Creatine: the best-evidenced supplement there is
What it does, what dose, why monohydrate beats every expensive form, and what is true about hair, kidneys and water retention.
If you are only ever going to buy one supplement, this is it. It is the most studied, it has the largest effect on strength and muscle mass, it is the cheapest on the list, and it has the best safety record after more than thirty years of literature.
What it actually does
Muscle powers contraction with ATP, and its store lasts a few seconds. Phosphocreatine is the reservoir that regenerates that ATP immediately. Supplementing creatine fills that reservoir beyond what diet achieves, by roughly 20-40%.
The practical consequence is not "more strength" directly: it is one or two more repetitions on the last sets, session after session. That extra volume accumulated over months is what turns into muscle. Creatine does not build: it lets you train slightly more (why volume rules).
It increases lean mass and strength consistently
The ISSN position stand is among the most emphatic in the supplement literature: creatine monohydrate is the most effective ergogenic aid available for increasing high-intensity work capacity and lean mass. Branch’s meta-analysis quantifies the effect at around 1-2 kg more lean mass and 5-15% improvements in strength and power versus placebo across 4-12 week programmes.
Dose: with or without loading
There are two protocols and they arrive at the same place. The only difference is how long they take.
| Protocol | How | Stores full in | Downside |
|---|---|---|---|
| With loading | 0.3 g/kg/day (about 20 g) in 4 servings for 5-7 days; then 3-5 g | ~1 week | GI discomfort is common with the large servings |
| Without loading | 3-5 g a day from day one | 3-4 weeks | None, other than the wait |
The default recommendation: no loading
3-5 g a day, every day, rest days included. Loading only pays off if you have a competition or a demanding block in under three weeks. And there is no need to cycle: there is no evidence that periodically stopping does anything.
- Maintenance dose
- 3-5 g/day
- Timing
- Irrelevant
- What to take it with
- Water, a shake, juice or food
- How long until you notice
- 2-4 weeks
Very large or very lean-massive people, up to 5-10 g.
The difference between before and after training is marginal in the literature. What matters is not skipping it.
Uptake is slightly better with carbohydrate and protein; it is not decisive.
Weight first (intracellular water), repetitions after.
Monohydrate versus every other form
No alternative form has beaten monohydrate
The ISSN is blunt: monohydrate is the most studied and effective form, and none of the commercial variants has been shown to be superior. Jagim’s trial compared a buffered creatine (Kre-Alkalyn type) against monohydrate over 28 days of training: no differences in muscle creatine, body composition or adaptations. Ethyl ester degrades to creatinine before reaching muscle — that is, it works worse.
- Monohydrate: the standard. If it is also Creapure, that is a German purity mark with published analyses; it costs slightly more.
- Micronised: monohydrate ground finer. Dissolves better. Same product, same effect.
- HCl, buffered, ethyl ester, liquid, gummies: more expensive per gram of creatine, with no demonstrated advantage. Liquid also degrades in solution.
The one legitimate reason to pay for another form
That monohydrate genuinely upsets your stomach at low doses. It is uncommon and usually resolves by taking 3 g instead of 5, split and with food.
The worries, one by one
It does not damage the kidneys in healthy people
This is the most repeated confusion: creatine raises blood creatinine, which is the marker used to estimate kidney function. The value rises because there is more substrate, not because the kidney is working worse. Long follow-up studies — up to five years — in healthy people find no decline in renal function. With pre-existing kidney disease, the decision belongs to a doctor, not a tub.
- Does it cause baldness? A single 2009 study in rugby players found an increase in dihydrotestosterone with high loading. It has never been replicated, and it did not measure hair loss. There is no basis for the claim.
- Does it retain water? Yes, inside the muscle cell. That is part of the mechanism, not a side effect, and it is not subcutaneous bloating. It shows up as 1-2 kg of weight in the first weeks.
- Does it dehydrate or cause cramps? The evidence points the other way: if anything, it improves heat tolerance.
- Do you need to take breaks? No. Cycling adds nothing and only empties the stores.
- Is it a steroid? No. It is a compound already present in meat and fish that the body makes from three amino acids.
Cases where it works especially well
Vegetarians, women and older adults gain the most
Vegetarians start from lower muscle stores — dietary creatine comes from meat and fish — and tend to show larger responses. In women, Smith-Ryan’s review describes lower baseline stores and benefits for strength and body composition, without the disproportionate weight gain people fear. In over-60s, combined with resistance training, it improves muscle mass and markers of physical function, which makes it a tool against sarcopenia (why it matters past 40).
Creatine and running
In distance running it does not improve performance and adds 1-2 kg of weight, which costs you. Where it does fit is the runner’s strength work and short efforts — track, hills, the final kilometre (strength for runners). For a marathoner in race week it is not the best buy; for a middle-distance runner it is.
There is also a growing line on cognitive function: Forbes’ review describes improvements in memory and in cognitive tasks under sleep deprivation, with clearer effects in vegetarians and older adults. The evidence is still being built, but it suggests muscle is not the only tissue that uses the store.
What to check when buying creatine
It is the product that needs the least thought and where people most often overpay.
- That it says "monohydrate"Any other form is more expensive with no demonstrated advantage.
- Creapure if it is availableA purity mark with published analyses; usually costs only slightly more.
- Unflavoured and unmixedTubs of "creatine + 7 ingredients" hide how much creatine is actually in there.
- Price per gram of creatineA reasonable benchmark: under €0.05 per gram in 500 g or 1 kg formats.
- A batch-tested mark if you competeCreatine is one of the cleanest categories, but the liability is still yours.
Takeaways
- 3-5 g of monohydrate a day, every day, no cycling. Loading only speeds up the start.
- No expensive form has beaten monohydrate in a controlled trial.
- The rise in blood creatinine is not kidney damage; the extra weight is intracellular water.
- Vegetarians, women and over-60s gain the most.
- In pure endurance it adds little; in strength and short efforts it is the best thing available.
Sources for this chapter
- [1]Kreider RB, Kalman DS, Antonio J, et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition. position stand
- [2]Antonio J, Candow DG, Forbes SC, et al. (2021). Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?. Journal of the International Society of Sports Nutrition. review
- [3]Branch JD (2003). Effect of creatine supplementation on body composition and performance: a meta-analysis. International Journal of Sport Nutrition and Exercise Metabolism. meta-analysis
- [4]Jagim AR, Oliver JM, Sanchez A, et al. (2012). A buffered form of creatine does not promote greater changes in muscle creatine content, body composition, or training adaptations than creatine monohydrate. Journal of the International Society of Sports Nutrition. trial
- [5]Smith-Ryan AE, Cabre HE, Eckerson JM, Candow DG (2021). Creatine Supplementation in Women's Health: A Lifespan Perspective. Nutrients. review
- [6]Candow DG, Forbes SC, Chilibeck PD, Cornish SM, Antonio J, Kreider RB (2019). Effectiveness of Creatine Supplementation on Aging Muscle and Bone: Focus on Falls Prevention and Inflammation. Journal of Clinical Medicine. review
- [7]Forbes SC, Cordingley DM, Cornish SM, et al. (2022). Effects of Creatine Supplementation on Brain Function and Health. Nutrients. review
- [8]Australian Institute of Sport (2025). AIS Sports Supplement Framework: clasificación ABCD de suplementos. Australian Institute of Sport. official guideline