creatine safety issues
- Thanks everybody for your interest on this issue. The replies I have
received have generated some interesting ideas on creatine safety. The
following I find particularly interesting:
<<EJAP.doc>> <<EJAP_tab.doc>> <<ATT00155.txt>>
In this study the authors found definitive evidence that increase in
body weight is due to dry matter growth, as opposed to water retention:
"The creatine-group increased the absolute value of Total Body
Water and Intra-cellular Water, but not the relative value, which
indicates that the body mass gain following a medium-term creatine
supplementation is not due to intra-cellular water retention but
probably due to dry matter growth accompanied with a normal volume of
If this is a fact, then the possible causes of this growth need to be
If creatine has an influence on growth hormone regulation(as
hypothesised), there is an obvious need for concern. In fact, any
regulation of the cellular chemistry should not be taken lightly.
To return to the topic of strains and cramps, I think this study may
pose a possible answer:
Cr supplementation increases skeletal muscle hypertrophy, as above.
This results in increased muscular strength. It is possible that the
increased power is too much for the tendons, unless they can remodel as
fast as the muscle increases strength.
This problem is believed to occur in cases of steroid abuse. If
creatine is now believed to have similar anabolic properties, then this
could be seen be a cause of muscle strain or cramp.
Also, do we know what effect creatine will have if taken with anabolic
steroids, or even ACE stacking?
As pointed out by Dr. Kreider, creatine supplementation is probably safe
for, and may have positive effects on, the majority of people when taken
at recommended doses. However, many people who supplement, with or
without ergogenic drugs, will not be as knowledgeable as Dr. Kreider et
al and are likely, through misuse, to experience any potential
side-effects that might result. If they're told 20g Cr is good,
there'll always be people who'll take 50g.
Your opinion would be much appreciated.
Science and Technology
Food Safety Authority of Ireland
Lwr. Abbey St.
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- On the 3rd March 1999 a communication was sent to the Sportscience Forum
entitled "Creatine Safety Issues".
Some of you may have received a copy of a pre-published journal article
included in this communication. The article was circulated due to a
confusion among myself, the author, and the list moderators. This
journal article was not intended for circulation on the World Wide Web,
and is protected by copyright.
I would ask you now to please refrain from circulating the article any
further. Your understanding on this matter would be much appreciated.
- On Thu, 4 Mar 1999, Richard B. Kreider, PhD wrote:
> Several studies have reported gains in FFM after 7 to 14-d ofI read Ziegenfuss but not yours, couldn't get a hold of the journal.
> supplementation. For example, see Kreider et al., IJSN, 1996 (DEXA
> measured at 7, 14 and 28-d reported gains of 1.3 kg, 2.4 kg, and 2.2 kg in
> FFM in subjects ingesting a carbohydrate/protien supplement containing 20
> g/d of creatine versus a CHO placebo and a higher calorie
> carbohydrate/protein powder). See also the Ziegenfuss (MSSE, 1997)
> reporting an 8% increase in muscle thigh volume determined by MRI after 5-d
> of supplementation. I agree that more research is need here but comments
> are not "purely specualtive".
Thanks for the reference.
>I am not in disagreement with increases in FFM being observed following
> Muscle is about 80% water. A 595 g increase in protein content would be
> equivalent to about a 3 kg increase in muscle mass.....
>.... Over 20 studies now have reported gains in FFM following creatine
> supplementation (mostly longer term studies) with gains in FFM as great as
> 5.5 kg in 6 weeks. No study has reported a disproportionate increase in
> body water which can completely explain the weight gained. Finally, two
> studies have reported gains in muscle fiber diameter in response to
> long-term creatine supplementation. My point is not to say that the weight
> gain is only a result of increased protein synthesis but rather to point
> out that suggesting its only water is probably too simplistic. As I
> indicated in several of my reviews and articles, fluid retention, increase
> protein retention/synthesis, and/or a training induced increase in FFM
> probably all play a role when ingesting creatine during training.
acute or chronic loading protocols. I am quite aware of the changes in
these areas. My question is what is the signal for this. Does creatine
bind a transcription factor initiating the expression of immediate early
response genes and further protein expression down the road. I don't
think there is a shred of evidence to support this, but this is what is
being implied. Statements such as "creatine directly stimulates protein
synthesis" are innaccurate, for this has never been demonstrated. I feel
it is a secondary effect of training harder and energy balance.
I am conjecturing just as much as anyone else, but I am willing to admit
that certain facts are not known. I feel it is irresponsible for some to
quote some of their theories as facts until further evidence turns up.
> >VO2:I am familiar with much of Conway's work but have not read this book. I
> I would suggest reading the literature in this area before suggesting it is
> not justified. I suggest starting with the following book which covers
> this area in detail.
> Conway, M.A. and Clark, J.F. Eds. 1996A. Creatine and creatine
> phosphate:scientific and clinical perspectives. San Diego, CA:Academic Press.
am not stating that they are wrong, I'm merely making the point that
taking their work and turning it into a plus for creatine use
is not justified. There is no evidence that creatine supplementation will
improve aerobic performance. As well, I again point you to the work of
Adams and Baldwin at UIC where they performed creatine depletion
experiments on animals and the rats turned out fine. It really throws a
wrench into any theories along the lines that were suggested.
>I read the rebuttals but have to say that neither side won. Only research
> Yes, and this case report was criticised in the following letters to the
> Greenhaff, P. 1998. Renal dysfunction accompanying oral creatine
> supplements. Lancet 352:233- 234.
> Poortmans, J.R., and Francaux, M. 1998. Renal dysfunction accompanying oral
> creatine supplements [letter]. Lancet 352:234.
down the road will say. I personally don't think there is any risk to
normal healthy individuals, but that does not mean that the case study did
not make a valid point for some populations.
>I agree. I don't think we can safely say that creatine would be an
> The Earnest study evaluated 8 weeks of supplementation (20 g/d for 5-d and
> 10 g/d thereafter) in middle-aged hypertriglycerimic subjects involved in a
> fitness exercise program. The Kreider study (MSSE, 1998) evaluated
> creatine supplementation (16 g/d for 28-d) in college football players
> engaged in resistance/agility training..... Much more work needs to be done
> in this area before definative conclusions can be drawn.
effective anti-cholesterol drug at this time.
>I think 4-7 day studies are important for understanding mechanisms. Of
> Most of these studies are only 4 to 7-d of supplementation with small
> n-sizes. Some studies show no effect on single sprint performance.
> However, others show an effect particularly in longer supplementation
> trials. It is my view, from evaluating the literature, that you may see
> benefits following short-term supplementation but greater benefits can be
> seen when taking creatine during training...
course creatine will lead to numerous improvements over the long term, for
it allows an athlete to train harder. I think the haunting question is
why single bout performance is not improved whil multi-bout is.
> Numerous studies have evaluated the effects of creatine supplementation onThe problem is that too many studies of this nature have been performed.
> various performance tests. One of the principles of doing ergogenic aid
> research is that you conduct studies using athletes in order to determine
> the ergogenic potential in a "real world" setting. The ultimate test of an
> ergogenic aid is that it works in athletes in a competitive or simulated
> competitive setting.... Football players are also a population that
> heavily uses creatine. Thus, it is an excellent population to study to
> determine if creatine really works or not.
For example, if we relied on the outcomes of your study we would have to
say that long term creatine supplementation improves the bench press and
the first 5 bouts of a sprint cycle protocol, while creatine was not
effective in improving squat or power clean performance. There are a lot
of other studies with similar findings. If one could determine the
mechanism of creatine action, then its usefulness in a variety of sports
settings could be implied and better practical research could be
> I'm not sure who your are talking about or what you are implying with thisIt would be unprofessional to name names for not all of them are present
to defend themselves, but reading a lot of muscle magazines will bring you
across a few of them. My take home message for any researchers in this
field is to state the facts as facts and the theories as theories and this
field will gain much more credibility. It is all right to have a point of
view and state an argument, but researchers should be careful of what they
put in print. Once in print it is hard to change course.
I am well aware of the sacrifices made by researchers. I am living it.
Perhaps for me it is easy to criticize such research for my livelihood
does not depend on it. But from what I have observed, there are few
people willing to step forward and challenge people such as yourself.
It looks like you have spent a lot of time becoming knowledgeable in the
field, and that you have potential to make significant contributions to
the body of knowledge. That does not mean, however, that there are not
other points of view.