Talk:Caffeine/Archive 1

The Image
Pardon me for not keeping track, but what was the decision on images in wikipedia for things like molecule structures? I've just sent Larry a .png I created of the caffeine molecule, b/c the transcription on the main page looks so foreign to what I'm used to seeing--but I'm not a chemist, nor did I progress beyond CHM 2400. :-) Should we create our own images, or handle it through ASCII art?  The advantage of images would be that some vandal can't come in and change, say, an "H" to a "C" and slip it through.  The disadvantage is that some professor can't come in and change, say, an "H" to a "C" and have it be duly noticed. Also, the images won't display in text browsers.  Opinions?  --KQ

Without images, the web wouldn't be what it is; I say, go for the images. - Yay! that's the quickest turnaround on any request for a new entry that *I've* ever made! MichaelTinkler, caffeine-addict

That's because you're not the only caffeine addict here. :) -- Taw (who started Caffeine entry and is proud of it).

KQ, a professor could still come in and make a note that the depiction isn't right, and someone could just then go fix it and repost it. Right?

That's true I guess. The .png doesn't show up in IE 5.0 tho (or Opera 5.01), for some reason. It works in Photoshop, Irfanview, and NS 6.1. Any suggestions? Lee? Optimum format, preferences to toggle, etc.? --Koyaanis Qatsi

What PNG? IE 5.0 should be fine (See, for example, http://www.libpng.org/pub/png/pngsuite.html to verify your browser). If you can give me a URL for the actual file you're talking about, I'll see if it is a correctly coded image file. --LDC

The reason it doesn't show might be that there's no link in the article... --Magnus Manske

Since I can't work out (from the discusion above) whether anybody has actually made an image, I went ahead and made one for my favourite molecule. BTW I'm not really a chemist so I used the ASCII structure as a reference, somebody else should check it. -- DrBob

Anyhow, the Image works fine on Firefox. Now, if it were possible to have a graphics/ASCII images option... Erre 01:57, 9 Mar 2005 (UTC)

Leaving out carbons
I am a synthetic organic chemist and do not see where any carbon atoms have been omited unless one is speaking about not putting the letter C at the junctures of lines. It is standard notation not to do that. Indeed it would also be just as appropriate just to put small, plain straight lines for the methly groups (-CH3).

If one did leave out carbon atoms then that would not be correct. Example, what would methamphetamine be if you left out a carbon atom?

What are left out are hydrogen atoms and they should be, since it has been previously pointed out, they would unduly clutter the diagram and are unnecessary as being implied anyway.

---

I have made an image, which I emailed to Larry, but I did something wrong and it doesn't work in IE 5.0. I'll send it to LDC so he can point out what I've done wrong, but right now I'm at work and the image is at home. Thanks for making an image of your own, but the diagram leaves out the individual carbon atoms, and also has a shape different from how it's usually drawn, because it's based on the ASCII art, which is limited to pipes and slashes to indicate bonds. I'll send the image to LDC tonight when I get home. --Koyaanis Qatsi

--> I AM a chem major, and yes, you traditionally leave out the carbons, occasionally on carbbohydrate chemistry an older notation is used where hydrogens are also omitted, biochemists use yet another notation, it's really quite confusing, but technically speaking, the chemical model is correct w/o the carbons, the methyl carbons however, are debatable

--- It was my impression that in schematic diagrams like this is was traditional to leave out the carbon atoms rather than clutter the diagram with what is otherwise obvious. Of course a more pictorial representation (such as a ray-traced picture with spherical atoms) has to leave them in. --LDC

Well, it's been a long time since CHM, but the only atoms I remember leaving out were the hydrogen ones. Is it customary to leave out the carbons, too? Anyone? --KQ

Well, I thought it was, which is why I left them out in the first place. I've certainly seen diagrams printed that way. But as I say, I'm not a chemist. -- DrBob - I'm seeing it half and half on a google image search. Maybe a chemist can come explain to us laypeople. :-) --KQ

There are lots of carbons in lots of compounds. We leave them out as often as possible -BUT we know what we are talking about. That may not hold for a general audience. -A chemist.

As a to-be-biochemist, it looks good to me. Definitely sufficient. --Magnus Manske

I'm not a chemist, or looking to be one, and it definitely wouldn't have been clear to me. Who is your audience, anyway?
 * We can't teach all of chemistry in the caffeine article, don't you agree? Those who know what the image means (at least roughly;) will welcome it, and the others should take a chemistry class! The image is additional, it is not the central part of the article. But, if you (whoever you are) would like to start a "how to learn chemistry" wiki, go ahead, I will contribute when I have some time :) --Magnus Manske

I'm not sure I agree. I know what the image means, but I wouldn't have guessed that there were Carbons at the intersection of each 4 bonds without a letter there--though, with the C listed, I could tell you that the C stood for Carbon. Is it a stylistic matter (some of the images do show the C)? --KQ

In chemistry texts, carbon atoms in rings are left out more often than not, especially aromatic rings like benzene but other rings as well, and occasionally in straight chains. The only real exceptions are when you want to point out optical activity and when you want to make it really, really plain what is happening. I think it would be better to explain the convention somewhere than to try and put carbons in everywhere - consider what will happen with chlorophyll and heme.

For a practical example when to draw carbons, see for aspirin drawn with and without carbon atoms. I think the initial remark was about "images of Lewis structures are too complicated for the unwashed masses", though. Or am I mistaken? --Magnus Manske - That ring (the benzene ring) is, as they say, so common that it is usually drawn like that, but if you'll notice, the Carbons are still indicated in the attached molecule. --KQ

That's because the attachment is a straight chain, corresponding to the CH3 groups here, where carbon are shown. It is fairly rare, though not unheard of in larger molecules, for carbons to be omitted in straight chains, since it isn't quite as clear how to replace them.

I work in the united states and I have never seen a carbon atom written in. I think that carbons should be unmarked to follow the precedent set by traditional publications. As for the masses reading the article, if they don't have a foundation that would enable them to understand the structure drawing system, the picture would probably be useless to them anyways.

Here's the image KQ sent; I don't have any particular preference, but someone might.

http://www.piclab.com/images/caf.png

3D picture

 * 1) Could the person who posted the 3D caffeine picture please shrink and crop it -- it's larger than my monitor!
 * 2) Also, if you didn't use freeware to produce the caffeine model, you probably need to mention the name of the software (I know you do, if it's from Insight II, since I used to work at Accelrys when it was MSI). -- Marj Tiefert, Tuesday, April 2, 2002


 * I'll even do some of the work for you--I'll crop it and shrink, it when I get home tonight. But it still probably ought to be attributed.  --LDC

I temporarily removed said picture (uploaded by Little_guru) from the article. For the curious, here it is again:


 * Why don't you use the public domain federally funded picture that you can find using "chemid" at http://chem.sis.nlm.nih.gov/chemidplus/chemidlite.jsp

I think a 3d picture of caffeine (and indeed of all important molecules, especially water) are very desirable. They can be made easily with the free software RasMol: http://www.umass.edu/microbio/rasmol/ In order to render a molecule, you need a coordinate file; these are also widely available for free on many sites. AxelBoldt

types of structure representation
This is an important dicussion - it applies to a lot of molecular structures. The following are all useful methods for describing compounds:
 * a registry number (there are many of these and they have no semantics)
 * the molecular connection table (which atoms are connected to which). This is often a structured file but there are two common inline formats, SMILES and InChI. The latter is becoming very widely used and we recommend it for all Wikipedia chemistry where possible
 * a 2D diagram. There is considerable flexibility in how this is drawn - are hydrogens to be included? Carbons? Should the molecule have a standard orientation? (For example I normally draw caffeine flipped about a vertical axis from the current picture and I suspect most people would, but it's not wrong.) The 2D diagram can usually be generated by machine from the connection table but it won't always be as aesthetic as the human ones but it will always be correct!
 * 3D coordinates. These are obtained experimentally (e.g. by X-ray diffraction, by computation, or by model building. For some molecules (such as caffeine) there is only one possibility (apart from rotations about the N-CH3 bonds) but for many other molecules there are many conformations. 3D diagrams are great fun and if you can get the Jmol software running in some way (http://www.jmol.org) readers will love it.

(Peter Murray-Rust, http://wwmm.ch.cam.ac.uk)


 * You could, of course, become a Wikipedia editor and assist in this noble plan. It hope it was not you who left some grafitti on the page 16 minutes prior to your above message. JFW | T@lk  12:25, 5 December 2005 (UTC)

Greetings and thanks. I am very committed to the Wikipedia approach - it is mainly a question of time. One major project is to add InChIs to everything.

I am afraid it was me who added the graffiti! I thought that it was allowed to do this to demonstrate cleanup. But I won't do it again.

Best

P.

Removed

 * The cytochrome P450 system, which is responsible for breaking down caffeine, is not fully matured until about the age of 7 to 9 months (after birth). Indeed, the chemical half-life of caffeine in the infant's metabolism has been determined to be up to 120 hours, as opposed to the typical 3.5 to 10 hours in older children and adults. This means that continued exposition of unborn children and neonates to caffeine (e.g. through the placenta during pregnancy or through breast milk after birth) could lead to an accumulation of caffeine to toxic concentrations even at a moderate caffeine intake by the mother.

This is pharmacokinetic nonsense. Even if there were no foetal metabolism, the caffeine level would not rise above the level in the maternal blood. As the mother metabolises caffeine, the foetal caffeine would diffuse back across the placenta. bignoter

Toxicity
Tuxisuau - toxicity is measured using a measurement called LD50 (Lethal dose for 50% of a population), and so the use of the term half the population is actually correct. I am going to change back for now, but please feel free to add info to the discussion. Thanks Ddroar

Ddroar - Ok, then u're right. But if u know about LD50, it will be better to add some reference to it (as u can see, i had no idea, so I invite u to write it) (Tuxisuau)

With all due respect, an LD50 for caffeine of 10g / kg of body mass seems ridiculous. That would mean that 1/100th of your body mass would have to be caffeine to have a 50% chance of killing you! Several other sites I found seem to give values more like 75-150mg / kg of body mass, which seem much more reasonable. I don't have an authoritative source, but someone who does should look this up and put in the right value.
 * This site lists some values for mice and rats. Seems to be in the 50-300 mg/kg range, not sure if it's the same for humans, but 10g/kg seems way too high and these numbers are probably closer.
 * Toxicological Data: Oral rat LD50: 192 mg/kg. Investigated as a tumorigen, mutagen, reproductive effector. Reproductive Toxicity: May cause teratogenic effects. (doesn't mean I'd ever stop drinking espresso)

Yerba Mate
Ok, I just looked up "mateine" in response to the claim that yerba mate doesn't have caffeine, but a similar chemical compound called "mateine." I found 132 results in google, most of them in fringe or alternative publications. I'd feel much better about it if we had some backing from a recognized authority, such as a peer-reviewed scientific journal. Koyaanis Qatsi, Monday, April 1, 2002

it does not have it... i just checked all the 4 diff. types of mate packages i found at home now; they have all the other things like potassium content specified; no caffeine... as far as you won't find the mate in your supermarket i suppose you wont find the non-recognised articles either. try some of these: http://www.lasmarias.com.ar/ilayerba_nut.htm http://www.yerbamate.co.uk/pages/page10.htm Zisa

I will find mate in my supermarket, and my package (Yogi Green tea mate) says it contains 44mg caffeine per cup. The Yogie mint mate says "7.5 mg" per cup, so I'm guessing that mate itself has at least 7.5 mg caffeine, as it's commonly understood. Thanks for the links though. Koyaanis Qatsi, Monday, April 1, 2002

okay... the mates i have found here i have bought in uk, italy and argentina and in none of these packets i have found any mgs or mentions of caffeine, instead e.x. taragui mate has specified its kcals, proteines, lipides, glucidos, fibers, pantonine acids, riboflavine, potasium, magnesium and other minerals. Zisa btw, 'green tea mate' is partly green tea and partly yerba or pure mate?

Partly green tea and partly mate. But the green tea mate' (w/ 7.5mg caffeine [or mateine]) has no other caffeine-containing ingredient. I think LDC, below, is on to somethine when he suggests we let scientists come to a conclusion on it, then just report what they determine. cheers, Koyaanis Qatsi

I changed the Yerba Mate page; for this page, though, I think it's fine to just leave out any mention of mate. It's not really critical to describing caffeine as such, and it avoids having to change the article when later research finally decides the question. -- Lee Daniel Crocker

That sounds like a good approach. Koyaanis Qatsi

I have taken a somewhat less drastic approach in this spirit (removing claims I can't substantiate, but leaving reference to mate). btw the non-mention of caffeine on the packaging doesn't mean anything; tea and coffee aren't required to mention it either (at least in Canada and the US), since they're not products to which it's been added as a food ingredient. toh

I have taken a more direct approach regarding mateine - all the claims that mateine is not caffeine are based on bunk science. Avoiding mentioning it now to avoid having to change the article later presumes that later research will prove mateine is not caffeine. Starting with that assumption, if mateine *is* caffeine, what is sufficient 'later research' to let the result be mentioned? Better to stick with current knowledge for now, and let later results deal with themselves. I understand that many people have different experiences with yerba mat&eacute; than with coffee, but that doesn't mean that it's a lack of caffeine. There are plenty of other chemicals in coffee and yerba mat&eacute;, any of which could significantly change how it interacts with our bodies. --Matthew Weigel

How does it work?
How and why does caffeine stimulate the nervous system? AxelBoldt

Content chart controversy
I think the caffeine content numbers will mislead a lot of lazy readers and will help others a lot less than they easily could. For readers to correctly compare the different caffeine sources, they need to know the content per serving, not content per arbitrary unit. So for regular coffee I think we should state the content "mg per 8-ounce cup" ( or really to use consistent units I think it should be "mg per 250 mL serving" ). Espresso is more potent, but a shot is only 50mL, so the caffeine content should be stated in "mg per 50 mL shot." Incidentally, even for readers who are inclined to calculate serving content themselves, some of the numbers are perfectly useless, because "ounce" could mean either weight or volume in the context of cofee, and "coffee" could mean either liquid or beans in the context of the unqualified word, "ounce." 168... 17:55, 21 Oct 2003 (UTC)

The listed caffeine content for yerba maté is absurd in this table; if it were 200mg/oz then I doubt I'd be able to feel my face as I write this. Maté's caffeine content is similar to black or oolong tea (relatively high in terms of mg/g of dried leaf, but lower than coffee in the beverage as variously prepared). Perhaps the writer confused the dry content with that of the beverage, or perhaps it's just that "more mate marketing misinformation means major money".

I am removing mate from the table until a verifiable figure can be found.

- toh

Another possible link
Would a link to http://www.erowid.org/chemicals/caffeine/caffeine.shtml be appropriate?

Copyright issue
Much of the Metabolism & Toxicology section seems to be taken from http://www.drowning.com/caffeine.html. Isn't that a copyright violation?


 * It probably is, unless both are copied from a US government (FDA, CDC, whatever) work. Pakaran. 14:06, 14 Oct 2004 (UTC)


 * It is from the DSM IV, which is copyright (but possibly fair use) the American Psychiatric Association. JFW | T@lk  14:48, 14 Oct 2004 (UTC)


 * The APA is very protective of its copyright. We could probably get away with quoting small parts of it, but if each of our articles on a subject in the DSM quotes from the relevant section, that could quickly add up to a problematic amount of total quoting. --Delirium 08:49, Nov 20, 2004 (UTC)

Should we really be copy and pasting unattributed paragraphs from one of the bottom links? (See the whole thing about 'caffeine intoxication')

Shirt
Do you wikipedians mind if I include a link to the Caffeine Shirt (http://www.thinkgeek.com/tshirts/generic/2891/) and the Caffeine Keychain (http://www.thinkgeek.com/gadgets/lights/6a43/) in the External Links part?


 * I don't see how those products give any further encyclopedic information on Caffeine, so I'd advise against it. - Mpnolan 04:07, 21 Dec 2004 (UTC)

Caffeine and chocolate
Are we sure we're not confusing chocolate's caffeine content with its theobromine content? Theobromine is the primary stimulant, and its caffeine content is much less. - Gilgamesh 23:29, 26 Oct 2004 (UTC)

"The Biochemist, (Apr/May 1993, p 15) did chemical composition tests where they specifically distinguished between Caffeine and Theobromine. They found regularly up to 1.3% by weight Theobromine in Chocolate. They also found other pharmacologically active compounds including up to 2.20% Phenylethylamine up to 1.54% Tele- methylhistamine and occasionally up to 5.82% Serotonin. They could not detect any Caffeine at all."

and many more pages tell this inevitable truth. No caffeine in chocolate unless added afterwards. Maybe you ought to correct this like has been done for the foreign versions of this page?


 * Maybe some day someone will explain the difference between "could not detect" and "does not contain" to you. Until then, I hope you will enjoy this link. No one disputes that theobromine and tryptophan (I'm not sure whether cocoa contains actual serotonine) are more important constituents of cocoa than caffeine. BTW, the page you have cited also repeats the "Yerba Maté has no caffeine" myth claiming that "mateine" was a stereoisomer of caffeine (see the article for details why this is bunk). Aragorn2 18:49, 18 December 2005 (UTC)

If you cite a valid ref. here saying chocolate DOES contain caffeine, maybe you should give that on the real page, not this bs. There is nothing in the above ref. that says chocolate contains caffeine. Instead they mention that caffeine was given as part of the treatment, in addition to chocolate. Seriously, get with it.

Caffeine content of Green Tea, etc.
Doesn't the caffeine content of green tea vary wildly with the type of green tea in question (e.g., sencha vs. gyokuro-cha)? Why aren't any sources being credited for these data?

Anecdote about coffee plant with little caffeine
Assuming that the information is accurate, the data I removed (compare my revision to 08:05, 15 Feb 2005) about a coffee plant in Ethiopia which contains very little caffeine should be moved to the coffee and/or coffee plant article (if such an article exists, as it should).

The passage is useful information, but requires significant rework to the writing style. I'm unsure of its accuracy.

Source of caffeine in soft drinks?
Is the caffeine added to fizzy drinks chemically synthesized? Extracted from vegetable sources (guarana? coffee? what?)?
 * It's 'waste' from coffee decaffeination. Cacycle 23:01, 15 Mar 2005 (UTC)

Units
If anyone's got time, the section on concentrations could do with editing so that the SI are the primary units, with other units in parentheses.

I second that - having a mix of different non-SI units makes it hard to compare the caffeine doses -- anon

Toxicity

 * Too much caffeine can lead to caffeine intoxication. The symptoms of this disorder are restlessness, nervousness, excitement, insomnia, flushed face, diuresis, gastrointestinal complaints, even hallucinations. They can occur in some people after as little as 250 mg per day.

I'm very sceptical to the claim that 250 mg can cause hallucinations in anyone. Is there any source for it ?
 * Considering that an *average* Finn consumes 400-500 mg of caffeine per day (from ~0.5l of coffee) I find that claim ludicrous.

As for the other claims, calling those symptoms "caffeine intoxication" doesn't seem appropriate. They're mostly organism's natural reaction to stress, and the caffeine is supposed to induce them, in intensity depending on dosage. The article could be a little more balanced. Taw 01:22, 24 May 2005 (UTC)

-- It should be considered that caffeine tollerance develops very quickly. 250mg given to a small person with no caffeine tollerance could cause very drastic effects. I've seen people given as little as 300mg become wrecks, because they have no tolerance, while I have used 1200mg or more in the course of a day without apparent ill effect. I would LOVE to see some mathematical formulae that represent the PERCIEVED dose of caffeine, given adaptation to exposure. I would imagine that hallucinations are a result of VERY high doeses possibly combined with sensitivity to caffeine. In my experience, nervousness, irritability, lack of coordination, and gastointestinal complaints are most common. Again, all of this is annecdotal, but does provide some reference to the 250mg figure.


 * haha...Pull the other one. 250 mg can't under any *normal* circumstance induce hallucinations unless you're suffering from extreme oversensitivity and extremely low BMI. That's 3 cups of coffee for chrissakes - Sure I've seen people with little to no normal caffeine intake drink energy drinks, coffee or consume caffeine pills and the only symptoms I've witnessed are slight overanxiety, sweating along with what you called gastrointestinal complaints aka gas. I find this article with its links extremely biased...I'd dispute its neutrality if I only knew how :P

Depression
No mention of caffeine's links with depressive illness.
 * Because this isn't a pseudoscience wiki. -- Zantastik talk  08:05, 15 Jun 2005 (UTC)


 * Another great and dismissive Wikipedian reply. There exists mountain of evidence linking heavy caffeine consumption with depression. A 2 second google search would have shown you that. Rotten


 * If you're referring to the potential for caffeine to cause adverse effects, like insomnia, it's covered towards the end of the article. Otherwise, I agree with Zantastik. (pops open a mountain dew, sings a happy song) - Jersyko  talk  12:30, Jun 15, 2005 (UTC)


 * Caffeine is the root of all evil, didn't you know? JFW | T@lk  06:37, 25 July 2005 (UTC)

I'm not sure caffeine causing depression qualifies as "pseudoscience." If i drink excessive amounts of caffeine, after the crash I tend to get pretty depressed. iamtexture

Inaccuracies with Caffeine in Tea
"This article states that green tea has less caffeine than does black tea, while black tea is nothing but green tea that has been subjected to a process of oxidization. If someone disagrees, then tell me why I'm wrong and reinsert the material that I'm about to remove."

Reply to Zantastik: The fermenting process (withering, rolling, allowing oxidation) results in the leaves turning darker and more of the juices created by the process ending up on the outside of the leaves. Then, the leaves are blasted. So, black tea, which is fermented, DOES result in higher caffeine levels than green & white tea, which are unfermented. I think what leads to the higher levels is more of the juices dried onto the outside of the leaves.

-- Zantastik talk  08:03, 15 Jun 2005 (UTC)

Caffeine as an appetite suppressant?
This is a somewhat uninformed question - but I notice that whenever I drink coffee in the morning (9,10am) I'm not hungry again until dinner time. I have a constant feeling of fullness, yet I know caffeine speeds up one's metabolism. Is this an effect of caffeine, the particular coffee, or maybe the cream perhaps (I don't use sugar)?

Also, what causes "the shakes"? Is it just the musculo-nervous system over-wired from the caffeine, or something else? Are the shakes from caffeine the same shakes from low blood sugar?

-> Yeah, I think this point deserves to be in the wiki. Many (most?) diet pills contain substantial caffeine as an appetite suppressant so I would include it. I get the same effect, when I don't drink coffee I eat more... obviously in the long term it's unlikely to keep off more than 2 or 3 pounds, or we'd all know about it and it would be constantly talked about.

Solubility/ boiling and melting points
Anyone know if caffeine is soluble in ethanol or other solvent and if so how soluble it is? The other thing is, I answered about the subliming buisness above, but under what conditions does caffeine melt instead of sublime? I'm assuming it has something to do with pressure, in which case this pressure should be indicated in the article. --2tothe4 23:25, 27 October 2005 (UTC)
 * As a general rule, the more the volume changes during a reaction, the more that reaction is affected by pressure (see Phase diagram). So bp is expected to be highly pressure-dependent while melting is reasonably independent of pressure. If P is not known, a reported bp value is pretty useless. However, there are standards that may be implied. DMacks 09:07, 15 February 2006 (UTC)

I actually found part of it... I found it's insoluble in ethanol(on the godawful slow online CRC, at http://www.hbcpnetbase.com/ ) But no luck on the melting conditions yet. --2tothe4 23:42, 27 October 2005 (UTC)

History section needs improvement
I believe "the first documented use of caffeine in a beverage for its pharmacological effect" was by Buddhist monks, of the sect best known as Zen (Chan in Mandarin Chinese; Son/Seon in Korean). Zen made it to Japan in the 12th century, meaning it was in Korea and China even earlier. However, I don't know the dates for the history of green tea use within Zen Buddhism. Anybody else know? Squidley 07:29, 17 November 2005 (UTC)

"4 to 20 mg/floz ... (40 to 170 mg/5 floz)"
Inconsistent arithmetic. Please check for correct figures. Jclerman 04:29, 22 November 2005 (UTC)

Caffeine extraction
About solubility, I'm a college student and I did a lab consisting of the extraction of caffeine from Red Bull. I have my entire protocol I could summarise for this page to point out that though it isn't difficult, it requires some time and a good amount of equipement for it to be done. I posted a sumamry about the extraction on the french page, go see it and tell me if it makes sense (it should, because I did that in my lab and it worked).

We used chloroform to get the caffeine out of the drink so it should be a nice organic solvant, though to what extent...

I was thinking something along these lines:

"It is very difficult to know the exact amount of caffeine in a particular drink that is not automatically prepared. The ammount of caffeine in a single serving of coffee varies considerably due to many variables. Concentration can vary from bean to bean within a given bush; prepration of the raw bean will affect concentration, as well as multiple variables involved in brewing.

To extract caffeine takes some time (about two hours) and requires chemicals unavailable for everyday use and a nice system of distillation and sublimation. To extract caffeine, one must take the beverage one wants to extract the caffeine from and mix it with a solvent with a finer affiliation to the caffeine and a different density. Chloroform is known to possess both these properties.

Caffeine will go in the solvent it is the most soluble in, and it is more soluble in chloroform than water. Using a separating funnel, one should take about 30 ml of chloroform and 200 ml of the beverage one wants to extract the caffeine from and agitate for about two minutes. The bottom phase will be the chloroform and the caffeine, so one will keep this phase. Repeating this step about five times should ensure extraction of most of the caffeine.

The next step is a distillation using a standard distillation column where one gets rid of most of the chloroform. Finally, one has to sublimate the caffeine under vacuum."

Does that fit with the objective of this article? The PA 01:47, 8 December 2005 (UTC)


 * Comment I think that's a great nugget of info to include in the article. It's well-written and I can only think of a few suggestions. You might consider reducing the use of "you" (there's a grammatical word for this that I can't immediately recall) in favor of "one" or some other workaround. Change "The amount of caffeine in, say, a cup of coffee, varies a lot, even if it is made by the same person the same way every day" to something like "The ammount of caffiene in a single serving of coffee varies considerably due to many variables.  Concentration can vary from bean to bean within a given bush; prepration of the raw bean will affect concentration, as well as multiple variables involved in brewing." My version isn't that great; I'm just suggesting a more encyclopedia-like and less conversational voice. Jasmol 03:31, 8 December 2005 (UTC)
 * It's nice, I like it! I'll edit my above post to your ideas and wait around just a couple days more to decide where to put it and wait for more feedback. The PA 04:30, 8 December 2005 (UTC)
 * I'll put it in the article and see what happens, as it's not getting a lot of attention this way. The PA 01:16, 12 December 2005 (UTC)

Long term effects
It would be nice if there was more on the long term effect of regular caffiene use in this article.
 * Well there is the part about caffeine addiction on the article which I find interesting and concerns this subject. The PA 05:25, 29 December 2005 (UTC)

Major rewrite/reformat
I was very bold, and went ahead and spent four hours reformatting this entire article. Overall, very little was removed (except a bit on caffeine chirality that I thought was too technical), but a great deal of reorganization and copyediting took place. One major flaw of this article was one that most major articles can claim after a period of time: an accumlation of minor one-line edits that contribute to an overall awkwardness to the article. I hope that I haven't offended anybody with my changes, but please keep in mind that I put a vast amount of thought and effort into it. Ironically, I didn't enjoy any caffeine at all while I did this work. – ClockworkSoul 02:07, 31 December 2005 (UTC)

Semi-protected edit request on 23 February 2019
Amirhussain30001 (talk) 12:19, 23 February 2019 (UTC) Caffeine's potential health benefits.Improve Energy Levels and Make You Smarter. It can help people feel less tired and increase energy levels.]
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. DannyS712 (talk) 16:01, 23 February 2019 (UTC)

"Health effects of caffeine" redirect page
"Health effects of caffeine" currently redirects to a section that only describes adverse effects of caffeine, though the lead section describes "positive and negative" health effects. Should this redirect page be re-targeted to another section? Jarble (talk) 21:34, 25 February 2019 (UTC)

Grammatical error under sub-section "Dependence and withdrawal" of "Adverse effects".
The sentence immediately following "Mild physical dependence and withdrawal symptoms may occur upon abstinence, with greater than 100 mg caffeine per day, although these symptoms last no longer than a day." does not start with a capital letter. Originally Origins (talk) 14:03, 24 May 2019 (UTC)


 * Fixed. — Anita5192 (talk) 17:27, 24 May 2019 (UTC)

Typos
1, "A It appears that caffeine improves" - suppose the "A" is a typo. pls an editor with access see to it. thx.

2, "While this effect is not present during to exhaustion exercise" - suppose "to" is a typo, too.

3, "Products containing caffeine are coffee, tea, soft drinks ("colas"), energy drinks, other beverages, chocolate,[195] caffeine tablets, other oral products, and inhalation." - correct the end of the sentence to " other oral and inhalation products."89.134.199.32 (talk) 21:03, 7 June 2019 (UTC).


 * Fixed. — Anita5192 (talk) 21:36, 7 June 2019 (UTC)


 * highly appreciated:).

4, also there is a comparison of chocholate bars (milk and dark) coffeine content, which starts with "a typical serving of 28-grams milk chocholate bar" and then goes on on dark chocholates consistently using the "x mg coffeine per 100 gram of dark chocholate" formula, which seems to some extent incoherent. i personally would prefer the persistent use of comparable amounts =the x mg/100 g format), but this might be my personal taste.

5, "Tablets offer several advantages over coffee, tea, and other caffeinated beverages, including convenience, known dosage, and avoidance of concomitant intake of sugar, acids, and fluids." - it sounds like the article stands by the claim that these DIFFERENCES between the consumption of coffeine in tablet form and in beverage form are ADVANTAGES - which is highly debatable imho. better to use a more neutral wording, or just delete the whole sentence, because it is making a batch of statements that are either trivial, or fundamentally not proveable, eg: fluid intake is by no means a disadvantage for enhancing performance and is also not avoidably with tablets; sugar intake might be debated in some extreme cases as a disdvantage, but it is by no means mandatory to prepare your coffee/tea with sugar therefore the tablets would only be different from premixed beverages, like colas and energy drinks; convenience seems to be a marketing weasel word; and it is arguably easier to exceed safe dosage with tablets than with beverages. 89.134.199.32 (talk) 21:43, 7 June 2019 (UTC).

Proposed Improvements by Queen's University School of Medicine (Wikipedia Assignment)
Hello, we are a group of medical students from Queen's university. We are working to improve this article over the next month and will be posting our planned changes on this talk page. We look forward to working with the existing Wikipedia medical editing community to improve this article and share evidence. We welcome feedback and suggestions as we learn to edit. Thank you.

We are proposing several improvements to the Caffeine Wikipedia page.

2. Updating citations and recent data on Caffeine Withdrawal and Dependence (re: ICD-11 and DSM-V).
Change this: "Caffeine dependence can involve withdrawal symptoms such as fatigue, headache, irritability, depressed mood, reduced contentedness, inability to concentrate, sleepiness or drowsiness, stomach pain, and joint pain."

To this: "The diagnostic criteria for caffeine withdrawal require a previous prolonged daily use of caffeine . Following 24 hours of a marked reduction in consumption, a minimum of 3 of these signs or symptoms is required to meet withdrawal criteria: difficulty concentrating, depressed mood/irritability, flu-like symptoms, headache, and fatigue . Additionally, the signs and symptoms must disrupt important areas of functioning and are not associated with effects of another condition

Reference: Diagnostic and statistical manual of mental disorders (DSM-5®). American Psychiatric Pub. 2013. Randomassortment (talk) 04:35, 18 November 2019 (UTC)


 * Thank you for sharing this .Great work so far. I like how you shared the exact wording of what you propose to change. Would you be able to add your text book using the citation tool as we did together in class last week? Also, please include the page(s) that you found the info if this is a text book. Books can be added by pasting the ISBN into the citation tool and it should auto-populate the citation nicely. You can manually add in the relevant pages. JenOttawa (talk) 01:39, 19 November 2019 (UTC)

Original Target Sentences: The ICD-10 includes a diagnostic model for caffeine dependence, but the DSM-5 does not. The APA, which published the DSM-5, acknowledged that there was sufficient evidence in order to create a diagnostic model of caffeine dependence for the DSM-5, but they noted that the clinical significance of this disorder is unclear. The DSM-5 instead lists "caffeine use disorder" in the emerging models section of the manual.

Proposed Changes: The ICD-11 includes caffeine dependence as a distinct diagnostic category, which closely mirrors the DSM-5’s proposed set of criteria for “caffeine-use disorder”. Caffeine use disorder refers to dependence on caffeine characterized by failure to control caffeine consumption despite negative physiological consequences. The APA, which published the DSM-5, acknowledged that there was sufficient evidence in order to create a diagnostic model of caffeine dependence for the DSM-5, but they noted that the clinical significance of the disorder is unclear. Based on this clinical ambiguity, the DSM-5 classifies caffeine-use disorder as a “condition for further study”.

Sources:

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5. Arlington, VA: American Psychiatric Association; 2013. DSM-5

World Health Organization. (2018). International classification of diseases for mortality and morbidity statistics (11th Revision).

American Psychiatric Association (2013). "Substance-Related and Addictive Disorders" (PDF). American Psychiatric Publishing. pp. 1–2. Archived from the original (PDF) on 15 August 2015. Retrieved 18 November 2019. (MPBalanaser (talk) 03:44, 19 November 2019 (UTC))

3. Updating the symptoms and criteria that qualify caffeine intoxication.

 * Please include more info and your exact reference(s) here before we edit on the 25th. JenOttawa (talk) 01:39, 19 November 2019 (UTC)


 * - Original: The symptoms of caffeine intoxication are comparable to the symptoms of overdoses of other stimulants: they may include restlessness, fidgeting, anxiety, excitement, insomnia, flushing of the face, increased urination, gastrointestinal disturbance, muscle twitching, a rambling flow of thought and speech, irritability, irregular or rapid heartbeat, and psychomotor agitation.


 * - Proposed Change: Caffeine intoxication may be diagnosed if five (or more) of the following symptoms develop after recent consumption of caffeine: restlessness, nervousness, excitement, insomnia, flushed face, diuresis, gastrointestinal disturbance, muscle twitching, rambling flow of thought and speech, tachycardia or cardiac arrhythmia, periods of inexhaustibility, and psychomotor agitation. (Source: American Psychiatric Association (2013-05-22). Diagnostic and Statistical Manual of Mental Disorders. American Psychiatric Association. doi:10.1176/appi.books.9780890425596. ISBN 0890425558)

--- Sentence #1

Original Sentence:"Caffeine overdose can result in a state of central nervous system over-stimulation called caffeine intoxication (DSM-IV 305.90).[115] "

Modified Sentence:Caffeine overdose can result in a state of central nervous system over-stimulation known as caffeine intoxication, a clinically significant temporary condition that develops during, or shortly after, the consumption of caffeine.

Sentence #2

Original Sentence:"In cases of much larger overdoses, mania, depression, lapses in judgment, disorientation, disinhibition, delusions, hallucinations, or psychosis may occur, and rhabdomyolysis (breakdown of skeletal muscle tissue) can be provoked.[116][117]"

Modified Sentence:According to the International Classification of Diseases (ICD-11), cases of very high doses of caffeine (e.g., > 5 g) may result in caffeine intoxication with symptoms including mania, depression, lapses in judgement, disorientation, disinhibition, delusions, hallucinations or psychosis, and rhabdomyolysis (breakdown of skeletal muscle tissue) can be provoked. Very severe cases of caffeine intoxication may result in respiratory distress or seizures and can be fatal.

(Jasminelam845 (talk) 14:37, 19 November 2019 (UTC))Jasminelam845

4. Editing wording for the relationship between caffeine intoxication and death.
-     Original: Massive overdose can result in death.

-     Proposed Change: Death from caffeine ingestion appears to be rare; however, several hospitalizations ((79,438 emergency room visits attributable to caffeine overconsumption in the United States between 2005 and 2011) and some deaths from caffeine toxicity have been reported. (Source: Temple, Jennifer L.; Bernard, Christophe; Lipshultz, Steven E.; Czachor, Jason D.; Westphal, Joslyn A.; Mestre, Miriam A. (2017). "The Safety of Ingested Caffeine: A Comprehensive Review". Frontiers in Psychiatry. 8. doi:10.3389/fpsyt.2017.00080. ISSN 1664-0640)

5. Adding two new disorders to "Other Caffeine-induced Disorders" classified under DSM-V.

 * Thanks for this suggestion. Can you please share your exact wording and your reference here on the talk page? If it is a textbook, please include the page #s. JenOttawa (talk) 01:39, 19 November 2019 (UTC)

6. Editing the proposed guidelines for children and adolescents regarding caffeine consumption.
Cmoonqueens (talk) 20:13, 11 November 2019 (UTC)


 * Hello, yes sure please do so! I would be very interested to see these improvements Please just make sure to provide reliable sources with your changes, me and other editors can help you wrap things up neatly to Wikipedia's standards, but we can't invent sources  Signimu (talk) 19:00, 12 November 2019 (UTC)


 * Thank you, we have reviewed the Wikipedia guidelines for sources and will be including secondary sources MEDRS guidelines, in a couple weeks. We look forward to learning from you. Cmoonqueens (talk) 19:03, 12 November 2019 (UTC)


 * Great idea! I know many people who are interested in this (including my own kids as they watch me drink coffee...). Can you please share exactly what you propose to add (along with references). I see that you already mentioned these are coming soon in your reply below! JenOttawa (talk) 01:39, 19 November 2019 (UTC)

7. Adding two other caffeine-induced disorders classified under DSM-V but not under any categories of "common" disorders induced by caffeine intake.
Maryambzzz (talk • contribs) 19:13, 18 November 2019 (UTC)


 * Please see the comments above about sharing the wording of your improvement and also your citation. Note the comment above re text book and page #s if relevant to your source. Thank so much! Great work so far, all these ideas are great and will help improve this article that is read over 3000 times a day in english alone. See page view statistics here (if you are interested). JenOttawa (talk) 01:39, 19 November 2019 (UTC)

Dear thank you very much for your contributions, these will surely improve the article  Please take a moment to watch the following video, which will show you how you can use the citation tool to easily and quickly add references with a proper formatting and reuse them (this is very important here, but using this easy tool you don't need to understand how formatting works ). Thank you and please keep up your good work! --Signimu (talk) 14:38, 20 November 2019 (UTC)

Incorrect figures for caffeine solubility in water
I've checked the reference: [168] Susan Budavari, ed. (1996). The Merck Index (12th ed.). Whitehouse Station, NJ: Merck & Co., Inc. p. 1674.

Well, actually I checked the thirteenth edition but the sources are from 1905 so I'd wager the caffeine entry has not been updated.

This is from The Merck Index 13th edition: "Properties: Hexagonal prisms by sublimation, mp 238°.  Odorless with bitter taste.  Sublimes 178°.  Fast sublimation is obtained at 160-165° under 1 mm press. at 5 mm distance.  d418 1.23.  pH of 1% soln 6.9.  Absorption spectrum:  Hartley, J. Chem. Soc. 87, 1802 (1905).  One gram dissolves in 46 ml water, 5.5 ml water at 80°, 1.5 ml boiling water, 66 ml alcohol, 22 ml alcohol at 60°, 50 ml acetone, 5.5 ml chloroform, 530 ml ether, 100 ml benzene, 22 ml boiling benzene."

Monograph Number: 1636 Title: Caffeine CAS Registry Number: 58-08-2 Published originally as The Merck Index, Thirteenth Edition. Copyright © 2001 by Merck & Co., Inc., Whitehouse Station, New Jersey, USA. All Rights Reserved. Zeyus (talk) 19:15, 1 December 2019 (UTC)

Irrelevant citation?
In this page's info box (on the top right of the article on desktop view) the article says "Adults: 3–7 hours[6]" Looking at the citation, it does not actually say 3-7 hrs. It says about 5 hrs. Shouldn't the wiki article be changed to say "~5 hours" or "about 5 hours" rather than assuming it's 3-7?

The citation says: "   In an average-sized adult or child above the age of 9, the half-life of caffeine is approximately 5 hours. Various characteristics and conditions can alter caffeine half-life. It can be reduced by up to 50% in smokers. Pregnant women show an increased half-life of 15 hours or higher, especially in the third trimester. The half-life in newborns is prolonged to about 8 hours at full-term and 100 hours in premature infants, likely due to reduced ability to metabolize it. Liver disease or drugs that inhibit CYP1A2 can increase caffeine half-life.12,14 "

Further more, i looked for "Infants: 65–130 hours" on the citation by using ctrl-f "130" and the citation did not say that about infants. Infants should say "~8 hours" instead of 65 - 100, which is what the citation says.

I also lack the established user/Autoconfirmed status i believe. Disoff (talk) 12:54, 4 February 2020 (UTC)

Request to remove under-supported claim that caffeine increases heart rate
The introductory section says,

> Tolerance to the autonomic effects of increased blood pressure and heart rate, and increased urine output, develops with chronic use (i.e., these symptoms become less pronounced or do not occur following consistent use)

And cites the paper at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC370671/.

I appreciate that the main point being made here is that acute effects are tempered with chronic use, and I don't see any issues with that claim in either the cited paper or the wider literature.

The abstract of the cited paper takes as given that acute caffeine use increases heart rate; the paper itself is investigating chronic use. To justify the acute effects it assumes, it cites one paper by the same authors, that I think inspired this follow-up study. I don't have access to this previous acute-effects paper right now, but its abstract says something more nuanced than is stated in the later chronic-effects paper: "There was a slight fall and then a rise in heart rate".

This all might sound pedantic, but I've done a reasonably detailed review of studies that monitor heart rate alongside caffeine use, and I don't think there's a strong consensus that caffeine increases heart rate (intuitively surprising as this might sound). There are multiple studies showing a decreasing effect, multiple showing an increasing effect, and many showing no large effect.

Further, the later 'Pharmacology' section of the current version of this article states:

> Caffeine is an antagonist of adenosine A2A receptors, [...]

[...]

> Antagonism of adenosine receptors by caffeine also stimulates the medullary vagal, vasomotor, and respiratory centers, which increases respiratory rate, reduces heart rate, and constricts blood vessels.

Which suggests that caffeine has the opposite effect to that implied in the introduction.

To clarify, I'm certainly not claiming that caffeine has no cardiovascular effects, for example on blood pressure; I'm only claiming that the sign of the effect of caffeine on heart rate seems unclear enough that it is misleading to make a conclusion in passing, on the way to a later (seemingly justified) point about tolerance.

Concretely, I'd like to remove the reference to heart rate in the introductory statement about tolerance. I don't have enough edits to my account to make this change. I'm not picky about the exact wording, but if it were my choice, I'd replace the sentence with:

> Tolerance to the autonomic effects of increased blood pressure and urine output develops with chronic use (i.e., these symptoms become less pronounced or do not occur following consistent use).

I'm happy to keep the current reference, because it seems sturdy enough to my eyes in terms of the body of the work itself; it's only some assumptions it makes along its way that I'm wary of.

If it would help, I'm happy to link to the relevant studies I alluded to. I'm not a regular Wikipedia contributor, so let me know if I can do something more to clarify things! I just noticed this claim in the introduction and thought I should try to improve it.

Elliot marsden (talk) 12:06, 13 July 2020 (UTC)

Citation error & new meta-analysis
Could someone do this edit? I can't edit this article since its protected, but is cited twice within the article and the duplicate ought to be removed. There is also a new caffeine related meta-analysis (coffee is discussed specifically) about Alzheimer's available, which might be worth citing: ("These results do not support an association between coffee consumption and an increased risk of overall dementia or Alzheimer’s disease..." and another interesting bit within 30322179 is "There is also no support from Mendelian randomization studies that a genetic predisposition to consume more coffee is associated with a decreased risk of AD..."). 5-HT2AR (talk) 02:46, 21 December 2020 (UTC)
 * Thanks - duplicate ref removed. The new source is in a MDPI journal, which are generally undesirable, but the point it makes is not exceptional so might be usable. Alexbrn (talk) 05:41, 21 December 2020 (UTC)

"Coffee shakes" listed at Redirects for discussion
A discussion is taking place to address the redirect Coffee shakes. The discussion will occur at Redirects for discussion/Log/2021 July 5 until a consensus is reached, and readers of this page are welcome to contribute to the discussion. signed,Rosguill talk 19:19, 5 July 2021 (UTC)

Hair/baldness
Shampoos add caffeine to overcome genetic male pattern baldness. There is a research article that finds out it helps. Kindly add. — Preceding unsigned comment added by 2003:E9:3F1A:420:BC79:54A9:6F6F:FC99 (talk) 08:11, 16 July 2020 (UTC)
 * There are adverts on TV for shampoos and hair treatements with caffeine, but no explanations for why. There doesn't seem to be anything on this page about hair, shampoo or scalp treatment. Does anyone have any sources?

213.31.95.80 (talk) 12:13, 25 September 2021 (UTC)

Natural Occurences: unsupported claim
Hello,

I was interested in temperate climate plants that contain caffeine, and this article states in it's Section "Natural occurence":

"Temperate climates around the world have produced unrelated caffeine-containing plants."

However, no listing of such plants or a citation showing one. Other citations provided in the same section may list different plants containing caffeine, but none of them are from temperate areas but rather sub-tropical zones at best. I think since this is the "Natural Occurence" section, it should provide this information more in detail or be removed or changed if it can't be verified or proven.

Cheers

BusterTheBusta (talk) 12:49, 19 November 2021 (UTC)

Nomination of Caffeine (data page) for deletion
A discussion is taking place as to whether the article Caffeine (data page) is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Articles for deletion/Caffeine (data page) until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. DePiep (talk) 14:03, 14 January 2022 (UTC)

Link to data page
The link to the data page was removed in this edit with the justification not needed, the data page is fully redundant. It is only redundant if the result of the AFD is to delete. If the result is to keep, then Caffeine section will be deleted, and the data page will no longer be redundant. Please leave the data page link in place while the AFD discussion is proceeding so editors can compare the two solutions side by side. Boghog (talk) 17:31, 14 January 2022 (UTC)
 * Nope. The data is redundant. No harm is done when this links is not present, the article is OK. Obviously, you are editing an article to make a point in an AfD ie, off-mainspace. Quite a bad base for a mainspace edit. Anyway, you are editwarring. -DePiep (talk) 17:36, 14 January 2022 (UTC)
 * I strongly disagree. We are having a AFD and you delete the data page is under discussion before that discussion has completed which is completely unacceptable. You have also deleted a link to that data page.  It is essential that link remain in place for the AFD discussion. How can we possibly have a discussion about material that you have deleted?  Boghog (talk) 17:46, 14 January 2022 (UTC)

Semi-protected edit request on 21 January 2022
Please revert this edit. It introduced a typo ("promiment") and removed the connection the previous sentence ("several known mechanisms") had to the rest of the paragraph, making the paragraph no longer make as much sense. 130.208.182.103 (talk) 21:52, 21 January 2022 (UTC)
 * ✅. It also didn't even form a complete sentence itself. DMacks (talk) 22:47, 21 January 2022 (UTC)

Is Caffeine regulated in any parts of the world
3rd sentence:

"Unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world."

Is there a source? Why "nearly"? Only because the author was not 100% sure. I vote to delete this sentence.

Alternatively we add the countries that regulate caffeine but again, I couldn´t find any.

178.13.24.90 (talk) 09:07, 26 January 2022 (UTC)bb

An unclear sentence?
In section "Chemistry", there is the following sentence: "The pyrimidinedione in turn contains two amide functional groups that exist predominantly in a zwitterionic resonance the location from which the nitrogen atoms are double bonded to their adjacent amide carbons atoms". In my opinion, it is not clear. Perhaps, it should be rewritten.Ekisbares (talk) 18:29, 1 February 2022 (UTC)

ICDM should be ICD
ICDM is mentioned three times: twice as ICDM-9 and once as ICDM 9. The first mention of ICDM links to [|ICD], which has no ctrl-f instances of ICDM. A quick google search also redirects to ICD. Would like a second opinion on if this should be ICD in all cases. rex (talk) 16:32, 22 February 2022 (UTC)

“Darker roasts have more caffeine”
A quick search shows otherwise: A dark-roasted bean contains more caffeine than a light-roasted bean due to its stronger flavor. Not true. – Et0zl Talk&#x263B;  13:53, 30 May 2022 (UTC)

Semi-protected edit request on 8 July 2022
Mis-spellings in the text. "Judgement" should be "Judgment". Peterdkukla (talk) 10:02, 8 July 2022 (UTC)
 * ✅ RudolfRed (talk) 17:08, 8 July 2022 (UTC)

Narcolepsy treatment
This revert was justified because the source did not evaluate caffeine effects on narcolepsy specifically, but rather only included it in the discussion. The one source used here is primary research, too preliminary to justify including it in the article. Best to wait for a WP:MEDRS review on possible use of caffeine for treating narcolepsy, which a PubMed search shows is not available as of 2015, here. Zefr (talk) 14:05, 21 July 2022 (UTC)


 * Hi all, so I am trying to add the following sentence : "Caffeine has shown tentative evidence for narcolepsy" in the "Research" category of the article providing the following secondary and reliable reference: https://doi.org/10.2147%2Ftcrm.s244714 . User does not agree citing https://en.wikipedia.org/wiki/Wikipedia:Identifying_reliable_sources_(medicine) and the fact the evidence is weak and that a wikipedia article is not a news article. I would like to add that we can usually find the same type of claims being made in high ranked wikipedia bio-medical articles (cf https://en.wikipedia.org/w/index.php?search=tentative+evidence&title=Special%3ASearch&go=Go&ns0=1) What are your toughts on this disagreement ? Thanks to you all! Medhekp (talk) 14:07, 21 July 2022 (UTC)
 * I agree with Zefr; this research, based on a pilot study with only sixteen participants, is not suitable for use in Wikipedia. That other such stuff may be included in other articles is not a relevant argument. Richard Keatinge (talk) 09:45, 25 July 2022 (UTC)

Contradiction (of sorts): Under Adverse Effects - Psychological and Adverse Effects - Risk of Other Diseases
In the Adverse Effects - Psychological section, the quote is "Increased consumption of coffee and caffeine is associated with a decreased risk of depression" In the Adverse Effects - Risk of Other Diseases section, the quote is "Caffeine consumption may be associated with reduced risk of depression, although conflicting results have been reported." Both quotes cite references 99 and 100. I myself have not looked into the sources. These two sentences are contradictory. Migy007 (talk) 15:51, 25 July 2022 (UTC)
 * I removed the comment on depression from the "Risk of other diseases" section, as the topic is adequately covered under the Psychology section with this edit. Hope that helps. Zefr (talk) 17:51, 25 July 2022 (UTC)

Why its so detrimental to kids.
It actually stunts there growth. 72.201.35.99 (talk) 16:16, 3 September 2022 (UTC)
 * This is a verifiably false statement, as discussed with references in our article. DMacks (talk) 16:17, 4 September 2022 (UTC)

Caffeine in jet lag etc. reference point 55
The article referenced, in the first paragraph, says that it is “unclear” whether error or injury is effected by caffeine intake for those with jet lag or work shift disorder (or whatever it was called) whereas the Wiki article states that error is lessened by use of a caffeine. The facts between the two pages are not in agreement.

Thank you Wikipedia 2601:98A:4200:5BED:4135:2C64:ABAC:A208 (talk) 14:41, 21 January 2023 (UTC)