Creatine

Also known as: Creatine monohydrate, Methylguanidinoacetic acid

A compound made from amino acids that fuels short bursts of muscle power and is the most studied sports supplement in the world.

Editorial review by the IngredientWiki Editorial Team
Updated 2026-09-26
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Fine white creatine-like powder with a compact measuring scoop — Editorial illustration

Creatine monohydrate is one of the better-supported sports supplements for repeated high-intensity performance, strength, and lean-mass gains when paired with training. Cognitive evidence is promising but more heterogeneous, and results for monohydrate should not be assigned automatically to proprietary forms.^{1, 2}

Stored in muscle as phosphocreatine, which rapidly regenerates ATP^{1, 2}
Also found in red meat and fish; the body makes about 1 g per day^{1, 2}
Standard dose: 3–5 g of creatine monohydrate daily^{1, 2}
Weight gain of 1–3 lb is common and is mostly water in muscle^{1, 2}

What is Creatine?

Creatine is one of the most heavily researched dietary supplements in existence, with thousands of studies spanning more than 30 years. Roughly 95% of the body's creatine is stored in skeletal muscle, where it acts as an energy buffer: by donating a phosphate group to ADP, phosphocreatine regenerates ATP faster than other pathways can, powering maximal efforts lasting up to about 10–15 seconds. Vegetarians and vegans tend to have lower muscle creatine stores and often see the largest responses to supplementation.^{1, 2}

Where it comes from

Natural sources

Made in the liver, kidneys, and pancreas from arginine, glycine, and methionine
Red meat and poultry (about 1–2 g per pound of raw meat)
Fish such as herring and salmon

How it's made

Supplemental creatine monohydrate is produced synthetically from sarcosine and cyanamide.

What it does in products

Benefits

Strength and power gains

strong evidence

Meta-analyses of hundreds of trials consistently show creatine plus resistance training increases maximal strength and power output more than training alone, across ages and sexes.^{1, 2, 3}

The benefit is most consistent for repeated high-intensity work performed alongside resistance training; it is not a universal endurance enhancer.

Lean mass gains

strong evidence

By allowing more training volume, creatine supports greater muscle accretion. Typical gains over 4–12 weeks are 2–5 lb, with an initial 1–3 lb from intramuscular water.^{2, 3}

Meta-analyses support a modest increase in lean mass with resistance training; early water retention contributes to scale and lean-mass changes.

High-intensity performance

strong evidence

Creatine improves repeated sprint and high-intensity interval performance, particularly in efforts lasting seconds rather than endurance events.^{1, 2}

Evidence is strongest for short, repeated, high-intensity exercise and creatine monohydrate, not every sport or proprietary creatine form.

Brain health and cognition

moderate evidence

The brain also uses creatine. Early research suggests supplementation may blunt mental fatigue during sleep deprivation and is being studied in concussion recovery and aging populations.⁴

Meta-analysis suggests possible memory and cognition effects, with greater uncertainty by age, diet, sleep status, and cognitive outcome.

Evidence scope and limitations

The review centers on creatine monohydrate in adults, especially when combined with resistance or repeated high-intensity exercise; cognitive evidence is evaluated separately.

Findings for creatine monohydrate should not be transferred automatically to buffered, esterified, or proprietary forms.
Sports outcomes depend on training status and task; cognitive findings remain more heterogeneous than performance findings.

Evidence last checked: 2026-09-26

Side effects & safety

Water retention and weight gain (common)Expected and usually desired; reflects creatine working in muscle cells.

Digestive upset with large single doses (uncommon)Splitting doses or skipping the loading phase prevents cramping and diarrhea.

Muscle cramps (rare)Older anecdotal reports; controlled trials do not show increased cramping with adequate hydration.

Safety considerations

Creatine has not been studied in pregnancy; standard guidance is to avoid use during pregnancy and breastfeeding out of caution.
Creatine increases muscle water content; staying hydrated is important, especially in heat.
Kidney function tests may show elevated creatinine, which is a normal artifact of supplementation, not kidney damage.
Not for: Pre-existing kidney disease (use only under medical supervision)

^{1, 2}

Amounts studied & product use

These figures describe research or common product use, not a personal dose or treatment recommendation.

In supplement studies and products

Most sports studies use creatine monohydrate at 3–5 g daily. Some trials begin with roughly 20 g daily in divided amounts for 5–7 days, but loading is a research protocol rather than a requirement and other creatine forms cannot assume the same evidence.

^{1, 2}

Regulatory status

Dietary supplement regulated by the FDA under DSHEA. Creatine monohydrate has a long safety record and is permitted in international sport, including by the World Anti-Doping Agency.
GRAS (generally recognized as safe) for food use.

⁵

Creatine monohydrate vs other forms

Dozens of creatine variants — hydrochloride, ethyl ester, buffered creatine, creatine nitrate — are marketed as superior. The evidence does not support these claims: creatine monohydrate remains the most studied form and outperforms or matches all alternatives at a fraction of the cost. Any form must raise muscle phosphocreatine stores to work, and monohydrate does this effectively with excellent tolerance.

^{1, 2}

Frequently asked questions

Do I need to load creatine?

No. Loading (20 g daily for 5–7 days) saturates muscles faster, but taking 3–5 g daily reaches the same saturation in about three to four weeks with fewer stomach issues. For most people, the daily dose is simpler and equally effective in the long run.^{1, 2}

Does creatine cause hair loss?

The concern traces to a single small study from 2009 that found creatine raised DHT levels, a hormone linked to male-pattern baldness. No study has ever shown creatine causes hair loss, and the DHT finding has not been replicated. Genetics remain the main predictor.^{1, 2}

Is creatine only for men and bodybuilders?

No. Creatine benefits women, older adults, and team-sport athletes equally, and it is increasingly studied for muscle preservation during aging and recovery from disuse. Dosing does not differ by sex.^{1, 2}

The bottom line

Creatine monohydrate has strong performance evidence and a substantial safety record in healthy adults. Its clearest value is training-related; cognitive claims are less settled.

References

Dietary Supplements for Exercise and Athletic Performance: Health Professional Fact Sheet. NIH Office of Dietary Supplements (2025) · government guidance
International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation. Journal of the International Society of Sports Nutrition (2017) · clinical guideline · PMCID PMC5469049
Creatine supplementation and resistance-training changes in body composition: a systematic review and meta-analysis. Journal of Strength and Conditioning Research (2024) · meta analysis · PMID 39074168
Effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis. Frontiers in Nutrition (2024) · meta analysis · PMID 39070254
Dietary Supplements. U.S. Food and Drug Administration (2025) · government guidance

Revision history

2026-09-26Replaced search-result citations with exact sources, mapped claims to evidence, and reassessed evidence strength.