Supplement analysis backed by scientific evidence · PT

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Limited evidencePhysical performance

Creatine Ethyl Ester

Creatine ethyl ester was designed for better membrane permeability, but chemistry and clinical data both went against it: at stomach pH it degrades rapidly into inert creatinine, and the one controlled training trial found it raised muscle creatine less than monohydrate while dramatically raising serum creatinine. This is the clearest "do not buy" among creatine variants.

What the science says

  • Degrades to creatinine before it can be absorbed Limited evidence

    Stability testing across physiological pH found creatine ethyl ester is highly unstable in acidic conditions, converting largely to creatinine within minutes at gastric pH — far faster than creatine monohydrate, which is essentially stable. The ester bond intended to improve cell uptake is precisely what makes the molecule fall apart in the stomach.

  • Loaded muscle creatine worse than monohydrate in a 47-day training trial Limited evidence

    Spillane's 2009 double-blind trial gave 30 resistance-trained men monohydrate, creatine ethyl ester, or placebo (20 g/day loading, then 5 g/day) with 47 days of heavy resistance training. Monohydrate significantly increased muscle total creatine; the ethyl ester group's muscle creatine was significantly lower than monohydrate's, and CEE produced no advantage in strength, power or body composition over placebo.

  • Sharply raises serum creatinine, which can look like kidney injury on labs Limited evidence

    In the same trial, creatine ethyl ester raised serum creatinine markedly and progressively — a direct consequence of the molecule degrading into creatinine rather than delivering creatine. This is not evidence of kidney damage per se, but it confounds routine kidney function testing (eGFR) and is a practical reason to avoid the product.

Dosage & safety

Studied doseNo dose is recommended. Trials used 20 g/day for 5 days then 5 g/day for 42 days and still failed to match monohydrate. Use creatine monohydrate at 3-5 g/day instead; it is cheaper, stable, and the most extensively studied ergogenic supplement in existence.
SafetyNo serious adverse events were reported in trials, but creatine ethyl ester substantially elevates serum creatinine, which can produce a false appearance of renal impairment on blood work — tell your doctor if you have taken it before a kidney panel. GI upset is common. As with all creatine, people with kidney disease should not self-supplement. Not banned in sport. The main harm here is financial and diagnostic, not toxicological.

Scientific references

Where to buy

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