Here's a mail I recently received from some friends (PhDs) in the Ex Sci/Nut Biochem community. It discusses the potential dangers and (flawed marketing picture) associated with the use of Creatine Ethly Ester:
1) CEE is a true covalently bonded ester and is absorbed into blood and
tissues as the intact molecule. This is the picture that the
manufacturers would have us believe and is the basis for why they claim
CEE is superior to creatine monohydrate. However, inside cells CEE
will be unreactive with creatine kinase and may be a potential
competitive or non-competitive inhibitor to the enzyme. This would
make it toxic to brain, heart, testes, muscle and all other CK
containing tissues. People by now should be dying, but clearly are not
and this means 2) and 3) are the more likely. Nonethess, CEE should be
treated as a potentially toxic phrarmaceutical and in the US should be
treated as a drug, which requires multi species studies
to estimate LD50's and potential sites of tissue damage etc. However, recently I have been told that CEE did get new dietary ingredient status (scary).
2) CEE is hydrolysed to creatine on absorption from the gut. In this
case CEE offers no advantage over creatine monohydrate which has a
bioavilability of 100%. Indeed if hydrolysis of CEE is less than 100%
then it will be inferior to the monohydate. But in the case of
hydrolysis there are no circumstances in which it could be better than
the monohydrate in increasing tissue creatine levels. Obviously CEE
manufacturers would prefer 1) except that they then shoot themselves in
the foot over the issue of potential toxicity.
3) CEE is not a true covalently bonded ester. The whole of this is a scam
with the compound ionising in solution to free creatine, as does the
monohydrate and all salts of creatine. In this case CEE would again
represent no advantage over creatine monohydrate, except to the seller
who can double the price.
The failure of the US sports nutrition community (industry and the
universities) to call for closer examination of CEE seriously questions its
credibility in the eyes of many scientist in this country and the world. A simple water solvation test would answer 3), i.e. whether or not it was a covalent or ionisable derivative of creatine. The work time would be about one hour. Investigation of whether CEE is a competitive or non-competitive inhibitor of creatine kinase would take 2-3 hours. If either of these occured then clearly CEE must be investigated in at least two species to investigate lethality and potential organ damage. If on the other hand CEE is ionisable then I see no reason why a bioavailability study should not be undertaken comparing this, on a molar/molar basis, with
creatine monohydrate. My guess is that plasma AUC would be identical.
Again a very simple study.
None of this is rocket science but could spare a few lives, if the
manufacturers claims on the absorption of CEE are to believed.
That quote came from a member @ Precision Nutrition. This next one I quoted from John Berardi himself.
While you might not "feel" bad, there might be some not-so-good biochemical stuff going on. With this risk to benefit, I'd just switch over to plain micronized creatine monohydrate.
What do you think of EAS's Phosphagen? Good?
I don't like to answer questions about individual products as that invites a billion questions...after all, there are over 60,000 products on the market.
However, I will say this...most MICRONIZED creatine monohydrate products work just fine.
If CEE is out, what is your view on other creatines, including creatine gluconate (currently available as bulk powder and in gaspari sizeon)?
Im a fan of plain creatine monohydrate (micronized). I don't see the point in many of the other creatines.