates of people who take spirulina are 5 times higher than those who don't", you cannot conceivably argue that the information should go in in that format. That's a tabloid headline, not something fit for an encyclopedia. Anyone actually looking for information would have further questions about what that statement means - how much, how long, who? It's the same with the '30' figure - it's meaningless without a context. The source doesn't provide any context. Greenman (talk) 01:27, 29 February 2012 (UTC)
Since material on Wikipedia needs to be drawn from independent, reliable sources, I think it makes sense to focus on sources in this discussion. The figure comes from an independent, reliable source, which is why I think it's appropriate to cite it in our article.

You objected based on your personal dissatisfaction with the source, and your personal price comparison. I didn't address those objections, because they're not particularly relevant from the perspective of this site's content policies.

You also objected because this source cites a different figure. As I said, I don't think that source (a 1996 class paper written by a college undergrad) meets this site's sourcing criteria, and so I don't think it's relevant to our discussion either. Where does that leave us? MastCell Talk 23:35, 29 February 2012 (UTC)

Mastcell, I am saying you can't simply unthinkingly respond "because it's in the source" and yet that's just how you respond! Do you really not understand? Greenman (talk) 09:47, 1 March 2012 (UTC)
You can't remove well-sourced material simply because you personally don't like or believe it. Do other reliable sources cite a different figure? A college undergrad's class paper from 1996 is not a suitable source, but if you know of better sources, I'm open to hearing about them. MastCell Talk 20:43, 1 March 2012 (UTC)

30 times more[edit]

The article contains the phrase spirulina protein is no better ... than milk or meat, and is approximately 30 times more expensive per gram of protein.' To me, that seems highly unsatisfactory, in that it makes a blanket claim that the worldwide price of spirulina per gram of protein is constantly 30 times more than the worldwide price of meat and milk, which must be constantly at an approximately equivalent price worldwide. Editor Mastcell, above, is of the view that it should remain in its current form since that's how it's formulated in a reliable source. Beyond the logical flaws of wording the comparison as permanent and applicable worldwide (as if it were a rule of physics as opposed to an economic condition), it's also an example of systemic bias, since even if this figure of 30 applies (or did apply - the source is unclear as to where and when this was the case, or even in which currency) to one part of the world, it certainly doesn't apply in mine today. Greenman (talk) 10:04, 1 March 2012 (UTC)

Having reviewed the source and having searched, unsuccessfully for other sources which would stand muster in Wikipedia and failed, and having also done some comparative food price reviews in the UK (which does not of course count in Wikipedia) the figure of 30 times looks about right (£13 for 100g of Spirulina[3] and £0.44 for 100g of good quality minced beef at today's prices [4] ) the Spirulina in this context contains a range of other constituents listed as Spirulina Powder, Firming Agent(Povidone), Sodium Carboxymethylcellulose,Anti-Caking Agents (Silicon Dioxide, Magnesium Stearate), Bulking Agent (Dicalcium Phosphate),Chlorophyllin so it is impossible to calculate available protein equivalence.
As noted above, none of this is usable as a reference but it does indicate that the reference quoted remains robust in March 2012 and I see no reason to doubt it or to change the article text.  Velella  Velella Talk   11:16, 1 March 2012 (UTC)
If the concern is that we're implying a global relationship, that seems easily solved by editing the sentence to read that spirulina is no better than meat or milk, and is approximately 30 times more expensive in the U.S. MastCell Talk 20:59, 1 March 2012 (UTC)
Thanks for your research Velella. MastCell, yes, adding in the US that would be an improvement, as addressing the global issue tackles part of the problem (but not the temporal - ie in the US in 2011 would be better). However, I can see no mention in the source of the data applying to the US. The source has no information about where or how this figure was arrived at, or when and where it applied. Let's put it this way. First, WHY is this price comparison necessary in the article? Do we need to compare the price of omega-3 oils in flaxseed to that in fish? Do we need to compare the price of calcium in milk to that in kelp? Please answer that question thoughtfully. What does it add to the article? Then, if there is a good reason to keep the comparison in, I would argue firstly that an attempt needs to be made to improve it as per the start Mastcell has suggested, by finding more complete sources, and secondly, that if it cannot be improved, it needs to go, as it is meaningless in its current form. Greenman (talk) 00:53, 2 March 2012 (UTC)
If there are no arguments for keeping it in and no new data then I will remove the comparison. Greenman (talk) 20:42, 11 March 2012 (UTC)
Wow. You just heard several arguments for keeping the material, from both me and another outside editor. Or perhaps you didn't hear them, but nonetheless they exist, and it's inappropriate to keep trying to remove this relevant, appropriately sourced material despite objections. You've already gotten some outside input from Velella in this thread; if you want more, then I will ask at WP:RS/N, WP:MED, or WP:RfC, but don't keep removing the material once a week and pretending that there are no objections, please. MastCell Talk 17:32, 12 March 2012 (UTC)
Mastcell, wow, indeed :) You are completely out of line here. Firstly, I did not remove the content. I have not removed it in ages since you first raised concern. We were (at least I was) discussing it. Since there was no opposition to my most recent points I have to assume they were accepted. If I were to wait forever we'd never get anywhere. So please retract your false "once a week" claim. I realise you may be too busy reverting changes elsewhere to have time to read, much less follow and respond to, a discussion, but it's really not hard to see that the content has not been removed. Secondly, a discussion has to involve more than one person. I debunked (in my opinion!) your arguments to keep the status quo, and invited a response. You had none, but now come back with... precisely nothing. Well, actually, something entirely false and "Wow", which is rhetoric, not an argument. It appears no one has much interest in this article, and your interest is limited to keeping it in its current disappointing form and you are incapable of or unwilling to see any problems with it. I would welcome the contributions of other editors. Greenman (talk) 18:33, 12 March 2012 (UTC)
We got a contribution from another editor; in this thread, Velella supported the inclusion of the material in question. Thus it's a bit mystifying to hear you repeatedly assert that there are "no arguments for keeping it in". I articulated my reasoning. I understand that you believe you've "debunked" it, but from my perspective you've repeatedly offered the same editorial argumentation without one single reliable source to back your personal viewpoint. It looks to me like you're just not listening; why else do you keep repeating your personal viewpoint, without a single supporting reliable source, and then asserting that there are "no objections"?

If you'd like me to reiterate my request for sources every time you comment, then I will, but it seems a bit silly. On the other hand, I'm open to discussing actual reliable sources anytime, and open to changing my position on the basis of such sources. MastCell Talk 22:40, 12 March 2012 (UTC)

The definition of you're just not listening indeed :) I have accepted Velella's personal research, which seems to indicate that that the comparison is valid in current-day UK, but it doesn't add much to the debate. I have asked for a retraction of a false claim. You ignore it. I ask you why we need the comparison in. You don't give one (I have pointed out why a mindless "it's in the source", which was the best you could come up with earlier, was not acceptable). I accept your suggestion of an improvement but point out that it's not what the source says (that the data is from the US). You don't respond. There's not much further to talk about if you're going to ignore what I say, make false claims, use hyperbole like "wow", accuse me of "spin" without reason, show an inability to develop a logical train of thought in an argument, disappear for ages without responding and then come back with nothing new to add, and generally don't contribute constructively towards improving the article. I have asked you repeatedly to read the discussion, attempt to follow it, and then respond. If you can't do this then let's get others more able to contribute constructively involved. Greenman (talk) 23:15, 12 March 2012 (UTC)
I take it, on the basis of your comment, that you don't have any additional reliable sources to bring to the table at present. Please let me know if you turn any up, and I'll continue looking as well. MastCell Talk 21:21, 13 March 2012 (UTC)

All you have to say to clear this dispute is to change the sentence to "According to U.S. National Library of Medicine, " ... blue-green algae is no better in this regard than milk or meat (in that they are all complete proteins), and is approximately 30 times more expensive per gram of protein"."Curb Chain (talk) 09:28, 15 March 2012 (UTC)

RfC: Is the "30 times more" price comparison satisfactory?[edit]

See the discussion above for the details Greenman (talk) 23:23, 12 March 2012 (UTC)

  • For reference:
Source: (from U.S. National Library of Medicine) Our text
You may have been told that blue-green algae are an excellent source of protein. But, in reality, blue-green algae is no better than meat or milk as a protein source and costs about 30 times as much per gram. ([6]) Overall, while spirulina is often marketed as an excellent source of protein, it is no better in this regard than milk or meat (in that they are all complete proteins), and is approximately 30 times more expensive per gram of protein
  • Satisfactory Although the text could be tweaked a little: "Overall, while spirulina is often marketed as an excellent source of protein, it is no better in this regard than milk or meat (in that they are all complete proteins), but is significantly more expensive per gram of protein (approximately 30 times more in the United States at the 2012 price levels)." Off course, sources should be added. Night of the Big Wind talk 11:31, 15 March 2012 (UTC)
  • 'Satisfactory Agree with Night of the Big Wind, although there is a paraphrasing concern here too (which I'm surprised no-one has commented on). So a more significant rewording is in order. I suggest that "marketed as an excellent source of protein is cut, to leave "Overall, despite marketing claims to the contrary, the U.S. National Library of Medicine found that Spirulina was no more biologically useful a protein than those found in milk or meat, which can be up to 30 times cheaper per gram." Something of that nature, anyway (please do correct any accidental changes of meaning there, none was intended). - Jarry1250 [Deliberation needed] 14:36, 22 March 2012 (UTC)
  • I am content with the version by Night of the Big Wind although I have reservations about the USA only quotation. As I noted above, the figure is consistent in the UK but it is difficult to get a good ref for that. I would prefer the version at the start of this thread  Velella  Velella Talk   18:04, 22 March 2012 (UTC)
    The use of the USA is just an example, and I should have added that. Adding a long list of the situation here, there and everywhere is not seriously improving the article. So I suggest a tweak from (approximately 30 times more in the United States at the 2012 price levels) to (for example: approximately 30 times more in the United States at the 2012 price levels) Night of the Big Wind talk 19:38, 22 March 2012 (UTC)
  • Can anyone find sources for the claim of "approximately 30 times more in the United States at the 2012 price levels"? The source listed makes no mention of location or time that I can see, hence my dissatisfaction. Without geography or time the claim is meaningless, and we have no source providing either. Greenman (talk) 21:18, 22 March 2012 (UTC)
    • The article was published by an arm of the U.S. National Institutes of Health, and is thus presumably U.S.-based. It was last updated in Dec 2011 (not 2012), and so it's reasonable to assign the price comparison to 2011. We don't need an independent source to confirm that pricing data published in the U.S. in 2011 do, in fact, apply to the U.S. in 2011. These are good-faith attempts to satisfy your objections, but it's starting to feel more like you're demanding a shrubbery, or just spitting in our soup. MastCell Talk 22:18, 22 March 2012 (UTC)
      • MastCell, I appreciate your good faith attempts, but I must remind you that Wikipedia is not about what you presume, but about what reliable sources indicate. So far all I'm seeing is an attempt to make a source say more than it does. I have asked you to point out where the source says that the data is from the US and from 2011, and all you can return is a presumption and yet more wiki-acronyms in the hope I'll go away. It's all very well to presume that the data is from the US, and is from 2011, but statements need to be backed up by sources that can be verified, not implications. It's equally reasonable to presume that the author used data from their state only, or simply checked one or two local sources, like Vellela and I did to get a rough approximation. Do you not see how ludicrous this claim in its current form is? A first year economics student would be sent packing if they submitted something like this. I fail to understand the contorted efforts to keep a meaningless and unsupported price comparison in the article. Greenman (talk) 22:26, 24 March 2012 (UTC)
        • Look at the side-by-side comparison at the top of this thread: I don't see any contortions there. Again, I think it entirely reasonable to infer that pricing data published by a U.S. source in 2011 applies to the U.S. in 2011. This is a very rudimentary exercise of common sense, and I think your demands are unreasonable in the extreme. MastCell Talk 23:39, 24 March 2012 (UTC)
        • Are you serious, Greenman? Do you really think that American scientist, publishing in an American magazine, will do a price comparizon in, let's say, Ghana, Paraquay and Vanuatu? Night of the Big Wind talk 00:00, 25 March 2012 (UTC)
          • No, Night of the Big Wind, I did not suggest that the price comparison was made in Ghana. Perhaps you don't realise that the US has states, so the price comparison could have been made in Texas or in Alaska, which may have different prices for beef etc. I am simply questioning why an unsupported claim is being left in, and why loose assumptions are being made with a source. Greenman (talk) 02:01, 26 March 2012 (UTC)
          • I actually agree with Greeman. There's simply no need to make a specific claim that isn't verifiable when a weaker, verifiable claim is possible (see my previous comment for one example). - Jarry1250 [Deliberation needed] 22:43, 25 March 2012 (UTC)
            • The wording you suggested above in this thread would be fine with me. That said, I think this material is verifiable: it's attributable to a published reliable source which directly supports our article's content. That's the policy definition of verifiability. MastCell Talk 01:12, 26 March 2012 (UTC)
              • Thanks for your suggestion, Jarry1250. I would tweak it to "The U.S. National Library of Medicine stated that spirulina was no better than milk or meat as a protein source, and was approximately 30 times cheaper per gram.". "Approximately" is word they use, not "up to". "Despite marketing claims to the contrary" I would leave out, as the source makes no mention of marketing - it says "you may have heard", which is different. Greenman (talk) 02:01, 26 March 2012 (UTC)
                • Should be "more expensive" rather than "cheaper", but otherwise I don't really have a problem with that text. Well, actually, I do. The in-text attribution should be unnecessary in an ideal world - we typically omit it when a clearly reliable source makes a statement of fact which is uncontested by any other reliable source. But whatever. MastCell Talk 03:02, 26 March 2012 (UTC)


  • Support version listed in table at beginning of this thread, which I prefer. If it is found unacceptable, I weakly concur with Night of the Big Wind. St John Chrysostom Δόξατω Θεώ 02:33, 8 April 2012 (UTC)
  • Unnecessary detail - I do not think the number 30 will make or break the article. I'd support something more general than the RfC proposal and more emphatic than NotBW's otherwise well composed suggestion: "Overall, while spirulina is often marketed as an excellent source of protein, it is no better in this regard than milk or meat (in that they are all complete proteins), but is significantlymany times more expensive per gram of protein." Jojalozzo 14:30, 9 April 2012 (UTC)

Just because someone said it doesn't make it relevant. If WHO states that calcium in almonds is no better than calcium in milk and it costs 80 times more would it be in the almond article? Wikipedia isn't meant to have advertisements, and the statement in the article just reads as a rebuttal to an advertisement that isn't present. Further, the protein price comparison is irrelevant because very few people would consume spirulina as opposed to beef primarily on the protein basis. They'd probably consume spirulina because per 100 grams of protein when compared to beef they don't get as much saturated fat, or they get more zinc for their protein dollar or whatever. Haven't edited anything in a few years so can't remember my wiki name or details... but just surprised that this comment is in this article — Preceding unsigned comment added by (talk) 22:17, 25 September 2013 (UTC)

It's also very unclear if the whole 30 times thing is referring to per gram of the product or per gram of protein, as these would have very different values. I think it is very very wrong if we're looking at protein costs (what would be the point in looking at anything else). I live in Australia, and I can get 1kg of spirulina (1000 1 gram pills) at a chemist for $30AUD. With spirulina at about 60% protein that works out to approx. 5cents per 1 gram of protein. Milk has about 3.4 grams of protein per 100mL, so to get the equivalent 5cents of protein for milk it'd work out to be $1.60 per 1L of milk. Milk is definitely not 30 times less than this (which would be 5cents a litre!) I don't know how prices compare in US, but I wouldn't imagine they are completely different. My guess is that if the 30 times was based on anything, and not just plucked out of the air, it was some tiny amount of spirulina (20 grams per container) at an over-priced health store. In this case you should only compare it to buying 20 grams of milk at an over-priced health store and not large size bottle at a normal store. — Preceding unsigned comment added by (talk) 06:18, 18 October 2013 (UTC) Sorry I realised that it is actually 400 grams I get for $30 not 1kg. So this makes Spirulina 12.5cents/gram of protein and if milk protein was the same cost it'd be $4/L. Milk is certainly cheaper than $4/L but not 30times cheaper (which would be 13c/L - which is ridiculous). — Preceding unsigned comment added by (talk) 06:39, 18 October 2013 (UTC)

As discussed above, the claim in the article is obviously total nonsense. You and I can look at the prices and see they're clearly wrong, and any high-schooler would want to know what data was used, what time period, what area. None of this information is provided in the source, and it's clearly a back of a matchbox calculation. However, since it was made by a "reliable source", so editors here will keep re-inserting it some other reliable source bothers to repudiate it, which is unlikely to happen anytime soon. This article is a great lesson in the Wikipedia principle Wikipedia:VNT, and the need to read things sceptically, following the sources, as it contains an obviously false statement, but one however that is verifiable. Greenman (talk) 08:57, 19 October 2013 (UTC)


  1. ^ A. Kumudha, S.S. Kumar, M.S. Thakur, G.A. Ravishankar, R. Sarada (2010). "Purification, identification, and characterization of methylcobalamin from Spirulina platensis". Journal of agricultural food chemicals 58 (18): 9925–30. PMID 20799700. 
  2. ^
  3. ^ Holland and Barrett Spirulina offer
  4. ^ - Tesco minced beef


Does anyone have a reliable source for the spirulina's protein digestibility (PDCAAS)? Some unreliable sources give it a value of 1, but I can't find a reliable source for this. In this case, spirulina would then have an equivalent rating to milk and soy, and a slightly higher rating than beef. Greenman (talk) 23:42, 7 February 2012 (UTC)

Based on the amino acid values listed here, spirulina appears to be limited by lysine which is required at 58 mg/g of protein (Protein Quality Evaluation, Report of the Joint FAO/WHO Expert Consultation on Protein Quality Evaluation, Rome, 1990). The value listed here would only give it 53 resulting in an amino acid score of 91. Assuming it is completely digestible it's PDCAAS would be 91 if it is not then it would be lower.

Spirulina Quality-related safety issues -- Information Suppression?[edit]

I recently added some new references to the "safety issues" section, which contained a discussion that seemed to be driven entirely by one article (Gilroy), and was mainly based on _speculation_ that appeared in that article about possible health risks due to very low levels of microcystins detected in some Spirulina samples. I added seven references, all from peer-reviewed journals or other authorities. Almost all of the text I added has been cut cut out, including but one of the references, and now the page is locked, presumably because of my edits. Cut out: references showing that the microcystin levels found in almost all Spirulina samples were well below that declared safe by the Oregon Health Department, that the FDA has declared some Spirulina brands to be GRAS, that dozens of animal high-dose, long-term, and even multi-generational animal studies have shown no harm, and that Spirulina has been shown in multiple studies to _protect_ against liver damage. Can you seriously justify removing these references in view of what is being claimed in the section? They are obviously relevant, and any reasonable person would agree that the public ought to be able to see this information. I did not remove anyone else's references, or change the meaning of the other text, nor would I. What gives? FarmerOnMars — Preceding unsigned comment added by FarmerOnMars (talkcontribs) 22:49, 30 April 2012 (UTC)

Actually, editors here often delete others work for various reasons... that's what you should be focusing on. Ask the editor what the reason was for removing the information. To suggest as a new editor that "information suppression" is occuring is... well, rather touchy. The other thing is that I notice on your talk page that you are a "phycologist working in the NASA OMEGA algae biofuels project, as well as several other algae-related projects" (what is a phycologist?). You should probably review wp:conflict of interest and declare openly here what the exact nature of your work is -- and any potential bias. You should also tread very lightly on the kind of edits you make here. Wikipedia does not allow original research. And no editor with a conflict of interest should expect to have free reign here. Good luck!842U (talk) 23:09, 30 April 2012 (UTC)
From the edit summary left by the editor that removed your contribution, it appears that your edits took the focus of the section off of contamination and quality control (which is the focus of the section). As far as I can tell the page protection was unrelated to your edits unless you've been editing from Toronto. Jojalozzo 23:26, 30 April 2012 (UTC)
There's decent evidence to the effect that spirulina itself is safe. However, the evidence also indicates that spirulina supplements can become contaminated with microcystins and other toxins produced by other strains of blue-green algae, particularly if grown with poor quality control. The point made by the sources (including the NIH and the Gilroy article) is that, in the US, it is difficult or impossible to be certain of the purity of a spirulina supplement, because the production of dietary supplements has been deregulated by law. It is misleading to strenuously downplay this concern, which is found in numerous reliable sources. Contamination with heavy metals is also a serious global concern, as the situation in China demonstrates. MastCell Talk 23:37, 30 April 2012 (UTC)
I very much appreciate this information and feedback. A phycologist is a scientist who studies algae, which is what I am. While I am happy to admit that I do want algae to get their fair hearing, I am in full support of the Wikipedia mission, do not expect free reign, and am happy to discuss these issues, learn the WP ropes, and ensure that the article hews as closely as possible to the current scientific understanding, with a neutral outlook. My edits all concerned references to authoritative texts (FDA, OHD, peer-reviewed journals, etc.), no "original research". I do agree that there is reason to be concerned about microcystin contamination of Spirulina supplements; the question is, *how concerned*. Whether something is mere "downplaying" or not is a matter of opinion; the honest approach is to put the relevant known facts beside each other, without spin, and let people form their own opinions. Consider the facts that have been removed from the article:
  1. The levels of microcystin found in the Gilroy study were, with only one exception, well below those considered safe by the OHD.
  2. The FDA, presumably well aware of these risks and any others (as that is their job), saw fit to give certain Spirulina products the GRAS label.
This is certainly relevant information for someone trying to decide what choices to make about taking Spirulina products; can you explain to me why this should be excluded from the article? Other information about studies relating to the safety of Spirulina can be put into a new section; the article at this point lacks references to the relevant studies. MastCell's statement that "There's decent evidence to the effect that spirulina itself is safe" is not really reflected in the article as it stands.
FYI, I haven't been editing from Toronto. Alas, I cannot contact the person who redacted my edits, as I can't yet get through the article lock, though I am working on making the necessary 10 edits (rest assured, on non-controversial topics!) so I will be able to do so.
Again, thanks for the feedback, it's starting to restore my faith in WP...

The subject of my masters degree thesis was a neurotoxin known as BMAA. It is produced by cyanobacteria and all known taxa of cyanobacteria have been shown to produce the toxin. The effects of the toxin are latent. BMAA causes protein aggregation in neurones and years and even decades after ingestion leads to neurodegeneration (alzheimers, parkinsons and ALS). The effects of this toxin would not show up in the short term but the evidence is strong to suggest its link with disease later in life. Read Cox PA, Banack SA, Murch SJ, Rasmussen U, Tien G, et al. 2005. Proceedings of the national academy of science of the united states of america 102:5074-8 — Preceding unsigned comment added by (talk) 13:47, 5 October 2013 (UTC)

Beta-Carotine / Vitamin A[edit]

Something has to be wrong with the Vitamin A content... If you research, you can read things like "Spirulina Vitamin A overdose?" and that it has 10 times more Vitamin A than carrots. Other sources say 30 times. You never know what's true. This pdf (for instance) says it has 70-170 mg per 100 gramm beta-carotine and the cryptoxanthin amount would be 10 mg.

So what's true now? And every source says something else about the beta-carotine content that converts to Vitamin A (retinol). Some say twice the beta-carotine content equals Vitamin A. Others say you need 12 times the amount???!? — Preceding unsigned comment added by (talk) 20:15, 17 February 2014 (UTC)

Nutritional value per 100g[edit]

Why is the sum of the mass of the items in this section more (a lot more)than 100g? Are some of the values incorrect, or are they not actually "per 100g"? — Preceding unsigned comment added by Ecornwall (talkcontribs) 18:57, 5 April 2014 (UTC)