Creatine monohydrate is the rare supplement that earns its hype. Hundreds of trials, a formal position stand from the International Society of Sports Nutrition, and a pile of meta-analyses all land in roughly the same place: it works for muscle, it is cheap, and it is one of the best-tolerated compounds you can put in a shaker. The catch is that the same fame has attracted a circus of myths, from kidney damage to baldness to "it is basically a steroid." Almost none of it survives contact with the research.
This is a research-backed look at what the evidence shows, not a first-hand trial. The Catalyst Feed has not run lab tests on anyone. What we have done is read the position stands and meta-analyses and sort the findings into three honest tiers: rock-solid, plausible-but-emerging, and noise. Here is where the line sits.
What creatine actually is
Creatine is a naturally occurring compound, a non-protein amino acid in the guanidine phosphagen family, and you already eat it. It turns up mostly in red meat and seafood, and your own body makes about 1 g a day in the liver, kidneys and pancreas from the amino acids glycine, arginine and methionine. Total body stores sit around 120 g, roughly 95 percent of it parked in skeletal muscle and the remaining 5 percent spread across the brain, liver, kidney and testes (Perspective: Creatine, a conditionally essential nutrient, PMC).
Inside muscle, creatine becomes phosphocreatine, which acts as a rapid-fire battery. During short, intense efforts, a heavy set, a sprint, a jump, phosphocreatine donates a phosphate to regenerate ATP, the molecule your cells spend for energy. More phosphocreatine in the tank means you can sustain those maximal efforts for a beat longer before fatigue bites. That is the entire mechanism, and it explains exactly what creatine is good at and what it is not.
Tier 1: the settled science
This is the part that is no longer up for debate. The ISSN position stand calls creatine monohydrate "the most effective ergogenic nutritional supplement currently available to athletes" for raising high-intensity exercise capacity and lean mass during training. After loading, performance of high-intensity or repetitive exercise generally improves by 10 to 20 percent (Kreider et al., 2017, JISSN). That is a strong claim for a supplement, and it is backed by the depth of the literature rather than one flashy study.
The body-composition picture is just as clear. A 2024 meta-analysis of randomised controlled trials found that adding creatine to resistance training produced roughly 1.1 kg more lean body mass, plus a modest drop in fat mass, compared with resistance training alone, across all training-experience levels (Nutrients, 2024). Note the structure of that finding: creatine plus training, not creatine on the sofa. It is a multiplier on the work you already do, not a substitute for it.
It also is not a young-bloke-only thing. A systematic review and meta-analysis in older adults found that creatine combined with resistance training significantly improved lower-limb strength and lean tissue mass versus training alone (PMC, 2021). Given how central muscle and lower-body strength are to ageing well, that is arguably the most underrated line in the whole creatine file.
The honest headline
Tier 2: plausible, but still early
Here is where the recent excitement lives, and where the honest move is to stay calm. The brain holds creatine too, and the energy-buffering logic that works in muscle could plausibly help neurons under stress. The data are promising but the certainty is moderate at best.
A 2024 systematic review and meta-analysis pooling 16 trials and 492 participants found a significant positive effect on memory, with small effects on processing speed and attention time. It found no significant effect on overall cognition or executive function, and the authors rated the certainty as moderate for memory and low for the rest (Frontiers in Nutrition, 2024). So: a real signal for memory, not a blanket "creatine makes you smarter."
The sharper finding sits in the stress context. Randomised crossover trials show that a single high dose can blunt the cognitive decline, on logical and numerical tasks, processing speed and vigilance, that comes with sleep deprivation, alongside measurable shifts in the brain's high-energy phosphates (PMC, 2023). That fits the energy-demand story neatly: the brain benefit shows up most when the brain is energetically taxed. Regulators are watching this space too, with the EFSA having evaluated a health claim on creatine and cognitive function (PMC). Taken seriously, yes. Settled, no.
Recovery is the other "maybe," and it is genuinely mixed. One systematic review and meta-analysis concluded creatine does not accelerate recovery from exercise-induced muscle damage, while the same body of work shows it does help replenish muscle glycogen alongside carbohydrate after exhausting exercise (PubMed, 2021). So if you have heard creatine cures soreness, temper that. The glycogen angle is the more defensible recovery benefit.
Tier 3: the myths that refuse to die
Now the slander, investigated and largely dismissed.
- "It wrecks your kidneys." A 2025 systematic review and meta-analysis of 21 studies found creatine causes only a modest, expected rise in serum creatinine, a normal metabolic by-product, not a damage marker, and no significant change in glomerular filtration rate. The conclusion: it is likely safe for kidney function in healthy people and across various clinical populations (BMC Nephrology, 2025). The ISSN agrees, finding no compelling evidence of harm to renal function and reporting that intake of up to 30 g a day for five years has been safe and well tolerated (Kreider et al., 2017). The creatinine confusion is the whole trick: a blood marker nudges up, a panicked headline follows, and the kidneys are fine.
- "It is a steroid." No. Creatine has a completely different chemical structure, is regulated as a dietary supplement under DSHEA, and is not a controlled substance (Antonio et al., 2021, JISSN). The same review found no evidence that creatine raises total testosterone, free testosterone or DHT.
- "It causes hair loss." This scare traces to a single 2009 study showing a DHT rise that stayed within normal clinical limits, and it has never been replicated. The current evidence does not link creatine to hair loss or baldness (Antonio et al., 2021).
- "It makes you bloated and fat." Creatine does not add fat mass. Early weight gain is water drawn into muscle cells, intracellular water, not subcutaneous puffiness, with one study noting roughly a 9 percent rise in intracellular water (Antonio et al., 2021).
- "It dehydrates you and causes cramps." The opposite, if anything. Collegiate American-football players on creatine had significantly less cramping, heat illness and dehydration than non-users (Antonio et al., 2021).
What the research uses, and who responds most
A note on protocols, framed as description rather than instruction. The studies that report a loading phase typically use a higher short-term intake followed by a lower maintenance amount, but loading is optional: research shows that around 3 to 5 g a day for about 28 days reaches the same muscle saturation as a faster high-dose load (Antonio et al., 2021). Plain monohydrate is the form with the evidence behind it; the pricier "advanced" versions mostly buy you a bigger bill.
One group tends to respond more. Vegetarians and vegans start with lower baseline creatine stores, because the dietary supply comes from meat and fish, so they often show a larger absolute jump in stores after supplementing, and in some studies a greater cognitive response. If you eat little or no animal protein, you are likely starting from further back, which can mean a more noticeable shift.
This is informational coverage, not medical advice. The reassuring kidney data apply to healthy people and the clinical populations studied, not to everyone. Anyone with existing kidney disease, anyone pregnant or breastfeeding, and anyone on medication should talk to a doctor before starting creatine or any supplement. The point here is to separate what the science shows from what the forums shout, not to write you a protocol.
Sources
- ISSN position stand: safety and efficacy of creatine supplementation (Kreider et al., 2017, JISSN)
- Common questions and misconceptions about creatine (Antonio et al., 2021, JISSN)
- Creatine and resistance training on muscle strength in adults under 50 (Nutrients, 2024)
- Creatine ingestion strategies, lean tissue and strength in older adults (PMC, 2021)
- Creatine and cognitive function: systematic review and meta-analysis (Frontiers in Nutrition, 2024)
- Single-dose creatine and cognition during sleep deprivation (PMC, 2023)
- Creatine and kidney function: systematic review and meta-analysis (BMC Nephrology, 2025)
- Creatine and markers of exercise-induced muscle damage (PubMed, 2021)
- Perspective: Creatine, a conditionally essential nutrient (PMC)
- EFSA evaluation of creatine and cognitive function (PMC)
