Creatine monohydrate vs HCL, ethyl ester and kre-alkalyn: what the evidence actually says
If you have spent any time looking at creatine, you will have been told that HCL absorbs better, that kre-alkalyn is pH-stable and therefore superior, and that ethyl ester is the next step up. These claims cost more to buy into. This page explains why we sell only monohydrate, and why that is not a compromise.
The authorised claim — and which form it rests on
In the UK, the only authorised health claims for creatine are:
"Creatine increases physical performance in successive bursts of short-term, high intensity exercise."
"Daily creatine consumption can enhance the effect of resistance training on muscle strength in adults over the age of 55."
These are the only claims a brand can legally make about creatine on a food supplement. They were authorised on the basis of the existing body of research. That research is overwhelmingly — almost exclusively — conducted on creatine monohydrate.
The conditions attached to those claims matter. Here they are in full:
| Claim | Daily dose | Additional conditions | Target |
|---|---|---|---|
| Physical performance in high-intensity exercise | 3g creatine | None beyond dose | Adults performing high-intensity exercise |
| Enhancing the effect of resistance training on muscle strength | 3g creatine daily | Regular resistance training, at least 3 times per week for several weeks, at 65–75% of one-rep max | Adults over 55 |
Notice that the dose is 3g. Not 5g, not a loading phase of 20g. Three grams, daily, including rest days. That is what the claim requires, and it is what the research supports.
No equivalent authorised claim exists for creatine HCL, ethyl ester or kre-alkalyn. That is not a technicality — it reflects the state of the evidence.
What HCL, ethyl ester and kre-alkalyn actually change
Each of these forms modifies creatine monohydrate in a specific way. Here is what each modification does and does not do.
Creatine HCL (hydrochloride)
Creatine bound to hydrochloric acid. The bond increases water solubility significantly — it dissolves more readily than standard monohydrate. Manufacturers argue this means you need a smaller dose for the same effect. The smaller dose claim is not supported by robust human trials. Solubility in a glass of water does not automatically translate to greater uptake into muscle tissue.
Creatine ethyl ester
An ester group is attached to the creatine molecule to theoretically improve membrane permeability and absorption. In practice, research has found that creatine ethyl ester is less stable than monohydrate and converts to creatinine (a waste product) in the gut at a higher rate. The head-to-head trials that exist do not show it outperforming monohydrate.
Kre-alkalyn (buffered creatine)
Monohydrate with an alkaline buffer added, marketed on the claim that standard creatine degrades to creatinine in stomach acid before it reaches muscle. The premise is disputed. Monohydrate is stable in the digestive tract at normal transit times. Controlled studies comparing kre-alkalyn to monohydrate have not found meaningful differences in muscle creatine saturation or performance outcomes.
Solubility is the main real difference
Strip away the marketing and the one area where these newer forms have a genuine, measurable advantage is solubility. HCL in particular dissolves more completely in water than standard monohydrate powder.
This is a real-world convenience point — standard monohydrate can leave a gritty residue at the bottom of a glass. It is not, however, a performance point.
Micronised monohydrate closes most of that gap. Micronisation reduces particle size, which improves dispersion into liquid without altering the molecule itself. Our creatine is micronised: it disperses into 150–250ml of water, juice or a shake without the gritty settle of standard monohydrate. You still get monohydrate — the form with the evidence base — in a format that mixes cleanly.
Cost comparison per gram of creatine
Prices vary by retailer and change over time, but the general pattern is consistent. These are representative figures based on widely available products at time of writing.
| Form | Typical cost per gram of creatine | Authorised claim available |
|---|---|---|
| Creatine monohydrate | 6–8p | Yes |
| Creatine HCL | 20–35p | No |
| Kre-alkalyn | 25–40p | No |
| Creatine ethyl ester | 20–30p | No |
Our micronised creatine monohydrate is 300g for £18.99. At the 3g claim dose, that is 100 days of use — 19p a day.
The premium forms cost three to five times more per gram, have no authorised claim, and have not demonstrated superior outcomes in well-controlled trials. You are paying for the chemistry of the modification, not for a better result.
Why we only sell monohydrate
We sell one form of creatine. That is a deliberate choice, not a gap in the range.
The honest reason is that monohydrate is the form the research is built on, the form the authorised claim is built on, and — once micronised — the form that addresses the only practical objection to it. Stocking HCL or kre-alkalyn would mean selling something more expensive on thinner evidence to people who have been told it is better. We are not going to do that.
If you are performing high-intensity exercise and want to meet the 3g daily dose the claim requires, monohydrate does that at 19p a day. Consistency matters more than timing, more than form, and more than whether you do a loading phase (you do not need one — it only reaches muscle saturation faster, it does not change the end point).
Take it every day, including rest days. That is the mechanism: creatine works by saturating muscle stores over time, not by being present at the moment of exercise.
- Compare powder and tablets — Same creatine, different format.
- See the full specification — Every figure, including the ones most brands leave out.
- Shop creatine — 19p a day — 300g, 100 days at the 3g claim dose. £18.99.
Do not exceed the recommended daily dose. Food supplements are not a substitute for a varied and balanced diet and a healthy lifestyle.