Talk:Creatine

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Archive[edit]

Educational video on creatine deficiencies[edit]

I added an educational video in the section about the Genetic Deficiencies. Can someone please help me understand why this is not appropriate? Thanks! Auract (talk) 22:43, 7 January 2019 (UTC)


lack of research = it's bad?[edit]

"Pregnancy and breastfeeding

Creatine cannot be recommended during pregnancy or breastfeeding due to a lack of scientific information. Pasteurized cow's milk contains higher levels of creatine than human milk.[24][25]"

The sentence essentially says that since there is a lack of research done, it must be bad. Seriously? — Preceding unsigned comment added by 99.236.136.206 (talk) 07:26, 26 September 2011 (UTC)

Dietary supplement labels often contain a statement that the product is not intended for use by pregnant/lactating women, or children. This is not to imply causes harm. Rather, it is an acknowledgement that clinical trials reported a safety evaluation have not been conducted in those populations.David notMD (talk) 19:08, 17 March 2017 (UTC)

Unsourced, etc.?[edit]

Is 99.233.126.11's [change of 2011-10-29T05:38:25] warranted? It looks like some made up text. --Mortense (talk) 10:35, 1 November 2011 (UTC)

Non-sensical sentence.[edit]

The following sentence makes no sense whatsoever. "A survey of long-term use gives the creatine content of several foods."

It appears to be the result of two unrelated half-sentences accidentally strung together. 109.149.158.177 (talk) 12:29, 12 April 2012 (UTC)

I agree; its poorly worded, and makes no clear meaning. Let's delete and ask whoever interprets it to discuss here. Thanks for posting the notice.--Jbeans (talk) 08:45, 22 August 2012 (UTC)

Proposed improvement to sentences[edit]

I propose that these sentences under the pharmacokinetics heading:

"The rest is eliminated out of the body as waste. Creatine is consumed by the body fairly quickly, and if one wishes to maintain the high concentration of creatine, Post-loading dose, 2-5 g daily is the standard amount to intake.[25][26][27]"

be replaced with these sentences (to improve the style, clarity and readibility):

"Any excess above this preset amount is eliminated from the body as waste. Creatine is consumed by the body fairly quickly, and if one wishes to maintain a high plasma concentration of creatine (post any aforementioned "loading dose" period), 2-5 g daily is the standard amount to intake.[25][26][27]"

109.149.158.177 (talk) 12:45, 12 April 2012 (UTC)


Additional sentence improvement proposal[edit]

I propose that this sentence under the Supplements heading:

"Both two studies reviewed in 2007 found no impurities."

be replaced with one of these two sentences (to improve readibility):

"Both of the two studies reviewed in 2007 found no impurities."

or

"Both studies reviewed in 2007 found no impurities."

Mattpengelly (talk) 23:28, 6 July 2016 (UTC)

Supplements[edit]

The article seems disingenuous in its positive description of creatine benefiting muscular development and performance in resistance training. The study cited in reference No.8 clearly refutes such benefits, yet it is not cited in the "Supplement" section. This reference No.8 is immediately available in full text, is very clear and informative and plainly concludes there were no measurable benefits of creating supplementation in a controlled, double blind study of creatine supplements and placebo in a a study of 30 participants in resistance training and creatine supplementation. Reference No.8!says it all, yet is left out of this section that plainly states that creatine supplementation does benefit users in resistance training. The references that are cited here, No.'s 20 and 21 are not available in full text, yet the abstract implies that creatine was not found to provide significant benefits in resistance training. It certainly isn't clear, and access to these articles costs between $35 and $64, making it prohibitive to check for interest. I wonder if the author read them? — Preceding unsigned comment added by 70.139.220.75 (talk) 02:49, 5 May 2012 (UTC)

The study in Reference #8 was performed on Creatine ethyl ester, an obsolete gimmick that was at one time touted by supplement manufacturers to be a superior form of creatine, but ultimately disproven and now makes up a very small percentage of the world's creatine production and sales. Using this study as evidence that creatine does not work, would be ignoring the hundreds of studies that show the most researched and popular form of creatine, Creatine monohydrate, has considerable muscle building and performance benefits for athletes and weight trained individuals. See Creatine supplements for a somewhat more thorough overview of the athletic benefits of creatine.Yankees76 Talk 20:26, 7 May 2012 (UTC)

nutritional sources??[edit]

in the article it says: "Given the fact that creatine can be synthesized from the above mentioned amino acids, protein sources rich in these amino acids can be expected to provide adequate capability of native biosynthesis in the human body." which are precisely these "proteine sources"??? please add a list to the article so you know what to eat! thank you! --HilmarHansWerner (talk) 19:53, 7 February 2013 (UTC)

Pretty much every protein source has L-arginine, glycine, and L-methionine. I don't think including a list of proteins that can biosynthesize creatine would be particularly useful, or needed. Yankees76 Talk

Creatine supplementation uses a pure form. It would be interesting to know more about the process that produces it. 92.25.5.8 (talk) —Preceding undated comment added 19:45, 13 November 2013 (UTC)

Pronunciation[edit]

I have changed the pronunciation transcriptions since they contained a diphthongized /-aɪn/ version which is at best very rare and highly likely non-technical. I believe the same should be done for all WP entries with same biochemistry -ine suffix. The sources I used are two of the best guides available for AmEng and BrEng, the Merriam-Webster (already used by the previous editor) and the Longman Pronunciation Dictionary. Neither of these sources show the /-aɪn/ variant, which is perhaps used by very few people who may be native speakers of English but are unfamiliar with biochemistry (in other words, an incorrect "spelling" pronunciation used by people who never say creatine). Incidentally, both dictionaries concur in listing the two acceptable pronunciations in the same order (as shown here).Viktor Laszlo (talk) 15:23, 22 May 2013 (UTC)

Health Effects[edit]

An analytical study published March 31, 2015 in the British Journal of Cancer conducted a population-based case-control study on the relationship between muscle-building supplements, including creatine, and the testicular germ cell cancer risk. Associations with Creatine, and other muscle building substances show a strong relationship between users, and testicular germ cell cancer (doi:10.1038/bjc.2015.26). Significantly stronger in early users. — Preceding unsigned comment added by Sooleymon (talkcontribs) 15:39, 23 April 2015 (UTC)

The following statement seems to be incorrect:

"Extensive research has shown that oral creatine supplementation at a rate of 5 to 20 grams per day appears to be very safe and largely devoid of adverse side-effects,[23] while at the same time effectively improving the physiological response to resistance exercise, increasing the maximal force production of muscles in both men and women.[24][25]"

Source [23] indicates that during a research with several individuals no evidence was found to substantiate a deleterious effect in the use of creatin for a short period of time. Also source [23] indicates that no research was conducted so far to evaluate the long term effects on the prolonged usage of Creatin in healthy subjects, thus, it is incorrect to say that:

"Extensive research has shown that oral creatine supplementation at a rate of a rate of 5 to 20 grams per day appears to be very safe and largely devoid of adverse side-effects..."

Moreover the "Extensive research misleads he reader to believe that several studies reached that conclusion, which in fact the author of the sentence is pointing to only one source.

The sentence should be modified to:

"One research has shown that oral creatine supplementation at a rate of a rate of 5 to 20 grams per day appears to be very safe and largely devoid of adverse side-effects for short periods of time..."

The scientific source [23] says the following:

"There appears to be no strong scientific evidence to support any adverse effects but it should be noted that there have been no studies to date that address the issue of long-term Cr usage."

Another possibility is to copy and paste the paragraph from the scientific article [23] and put it also in italic providing credit to the original source. — Preceding unsigned comment added by Raphael Calvo (talkcontribs) 14:19, 23 November 2013 (UTC)

Testicular Cancer[edit]

Testicular Cancer

"In March 2015, a study published by the British Journal of Cancer found that men using supplements containing creatine may have a higher risk of getting testicular cancer [40][41]"

The link to the literature doesn't even mention creatine, all it says is they were on muscle building supplements and the link to webMD says "It’s also unknown what ingredients in muscle-building supplements might be responsible". I want permission to delete the above claim from the page.

And what is the half life of creatine in muscle and brain?


Meel11223 (talk) 11:04, 8 December 2015 (UTC)

 Done This information was not well-sourced, and so I have removed it. I will see if there is any better sourcing for this aspect of the topic. (Add: there doesn't appear to be anything that passes WP:MEDRS; one study suggested a link, but this has not been validated/covered by good secondary sources.) Alexbrn (talk) 11:07, 8 December 2015 (UTC)

There is absolutely no issues with the information reported. Editors should not decide whether the content of a study is validated or not but rather to add information if the topic has been extensively covered by reliable sources which this topic has. If you feel that the content has not been covered by reliable sources then we can follow the steps as listed at Wikipedia:Dispute resolution but please do not simply delete my addition without going through the process. If you feel the addition is not neutral we can change the wording so that it sounds more neutral. Addition mentions a study that has been covered extensively. if you want more sources I am also happy to add more sources Totocol (talk) 10:26, 23 December 2015 (UTC)

What you say is not in line with our WP:PAGs. Please see WP:MEDRS. Biomedical information should only be included if there are strong secondary sources for it, particularly for a major claim such as this. I looked for secondary sources on this topic but so far as I can see there are none. Alexbrn (talk) 14:45, 23 December 2015 (UTC)
I recommend you to review your understanding of secondary sources - there are absolutely no issues with the sources cited. They are reviews of what has been said in a reputable journal. If you have an issue with what has been said you can always add a counter view based on reputable secondary sources. I'm happy to include a third party opinion but please do not just start and edit war without having an actual reason. Totocol (talk) 18:58, 23 December 2015 (UTC)
Please read WP:MEDRS. The journal articles you use are primary sources, news pieces, and WebMD is not a great source. I shall raise a query at Wt:MED. Alexbrn (talk) 19:46, 23 December 2015 (UTC)
Alexbrn is correct, MEDRS[1] should always be followed, thank you--Ozzie10aaaa (talk) 20:38, 23 December 2015 (UTC)
one of the references is a primary source, al of the others are reliable secondary sources. Why has the whole cancer section been removed? Totocol (talk) 00:56, 24 December 2015 (UTC)
No, none of them was a peer-reviewed secondary source that complies with our relevant guideline. — soupvector (talk) 01:46, 24 December 2015 (UTC)
  • I don't think this study belongs on this page. The cited reference mentions "creatine" exactly twice:
  1. (in "Data Collection") The interview included an assessment of 30 different types of MBS powders or pills. The major ingredients, including creatine, protein, and androstenedione or its booster, were abstracted according to the product ingredients.
  2. (the last sentence of the Results) We further conducted exploratory stratified analyses examining associations with TGCC for the major types of MBS use reported by the study population and found that the use of MBS containing ingredients of both creatine and proteins increased the risk of TGCC significantly...
Since creatine was not singled out as a risk factor, and was not mentioned in the title or abstract of the paper, this seems WP:UNDUE and perhaps WP:SYNTH. — soupvector (talk) 20:46, 23 December 2015 (UTC)
  • Eventually there will be a review. The text was "A 2015 British Journal of Cancer study found that men using supplements containing creatine or androstenedione may have a higher risk of getting testicular cancer."[2] Li, N; Hauser, R; Holford, T; Zhu, Y; Zhang, Y; Bassig, B A; Honig, S; Chen, C; Boyle, P; Dai, M; Schwartz, S M; Morey, P; Sayward, H; Hu, Z; Shen, H; Gomery, P; Zheng, T (2015). "Muscle-building supplement use and increased risk of testicular germ cell cancer in men from Connecticut and Massachusetts". British Journal of Cancer. 112 (7): 1247–1250. doi:10.1038/bjc.2015.26. ISSN 0007-0920. PMID 25826226. QuackGuru (talk) 22:40, 23 December 2015 (UTC)
Or, eventually this will be refuted. Let's wait and see. — soupvector (talk) 01:45, 24 December 2015 (UTC)
Isn't the work of Wikipedia to summarise what's on reliable secondary sources rather than deciding whether you agree or not with the content? There are numerous reliable secondary sources that cite a study including Harvard School of Public Health and Brown University. 123.51.53.220 (talk) 04:38, 24 December 2015 (UTC)
Such as? Please indicate the best secondary source you found (I found none suitable so am curious). Alexbrn (talk) 04:42, 24 December 2015 (UTC)
Such as [1] and [2] and the list goes on. I am just curious why do you think they are not reliable secondary sources. Totocol (talk) 04:52, 24 December 2015 (UTC)

References

───────────────────────── These press-release-based news pieces are not WP:MEDRS for stating or implying biomedical knowledge. They are also not secondary sources for the cancer statement as they provide no interpretation, analysis, or evaluation of the research (just said it happened). We need review articles etc. Please read WP:MEDRS (and maybe WP:WHYMEDRS for background). For all we know this research is rubbish. Alexbrn (talk) 05:02, 24 December 2015 (UTC)

Agreed. In particular, the cited pieces are not peer-reviewed. — soupvector (talk) 05:23, 24 December 2015 (UTC)
The British Journal of Cancer is a reputable peer reviewed journal. Rather than deleting the content shouldn't you be trying to enrich the content by adding more information that you feel would show varied angles as described at WP:MEDRS 49.195.129.118 (talk) 07:11, 24 December 2015 (UTC)
No, because there is no reliable information on this. Alexbrn (talk) 07:13, 24 December 2015 (UTC)
  • A reliable source for such a claim would be a peer-reviewed, secondary source - but none has been brought forward. The Br J Cancer paper is the primary source (that paper presented the analysis); the commentaries are secondary but not peer reviewed. — soupvector (talk) 07:23, 24 December 2015 (UTC)

Only because no one else brought it up, a Letter to Editor, a few months later, same journal [Cazorla-Saravia P, Pereyra-Elías R. Is it the creatine or the anabolic androgenic steroids? Need for assessing the steroids role in testicular cancer. Br J Cancer. 2015 Dec 1;113(11):1638. doi: 10.1038/bjc.2015.294. PMID 26263480.] raised two valid theories for the connection - men using muscle building supplements (creatine, etc.) are often also users of anabolic steroids, and muscle building supplements may be 'spiked' with undisclosed anabolic steroids.David notMD (talk) 05:52, 1 March 2017 (UTC)

ISSN journal[edit]

@ScienceandFitness: you noted that the International Society of Sports Nutrition is known to have engaged in p-hacking in your recent edit summary when you removed an external link to one of their systematic reviews (or "position stands" as they call them); can you provide a link to a reliable source that supports this assertion? Seppi333 (Insert ) 21:28, 12 October 2016 (UTC)

@Seppi333: All via FB, even in their group. Most telling was a study a year or two ago which claimed creatine-timing mattered, but looking at the dataset itself made it quite obvious that they were wringing the statistics to make it work. Subsequent studies all showed that timing of creatine did not matter.

horribly written[edit]

The first part is written in a confusing, and non direct way not to mention being wrong in some places

Creatine (/ˈkriːətiːn/ or /ˈkriːətɪn/[1][2]) is a nitrogenous organic acid that occurs naturally in vertebrates and helps to supply energy to all cells (well not all cells mainly muscle, and to a lesser extent brain, and some other organs) in the body, primarily muscle. This is achieved by increasing the formation of adenosine triphosphate (ATP). Early analysis showed that human blood is approximately 1% creatine, and the highest concentrations are found in animal blood (LOL first it says human blood, and then changes to animal blood???), brain (0.14%) (listing a lower source of it first?), muscle (0.50%) (the major location of creatine, and should be listed first and it is actually 95%), and testes (0.18%). The liver and kidney contain approximately 0.01% creatine.

How about

Creatine (/ˈkriːətiːn/ or /ˈkriːətɪn/[1][2]) is a nitrogenous organic acid that occurs naturally in vertebrates. It's role is to recycle ATP, the energy currency of the cell, primarily in muscle but also in the brain. This is achieved by recycling ADP to ATP via donation of phosphate groups.

Creatine is produced endogenously at an amount of about 1 g/d. Synthesis predominately occurs in the liver, kidneys, and to a lesser extent in the pancreas. The remainder of the creatine available to the body is obtained through the diet at about 1 g/d for an omnivorous diet. 95% of the bodies creatine stores are found in the skeletal muscle and the remaining 5% is distributed in the brain, liver, kidney, and testes

I can see you have that down further in the article but it is more appropriate in the introduction.

I recommend a change immediately. The introduction is an abomination. Meel11223 (talk) 13:26, 21 January 2017 (UTC)

I've edited the lead based upon your proposed edits, but modified it for consistency with a couple reviews that I've cited. The 95% figure wasn't mentioned in the cited source in the body, so I've removed it. The endogenous production rate also wasn't supported by a source, so I used a recent review one to cite an amount of 8.3 mmol/day in young adults. Let me know if you think there are still any unresolved issues. Seppi333 (Insert ) 22:49, 21 January 2017 (UTC)
Edit: I just noticed the review you cited below supports the 95% figure, but the proposed addition here is the exact wording used in the source. I've added the review, but had to change the wording to avoid issues with WP:COPYVIO. Seppi333 (Insert ) 23:02, 21 January 2017 (UTC)

It looks good seppi333. A lot of questions about creatine are answered in the opening paragraph now. Kudos Meel11223 (talk) 08:15, 23 January 2017 (UTC)

Semi-protected edit request on 21 January 2017[edit]

Creatine (/ˈkriːətiːn/ or /ˈkriːətɪn/[1][2]) is a nitrogenous organic acid that occurs naturally in vertebrates. It's role is to recycle ATP, the energy currency of the cell, primarily in muscle but also to a lesser extent in the brain, and several other organs. This is achieved by donating phosphate groups to ADP to regenerate ATP.

Creatine is produced endogenously at an amount of about 1 g/d. Synthesis predominately occurs in the liver, kidneys, and to a lesser extent in the pancreas. The remainder of the creatine available to the body is obtained through the diet at about 1 g/d for an omnivorous diet. 95% of the bodies creatine stores are found in the skeletal muscle and the remaining 5% is distributed in the brain, liver, kidney, and testes

With this as the reference for the second paragraph https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3407788/ Meel11223 (talk) 13:53, 21 January 2017 (UTC)

See the above thread. Seppi333 (Insert ) 23:03, 21 January 2017 (UTC)

Questions About the Heterocyclic Amines Section[edit]

"Heterocyclic amines

When creatine is mixed with protein and sugar at high temperatures (above 148 °C), the resulting reaction produces heterocyclic amines (HCAs). Such a reaction happens when grilling or pan frying meat.[42] Creatine content (as a percentage of crude protein) can be used as an indicator of meat quality.[43]

A Meta-analysis from 2011 concluded that "search for the excretion of heterocyclic amines remains a future task to definitively exclude the unproved allegation made by some national agencies".[31]"

1) What are 'heterocyclic amines?

2) Are they good, bad, indifferent, and why? (I vaguely remember reading that 'amines' -- bad -- are produced when cooking out using charcoal, but that isn't what this section says.)

3) The first paragraph starts off explaining how heterocyclic amines are produced, then the third sentence of that paragraph is about something else, namely that the creatine content of meat can indicate the quality of that meat. Why is that useful information?

4) Second paragraph:

a) 'search for the excretion of'. . . meaning 'how heterocyclic amines are excreted from the body'

b) what 'unproved allegation'?

c) how will understanding the pathway of heterocyclic amine excretion definitively exclude that unproved allegation?

Langing (talk) 12:36, 19 October 2017 (UTC)

Creatine Synthesis incorrect pathway[edit]

Creatine is synthesized via a two step reaction with two different enzymes: 1. Arginine:Glycine Amindinotrasferase (AGAT - sometimes called GATM in older papers). 2. Guanidinoacetate methyltransferase (GAMT).

The current image incorrectly has GAMT catalyzing both steps. Step 1 should be labeled as AGAT.

Thanks for your great work. — Preceding unsigned comment added by 199.68.233.102 (talkcontribs) 14:00, 28 November 2017 (UTC)

The current image clearly shows GATM then GAMT - as you suggest it should. You suggest that AGAT is the new name for GATM, but it appears that GATM remains current. It's true that the article is inconsistent in use of AGAT and GATM - is that what you're concerned about, or am I missing something else that you're seeing? — soupvector (talk) 02:56, 1 December 2017 (UTC)

Contraindications[edit]

The "supplement" section currently begins with: "The Mayo Clinic states that creatine has been associated with asthmatic symptoms and warns against consumption by persons with known allergies to creatine.[17]". The citation is a 404, and the statement that "[literally anybody] warns against consumption by persons with known allergies to creatine" is too obvious to mention, so I will edit this portion out whilst leaving the start of the sentence with a "citation needed" tag. I (and many other weightlifters, I'm sure) would welcome somebody more knowledgeable to advise us of any properly sourced contraindications.2A00:23C4:4F07:1000:51ED:B111:9877:ABB1 (talk) 21:30, 4 January 2018 (UTC)

Mayo is not MEDRS; that is gone. Jytdog (talk) 14:11, 8 May 2018 (UTC)

Note - merging back[edit]

I merged Creatine supplement back to here. It had been split out way back in 2007. In the ensuing 11 years this article blew up to recreate the supplement content here, and the articles developed independently, saying different, partial, and inconsistent things. They also each became shot through with bad content including blatant spam.

I left a similar message on the supplement talk page.

If folks want to discuss a resplit now that we have a unified chunk of content (which still needs a bunch of work) that is fine, but we would have to be careful not to let that happen again. Jytdog (talk) 14:11, 8 May 2018 (UTC)

Additions to Supplement health effects[edit]

Hello Jytdog, I have been reviewing the literature on the health effects of creatine supplements and would like to add some additions. Some references are meta-analyses, and others are individual studies. I apologize if I added to the clutter already present - I see you removed a lot of content that was previously added and also some content I added recently. See my sandbox for the types of additions I would like to make. I would love to hear your feedback. I am a new Wikipedia user, so please be patient with me!

BetaEdits (talk) 04:25, 5 May 2018 (UTC)

Content based on individual studies will not be OK. Please use sources that are OK per WP:MEDRS. Please be sure you have read WP:MEDMOS too (no references to "patient", etc). Let me know when it is ready! Jytdog (talk) 20:35, 8 May 2018 (UTC)