Frågor och svar kreatin v2

[Biffen91]

Hejsan, jag är ganska förvirrad.. Min kompis sägar att man bara blir tjock av kreatin, att det inte bygger muskler, stämmer det? Varför är det då typ det mest använda kosttillskottet?

[King Grub]

Din kompis pratar i nattmössan.

[Biffen91]

aa okej, tur det!

[Player]

När jag blandar kreatinprodukter (rena eller sammansatta med andra ämnen) får jag nästan alltid små korn som lägger sig i botten av glaset/shakern.

Jag tror egentligen inte att detta är kreatin som inte lösts upp, eftersom korn inte finns i det fina pulvret från början. (Har även provat med ljummet vatten och stora mängder vätska, utifall det skulle vara fråga om att vätskan blev mättad och meer pulver inte kunde lösas.) Istället funderar jag på om det kan vara en sorts biprodukt som uppkommer då pulvret löses i vatten.

Här ett klipp från FAQen på Samarin-hemsidan:
"Det finns ibland vita rester kvar i glaset, måste jag få i mig dem också?
Nej. Så länge du har låtit Samarin bubbla klart innan du dricker det finns den verksamma delen av Samarin i lösningen."

Eftersom denna rest ofta är jätteäcklig (ni som provat exempelvis Vault vet vad jag menar) skulle det va skönt att veta om man slipper dricka den. Det kan vara förhållandevis stora mängder, så är det nåt att få i sig så gör det nog skillnad.

[Racso]

Kanske tagits upp tidigare, men...

A growing body of evidence suggests that creatine (Cr) might exert protective effects in a variety of pathologies where oxidative stress plays a concausal etiologic role; furthermore, it has been recently reported that Cr displays direct antioxidant activity in a cell-free setting. However, at present, no research has been specifically aimed to directly test the antioxidant potential of Cr on oxidatively injured cultured cells. Here, the effects of Cr were studied using cultured human promonocytic (U937) and endothelial (HUVEC) cells, and murine myoblasts (C2C12) exposed to H(2)O(2), tert-butylhydroperoxide (tB-OOH) and, in the case of U937 cells, peroxynitrite. Cr (0.1-10 mM) attenuated the cytotoxic effects caused by the oxidants in all the cell lines; under our conditions, cytoprotection was invariably associated with elevation of the intracellular fraction of Cr but it seemed to be unrelated to the levels of Cr phosphate (CrP); Cr did not affect the activity of catalase (CAT) and glutathione peroxidase (GpX), but it prevented H(2)O(2)- or tB-OOH-induced consumption of the nonprotein sulfhydryl (NPSH) pool in U937 and HUVEC cells; mass spectrometry experiments showed that a 136 MW molecule, which is likely to represent an oxidation by-product of Cr, formed in reaction buffers containing Cr and H(2)O(2) as well as in cellular extracts from H(2)O(2)- or tB-OOH- treated Cr-preloaded U937 cells; finally, Cr cytoprotection appeared to be unrelated to chelation of Fe(2+). In conclusion, it is suggested that Cr exerts a mild, although significant, antioxidant activity in living cells, via a mechanism depending on direct scavenging of reactive oxygen (in particular hydroxyl radical) and nitrogen species.

Free Radic Biol Med. 2006 Mar 1;40(5):837-49. Epub 2005 Nov 2.

[Racso]

Hittar inget eller väldigt lite om påverkan vid långvarit kreatinbruk.

Om någon känner till en sån studie (även preliminära resultat), mottages det tacksamt.

[Racso]

Ursprungligen postat av Guddi

AFSSA har inte gjort en studie utan en rapport där de tittat på studier som redan finns (du kan läsa den här http://www.fda.gov/ohrms/dockets/DOC...-47-vol112.pdf)
Rapporten verkar ha blivigt kritiserad en del av olika organisationer men jag hittar inte huvudkällan till dem.

To whom it may concern:

There has recently been a rash of misinformation that has been spread around the world that has arisen from a statement made by a Mr. ? Dr. ? Martin Husch for the French Agency of Medical Security for Food (AFSSA), claiming a link between creatine monohydrate supplementation and cancer. This is not supported by the literature and it is unfortunate that medical misinformation can be spread throughout the world so rapidly. This agency claims to have reviewed the literature using nutritional experts (yet does not list them so we can judge their credentials), and the author has not published a single paper in a peer reviewed journal (at least none that have appeared in PubMed). I found the statement to be somewhat accurate in several areas (with the exception that it states that creatine increases muscle cell water (10 %) - this is high and it is more likely 3 - 4 %)). The MAJOR problems come when they/?he tries to make a comment about the potential side effects:


1. approximate translation of the AFSSA statement on cancer "considering that creatine and creatinine under certain circumstances, particularly in the presence of simple sugars and elevated amino acids, could have carcinogenic effects based on preliminary experimental arguments in vitro and in vivo have been equivocal". [I am not aware of any studies showing that creatine taken with sugar and amino acids is carcinogenic - especially when taken in physiological amounts - any compound, even amino acids may be carcinogenic in high doses (see MSDS label on leucine!)]. The real issue comes with the statement that "with the potentially carcinogenic effects..." - this is unfounded and certainly the jump to stating that epidemiological studies have shown a link is complete fabrication and misinformation. This sort of misinformation is as bad as the health care fraud that some folks claim regarding unproven agents. I do agree that we need to concern ourselves about impurities in creatine and any unregulated substances (ie. Problems previously with tryptophan and eosinophilic myositis) and I am all for creatine and other nutraceuticals being exposed to rigorous purity testing by federal agencies - I do know that most of the creatine for the neurology studies is exposed to careful testing for impurities and other chemical standards - Many of the large reputable companies in the US and Canada buy their creatine from high quality sources.


It then goes on to say that the effects of high levels of creatine ingestion has not been studied in the short or long term (yet they claim there have been epidemiological studies). They quote that there are epidemiological studies showing difficulties with digestion, muscle cramps and apparently cardiovascular problems ( - not sure where this comes from * there are in fact 2 studies in humans with congestive heart failure showing benefits to performance and studies in animals showing cardioprotective effects and we have shown that it does not affect blood pressure (Mihic, et al, Med Sci Sports Exerc, 2000)). There are other issues with this * firstly there have been no true epidemiological studies of creatine use and papers are suggesting from this article that epidemiological studies show a possible risk * THIS IS ABSOLUTELY INCORRECT.

In the final summary they state that supplementation with creatine constitutes a risk, but it has been insufficiently evaluated, particularly in the long-term. With the potentially carcinogenic effects, it would be necessary for the regular reevaluation of studies.

I am shocked that this amount of misinformation can be placed on the internet by such and agency claiming legitimacy and trying to advocate for the good of people. This type of speculative misinformation does not serve the interests of anyone. Our group and others are carefully evaluating the risks and benefits of creatine monohydrate ingestion in patients with neuromuscular and neurometabolic disorders as well as in human aging * Patients reading this stuff in the papers have already called to drop out of studies. Creatine may be very helpful in a number of medical conditions and thanks to this inaccurate statement we will all have difficulty in recruiting and retaining subjects. Unfortunately, it is very difficult for the lay public to evaluate the quality of the information and the AFSSA statement violates many of the key factors to look for in judging legitimacy:

1. The person signing their name to the statement does not list their credentials.
2. The supposed scientists who evaluated the literature are not listed.
3. There is no evidence of external review of the statement.
4. The statement has internal inconsistencies (medium and long term studies not done and yet concludes that epidemiological studies show their may be a cancer risk).
5. There are no references to peer reviewed studies to support the statement.

THERE ARE NO STUDIES IN HUMANS EVEN SUGGESTING AN INCREASED RISK OF CANCER WITH CREATINE.

There are many papers showing an anti-cancer effect of creatine analogues in animals:

Jeong KS, Park SJ, Lee CS, Kim TW, Kim SH, Ryu SY,
Williams BH, Veech RL, Lee YS.Effects of cyclocreatine in rat
hepatocarcinogenesis model. Anticancer Res 2000 May-Jun;20(3A):1627-33

Kristensen CA, Askenasy N, Jain RK, Koretsky AP. Creatine and cyclocreatine
treatment of human colon adenocarcinoma xenografts: 31P and 1H magnetic resonance
spectroscopic studies. Br J Cancer 1999 Jan;79(2):278-85

Schiffenbauer YS, Meir G, Cohn M, Neeman M. Cyclocreatine transport and
cytotoxicity in rat glioma and human ovarian carcinoma cells: 31P-NMR spectroscopy.
Am J Physiol 1996 Jan;270(1 Pt 1):C160-9

Ara G, Gravelin LM, Kaddurah-Daouk R, Teicher BA
Antitumor activity of creatine analogs produced by
alterations in pancreatic hormones and glucose metabolism.
In Vivo 1998 Mar-Apr;12(2):223-31

Miller EE, Evans AE, Cohn M. Inhibition of rate of tumor growth by creatine
and cyclocreatine.Proc Natl Acad Sci U S A 1993 Apr 15;90(8):3304-8



There are several reviews of creatine so people can get their facts straight:
Casey A, Greenhaff PL Does dietary creatine supplementation play a role in skeletal muscle
metabolism and performance? Am J Clin Nutr 2000 Aug;72(2 Suppl):607S-17S

Tarnopolsky MA Potential benefits of creatine monohydrate supplementation in the elderly.
Curr Opin Clin Nutr Metab Care 2000 Nov;3(6):497-502

Terjung RL, Clarkson P, Eichner ER, Greenhaff PL, Hespel PJ, Israel RG, Kraemer
WJ, Meyer RA, Spriet LL, Tarnopolsky MA, Wagenmakers AJ, Williams MH American College of Sports Medicine roundtable. The physiological and health effects of oral creatine supplementation. Med Sci Sports Exerc 2000 Mar;32(3):706-17

Wyss M, Kaddurah-Daouk R. Creatine and creatinine metabolism. Physiol Rev 2000 Jul;80(3):1107-213

There are several reviews of safety:
Poortmans JR, Francaux M Adverse effects of creatine supplementation: fact or fiction? Sports Med 2000 Sep;30(3):155-70

Mihic S, MacDonald JR, McKenzie S, Tarnopolsky MA. Acute creatine loading increases fat-free mass, but does not affect blood pressure, plasma creatinine, or CK activity in men and women. Med Sci Sports Exerc. 2000 Feb;32(2):291-6.

Terjung RL, Clarkson P, Eichner ER, Greenhaff PL, Hespel PJ, Israel RG, Kraemer
WJ, Meyer RA, Spriet LL, Tarnopolsky MA, Wagenmakers AJ, Williams MH American College of Sports Medicine roundtable. The physiological and health effects of oral creatine supplementation. Med Sci Sports Exerc 2000 Mar;32(3):706-17

I would hope that Reuters, ESPN, National Post, Associated Press, etc. would get their facts straight before they put out misinformation. I know that a flashy inflammatory and inaccurate statement is better for press, but please think of the patients who are involved in the studies and those who may stand to benefit from carefully controlled evaluation of the risks and benefits of creatine supplementation. Yes, there may be some side effects, but please, let the researchers evaluate what these are and the incidence so that people can evaluate the risks and benefits of supplementation in an unbiased manner.

Sincerely,


Mark Tarnopolsky, MD, PhD, FRCP(C),
Neuromuscular Disease Unit, 4U4 Neurology,
McMaster University Medical Center,
Hamilton, Ontario, CANADA, L8N 3Z5
1-905-521-2100 (x75226/76593).
FAX 905-521-2656.
tarnopol@mcmaster.ca

http://www.diet-coaching.com/creatine.html

[Racso]

Mer kritik mot den franska rapporten (visserligen från ett kosttillskottsbolag, men argumenten håller)

Distorted Report by French "Scientists" Claims Creatine Causes Cancer.

Is it safe? Does it increase the risk of cancer? Does it cause kidney problems?

By Paul Cribb B.H.Sci.HMS.Honors. Exercise Physiologist


--------------------------------------------------------------------------------

shock wave went right through the international sporting and athletic community on January 23rd 2001, when the Agencies Francaise de Securite Sanitaire des Aliment (AFSSA), (French Agency for Medical Security for Food) commissioned by the French government, issued it's report on the safety and effectiveness of the supplement creatine monohydrate. Not only did the French report state that creatine as a supplement is ineffective, but that it also increases the risk of cancer. As usual, without bothering to check the facts the media ran with it better than Emmit Smith 30 yards out, ever could.

Up to 75% of NFL players use some form of creatine supplement, it's also used by the US Navy SEALS(1). Reports reveal that over 90% of US bodybuilders and weightlifters are devoted users of creatine(2). While a survey in England showed that over 57% of elite British athletes use creatine regularly(3).

Unlike athletes, journalists don't concern themselves with letting other teammates down. They are never accountable for their actions. Because of the media's gross irresponsibility and now even the so called French scientists, many coaches and team medical staff of various sports are now concerned about the consequences of encouraging creatine use by their athletes.

If anyone had bothered to translate the 50 page French review of creatine complete with over 230 references, they would find it to be one of the greatest scientific literature atrocities of the modern age. The entire review is misinterpreted research, downright lies, and complete fabrications about the science on creatine supplementation. It even questions the character and integrity of expert American scientists (page 16) whose research has demonstrated beneficial effects with creatine. In fact, according to AFSSA and the French government, the rest of the world is under a "creatine spell"(4).

Could this have anything to do with France's tyrannical attempt to control their athletes? They demonstrate this with their Nazi-like approach every year during the Tour de France. They raid athlete's rooms in the middle of the night. They force them to take drug tests with threats of arrest if drugs are detected. This is the police that force the athletes to take drug tests beyond what the governing cycling organization mandates. And you thought this type of tyranny and propaganda went out out with fall of the Berlin Wall.

I encourage everyone to look at the French literature, translate the report, then examine the references cited by AFSSA. What you will find are gross inaccuracies and outlandish interpretations (and I'm being polite). If you believe the French scientists report; not only is creatine totally ineffective, but it should drop anyone stone dead that uses it, and leave his or her family with the plague! In all seriousness, I have not seen such an example of blatant propaganda since a little fool with a funny mustache started invading European countries in the early 1940s.

I'm a scientist and to see "colleagues" obtain media recognition for what clearly is manipulated research interpretation to further a scientifically invalid agenda greatly disturbs me. It's no different than screaming "fire" in a crowded theater when there is none.

The Bogus Cancer Claims

In an attempt to cut through the BS I contacted Dr Jean-Louis Bertha, the food and safety expert at AFSSA and asked to be provided the exact research regarding creatine supplements increasing the risk of cancer. These are the study references quoted by DR Bertha via email on Thursday, February 8th 2001, 3:44pm, regarding creatine supplements increasing the risk of cancer.

Laser Reutersward, A., Skog, K., Jagerstad, M. 1987. Mutagenicity of pan-fried bovine tissues in relation to their content of creatine, creatinine, monosaccharides and free amino acids. Food Chem. Toxicol 25: 755-762.

Anari M.R., Josephy P.D., Henry T., O'Brien P.J. 1997. Hydrogen peroxide supports human and rat cytochrone P-450 1A2-catalyzed 2-amino-3-methylimidazo (4 5-f) quinoline bioactivation to mutagenic metabolites: significance of cytochrome P-450 peroxygenase. Chem Res Toxicol 10: 582-588.

Felton J.S., Gentile J.M. 1997 Special issue "Mutagenic: carcinogenic N-substituted aryl compounds". Muta Res 376: 1-272.

Hammons G.J., Milton D., Stepps K., Guengerich F.P., Tukey R.H., Kadlubar F.F. 1997. Metabolism of carcinogenic heterocyclic and aromatic amines by recombinant human cytochrome P450 enzymes. Carcinogenesis. 18: 851-854.

Wyss, M., Kaddurah-Daouk, R. 2000. Creatine and creatinine metabolism. Physiol Rev 80: 1107-1125.
Obviously, DR Bertha must think everyone else on this planet is an idiot. If you read these reports, it is clear that they have nothing to do with creatine supplementation increasing the risk of cancer. These reports don't even mention the matter. In fact, these reports have nothing to do with creatine supplementation whatsoever.

These reports actually discuss the various mutagens (amino-imidazo-azaarenes or AIAs) formed during the cooking (frying) of meats. Meat is a naturally high source of creatine. According to these reports AIA mutagens are formed when meat is fried at 200 degrees C for 3 minutes.

Now, I may not be the smartest guy, but, what the hell does frying meat at 200 degrees C have to do with athletes taking creatine supplements? Absolutely nothing.

Incredibly, these research papers quoted by the French scientists demonstrate that these AIA mutagens are not carcinogenic as such, they are metabolically inert and must be activated by a series of enzymatic processes to exert any active effect (Wyss page 1164; Hammonds et al. pages 851-854).

Further examination of these reports reveal that the AIA mutagens were in fact generated from invitro (lab dish and model) experiments, not humans. Similar mutagens have been found performing experiments with sugars and various amino acids(5).

I'll just be polite at this point and suggest the scientists at AFSSA don't know how to interpret literature very well.

Incidentally, for those that love their steak and are truly concerned, not frying foods and using marinades and oil instead of butter can minimize generation of AIAs(5). A more recent calculation based on extensive literature review of levels of AIAs in cooked foods and mean food consumption figures in the US indicate an incremental cancer risk of 0.00001% (6,7). You were at a higher risk of being knocked down when crossing the street this morning. This is the carcinogenic evidence the French scientists are putting forward regarding creatine supplements.

By no stretch of the imagination could this data be applicable to athletes consuming creatine monohydrate supplements. Is this dishonest, deceitful and extremely pathetic on AFSSA part? Indeed.

Not only are there no studies whatsoever indicating in even the wildest possible interpretation that supplementing with creatine could even remotely cause cancer, but their literature support for their statements does not even involve creatine.

The sad part of all this is that the media will report this through thousands of news outlets throughout the world effectively propagating an outright lie. It stinks.

Bogus Toxicity Claims

The report put forward by the AFSSA scientists instills such a fear for concern regarding toxicity from creatine supplements you would think ingestion of a teaspoon full would have you oozing green slime while falling down dead in your tracksuit. However, once again their quoted scientific evidence comes up short, real short. And their knowledge of clinical applications of biochemical pathways is sadly lacking.

Of the 230 odd studies cited by the French scientists in their report, not one indicates, let alone demonstrates any form of toxicity regarding creatine use in healthy people. Not a single one. The only straw these scientists could grasp at was a biochemical pathway for the nitrosation of creatine and creatinine (the waste product of creatine) that is of concern only to those with chronic renal (kidney) disease. However, they couldn't even get the biochemistry right on this one (8).

Of the 230 odd references cited by the French scientists in their report, not one controlled study indicates, let alone demonstrates any form of toxicity regarding creatine use in healthy people. Not a single one.

N-nitromethylamine (a carcinogen) is the end product of a series of several nitrite reaction sequences of creatine to form N-nitrosarcosine. Sarcosine is not a toxin as the French report suggests. Nitrosation of creatine and creatinine has so far mostly been examined invitro systems (lab dish stuff) and it has only been suggested to be formed in uremic (chronic renal failure) patients due to the unique characteristics of this disease(5,8).

A comprehensive and recent review (ironically, also cited by the French) on creatine and creatinine metabolism demonstrates this nitrosation pathway to be inconsequential to a healthy body(5,8).

This is how far these so called scientists were willing to stretch research findings to deceive the athletic community and regulatory agencies and it sickens me. These are supposed to be scientists yet they ignore and even worse, distort the science.

Bogus claims about creatine and renal function.

Without citing any controlled research the French report warned of the dangers of kidney malfunction from creatine use and even attributed the onset of some kidney diseases to creatine supplementation. However, the French scientists forgot to mention the research conducted on athletes that directly assessed renal function.

Several studies demonstrate creatine supplementation does not increase or alter glomerular filtration rates(9) or any indices of renal and liver function for that matter(10). Also, long-term creatine supplementation (up to 5 years) does not impair the kidney function of athletes in any way(12).

Long-term research with athletes using creatine supplements shows their creatinine levels stay within a normal, healthy range. (Just the same as people not using creatine(31)). These studies examined glomerular filtration, tubular reabsorption and glomerular membrane permeability and none were affected by taking creatine supplements in real-life dosages that are used by athletes (20 grams a day for 5 days, then 3 to 10 grams every day there after).(13)

The Facts

How did this misinformation all start? In 1998, a single case report published by two British nephrologists in the journal Lancet documented the case of a 25-year-old man with an 8-year history of focal segmental glomerular scleosis (a chronic renal condition) with frequently relapsing corticosteroid-responsive nephrotic syndrome(14). The man was also being treated with cyclosporin, an immunosuppressive drug that is well known for its nephrotoxicity(11). He started taking a creatine supplement, 15 grams a day for 7 days, and then 2 grams a day for 7 weeks. His glomerular filtration rate dropped by 50% but returned to normal upon cessation of the creatine supplement.

Three days after this publication the French sports newspaper L'Equipe reported that creatine is dangerous for the kidneys in anyone that uses it. (15) This "news" was then taken up by several other European newspapers that claimed creatine induces renal and liver malfunction and even death(16-18). Completely untrue.

If anything positive could come out of this disgraceful sham disguised in a thin vale of scientific shenanigan is the importance of understanding your degree of health. If you have a preexisting renal dysfunction or you are at high risk of renal disease (diabetes or a family history of kidney disease), it is recommended that you are monitored regularly. It is also important to note that many athletes do not know if they have a preexisting kidney condition. All athletes should have their kidney function assessed. Ask your physician for an excess albumin excretion (>20mg/min) in urine collected under resting conditions, i.e. after 20 minutes of physical inactivity(11).

More fodder (Australian slang for "bullshit") for the media was cultivated from the death of three wrestlers who performed very extreme fluid restriction and other weight loss strategies. The Center for Disease Control concluded in their report that the regimen of chronic fluid restriction and intense exercise in the heat and not creatine is what resulted in hyperthermia/vascular collapse that contributed to the wrestlers deaths(19).

Creatine and Cardiovascular Complications.

The French report extracted a few anecdotal reports of hypertension among athletes using creatine from the US FDA database. Anecdotal is defined as untrustworthy and unreliable and regarding scientific investigation, this is exactly what the FDA and its database are demonstrated to be (see The Ephedra Report). Very unreliable and even manipulated to further their specific agendas.

Once again the French review ignored the real research on this matter. The scientific research. Double blind, tightly controlled studies demonstrating that high dose, short-term creatine loading (20 grams a day for 5 days) did not effect systolic, diastolic, or mean blood pressure in men or women (20). Other research has demonstrated the same thing with long-term creatine supplementation as well(21). It also important to note that creatine supplementation did not alter blood pressure in patients with congestive heart failure(22,23). Heart pump function was directly assessed in one of these studies and the creatine supplementation did not alter cardiac performance(23). Why the French ignored this research in favor of unreliable anecdotal grasps only strengthens the assumption of an ulterior motive for their distortion and their lies.

Heat Stress and Cramping.

There have been reports of muscular stiffness, strains, and cramping in athletes taking creatine. However, in controlled studies the evidence shows that creatine supplementation does not cause muscular dysfunction and/or complication in healthy people(24,25) or patients with various neuromuscular diseases(26). In fact, one recent study went so far as attempting to induce cramping in athletes by exercising them to varying degrees of dehydration(27). No differences were reported between those taking creatine and those taking a placebo. This study clearly demonstrated that there was no greater incidence of cramping associated with creatine use in athletes even under various dehydrated states.(27)

Conclusion

The clear facts are these, many scientists from around the world have independently published extensive reviews on creatine supplementation. Ira Jacobs of Canada(28), Jacques Poortmans and Marc Francaux of Belgium(13), Richard Kreider from the US(29), Markus Wyss of Switzerland(30) and a roundtable discussion of the literature written for the American Collage of Sports Medicine by thirteen of the worlds leading experts on creatine(31). Each review has examined well over 100 research studies on creatine use. (I urge you to read them.) Each review validates the effectiveness and safety of creatine supplementation, particularly when used in dosages that are shown to increase muscle mass and performance.

These French scientists are obviously puppets used to further France's desire to control the actions of their athletes and falsely influence athletes and regulatory agencies around the world. All through ignoring or distorting the real science.

The scientific and medical community has been dealt a serious blow to their credibility by this shameful and disgraceful manipulation of the facts by these scientists. And their actions are a spit in the face of the true scientists that have devoted their time, energy, and efforts in quest for the truth so we can advance our knowledge, our performance, and our health.



References

1. Schneider K, Harvig L, Ensign WY. Med Sci Sports Exerc.30:S60,1998

2. Williams MH, Kreider RB, Branch JD. Creatine: the power supplement. Champaign (IL):Human Kinetics,1999.

3. Harris N, Arthur C. The independent, Dec8:4 1998.

4. Miquel P. Le Monde. Aug14:15 1998.

5. Wyss, M., Kaddurah-Daouk, R. Physiol Rev 80: 1160-1167.2000.

6. Layton DW et al. Carcinogenesis. 16:39-52,1995.

7. Gold LS et al. Cancer Lett.83:21-29,1994

8. Wyss, M., Kaddurah-Daouk, R. Physiol Rev 80: 1173-1176.2000.

9. Poortmans JR, Francaux M. Eur. J. Appl. Physiol.76:566-7,1997.

10. Robinson TM et al. Br.J. Sports Med.34:284-288,2000.

11. Poortmans JR, Francaux M. Lancet (reply letter);352:234,1998.

12. Poortmans JR, Francaux M. Med. Sci.Sports Exerc.31:1108-10,1999.

13. Poortmans JR, Francaux M. Adverse effects of creatine supplementation: fact or fiction. Sports Med.30(3):155-170,2000.

14. Pritchard NR, Kalra PA. Lancet.351:1252-3,1998.

15. La creatine dangereuse? L'Equipe. April28:10,1998

16. Nau JK. Le Monde Nov.21:24,1998

17. Daulouede C. Sport et Vie. Nov 58,1998.

18. Haget H. Le Vif/L'Express. Oct 30:114,1998.

19. Control CFD. MMWR 47:105-108,1998.

20. Mihic SJR, et al. Med.Sci.Sport Exerc.2000.

21. Peeters BM, Lantz CD, Mathew JL. J.Strength Condit. Res.13:3-9,1999.

22. Andrews R, et al. Eur. Heart J. 19:617-622,1998.

23. Gordon A, Hulman E, Kaijser L. Cardiovas. Res.30:413-418,1995.

24. Kreider RB, Ferreira M, Wilson M et al. Med.Sci.Sports Exerc.30:73-82,1998

25. Vandenberghe K, Gaoris M, et al. J.Appl Physiol.83:2055-63,1997.

26. Tarnopolsky M, and Martin J. Neurology. 52:854-857,1999.

27. Vogel RA, Webster MJ, Erdmann LD and Clark RD. J. Strength Condit. Res. 14(2):214-219.

28. Jacobs I. Dietary creatine supplementation. Can.J.Appl.Physiol.24(6):503-514

29. Kreider RB. Creatine: The next ergogenic supplement? http://www.sportssci.org/traintech/creatine/rbk.html

30. Wyss, M., Kaddurah-Daouk, R. Creatine and creatinine metabolism. Physiol Rev 80: 1107-1213.2000.

31. Terjung RL, Clarkson P, Eichner ER, et al. The physiological and health effects of oral creatine supplementation. Med.Sci.Sports Exerc.32(3):706-717,2000.

[Choc]

Vad händer om man käkar kreatin när man inte tränar? Går man upp i vikt (i vatten) i alla fall?

[King Grub]

Vattenvikt, men det händer inget positivt med prestationsförmåga eller kroppssammansättning.

[shape]

"Det finns inga data på hur mycket kreatin man kan inta vid ett tillfälle men det är troligt att biotillgängligheten är större vid ett intag av 5g än vid ett intag av 10g [1]."
- Av ren kuriosa, vilka studier eller vetenskap syftar på detta, att biotillgängligheten skulle vara större vid 5g än tio, och skulle detta även gälla vid doser över 10 g?

[King Grub]

Den lilla ettan [1] bakom uttalandet visar vilken av referenserna du är intresserad av.

[Hultkrantz]

Ursprungligen postat av Guddi

En del kreatinprodukter säljs tillsammans med en pH buffert då det påstås att kreatin bryts ner väldigt fort till kreatinin i vätska. Nedbrytningen av kreatin till kreatinin är som störst vid pH 3. I magsäcken ligger pH kring 1 och det tillsammans med den korta tiden som kreatin är i magsäcken gör det inte så troligt att några större mängder kreatin går förlorade [1].

Det verkar som om man medicineras med protonpumshämmare typ omeprazol (losec) kommer pH i magsäcken att höjas till runt 4, varför en pH buffert skulle kunna utgöra en önskevärd funktion för dessa personer.

http://www.janusinfo.se/imcms/servle...c?meta_id=4269

[Threader]

Skulle villja påpeka en sak för de som funderar på att börja med kreatin, men tvekar pga vattenansamling: Jag, liksom de flesta jag känner som använder kreatin (känner till och med en bodybuilder som under tävling på internationell nivå använde kreatin!), märker inte visuellt av de vattenansamlingar som kreatin ger. Pratade lite med personalen på västerås budo&fitness butik idag (en fd bb som faktiskt också använde kreatin under tävling), och hon trodde att ansamlingarna syns hos de som överdoserar kreatinen (även om jag personligen tror att det kan variera, om än rätt lite, från person till person som det mesta gör).
Har ingen källa/studie att hänvisa till, utan bara personlig erfarenhet (kanske inte så trovärdigt när det kommer från en anonym person över internet, men i alla fall!), men jag hoppas att det gör folk mindre rädda för kreatin! =)

/Erik

[Xealswe]

Ursprungligen postat av bergelin

Låter underligt med tanke på att det finns naturligt i kött...

Fransmän vet ju inte om detta, dessa mustaschprydda, randigt klädda smala typer äter ju som bekant enbart grodlår, sniglar och baguetter