Ingredient Reference
Creatine Monohydrate: Chemistry, Forms, Studied Amounts and Safety
What creatine is, where it comes from, how to read a creatine label, what amounts human studies used, and who should ask a clinician first.
Join the WaitlistCreatine on the Label
What our creatine product holds, taken from its product page.
How to use it (product page): mix 1 scoop (5 g) daily, or as directed on the label, into water, juice or a smoothie. Each 150 g jar holds 30 scoops. For adults 18 and over. Not on sale yet; join the waitlist on the product page to hear when it launches. Label math: creatine monohydrate is about 88% creatine by weight, so a 5 g scoop supplies roughly 4.4 g of creatine itself, by our arithmetic.
Creatine at a Glance
| Item | Details |
|---|---|
| Names | Creatine; N-amidinosarcosine. Supplement form: creatine monohydrate, CAS 6020-87-7. |
| Formula | Creatine C4H9N3O2. The monohydrate adds one water molecule: 149.1 g/mol, 12.1% water. |
| Made in the body | About 1 g daily in the liver and kidneys, from glycine, arginine and methionine. |
| Food sources | About 2 g per pound of beef or salmon, 2.3 g per pound of pork. |
| Stored | About 95% in skeletal muscle; roughly 120 g in a 70 kg adult. |
| Amounts in studies | 3 to 5 g daily ongoing; 20 g daily for 5 to 7 days when loading. |
| Main cautions | Kidney disease, kidney-affecting medicines, pregnancy, breastfeeding, under 18, kidney blood tests. |
| US status | Dietary supplement ingredient; FDA GRAS notice GRN 931 covers one supplier's use in certain foods. |
Here for focus and memory? The brain research is covered in Creatine for Brain Health: Benefits, Dose and What Studies Show. This page sticks to reference facts.
Chemistry, Synthesis and Storage
Creatine is a small nitrogen-rich molecule. Its chemical name, N-(aminoiminomethyl)-N-methylglycine, describes it: sarcosine (N-methylglycine) carrying an amidino group.
How the body builds it
Two enzyme steps, mainly in the kidneys and liver. AGAT (arginine:glycine amidinotransferase) joins part of arginine to glycine, forming guanidinoacetate. GAMT (guanidinoacetate methyltransferase) then adds a methyl group from S-adenosylmethionine, made from methionine.
Storage and turnover
Muscle holds creatine partly as phosphocreatine, a phosphate reserve that creatine kinase uses to recharge ATP. Average stores are about 120 mmol per kg of dry muscle, with a ceiling near 160; vegetarians have been reported at 90 to 110. About 1 to 2% of muscle creatine becomes creatinine each day and leaves in urine, so the body replaces 1 to 3 g daily, roughly half from food.
Forms and How to Read a Label
| Form | What it is | What to know |
|---|---|---|
| Creatine monohydrate | Creatine crystallized with one water molecule | The form in nearly all research. 1 g of creatine equals 1.12 g of monohydrate. |
| Creatine ethyl ester | Creatine bonded to an ethyl group | Converted largely to creatinine in testing; raised serum creatinine in one study. |
| Citrate, pyruvate, malate and other newer forms | Creatine paired with another acid, or buffered | A 2011 review found little to no evidence of better uptake, effect or safety than monohydrate. |
How it is made
The creatine monohydrate in GRAS notice GRN 931 is made by chemical synthesis from cyanamide and sodium sarcosinate, with a structure identical to creatine in vertebrates. That supplier specified at least 99.9% purity and limits for creatinine (100 mg/kg), dicyandiamide (50 mg/kg) and dihydrotriazine (3 mg/kg).
Mixing, solubility and storage
Monohydrate dissolves at about 14 g per liter at 20 °C and 6 g per liter at 4 °C, so fully dissolving 5 g takes roughly 360 ml of room temperature water; in less liquid some stays suspended. Stored dry, the powder stayed stable for over 3 years at 40 °C. In solution it slowly forms creatinine: after 3 days at 25 °C, about 4% at pH 5.5, 12% at pH 4.5 and 21% at pH 3.5. Mix and drink it the same day.
What to check on a label
- The form: "creatine monohydrate", not just "creatine" or a blend name.
- Grams per serving, and how many scoops or capsules make it.
- Other ingredients, such as sweeteners or sugars in gummies and drinks.
- Ingredient testing for purity and the impurities above.
Format trade-offs: Creatine Powder vs Pills vs Gummies: Which Form Is Best?
Creatine in Human Studies
Selected human trials and reviews; all used creatine monohydrate.
| Study | Who | Amount a day | Length | Measured | Result |
|---|---|---|---|---|---|
| Hultman 1996, J Appl Physiol | 31 men | 20 g; or 3 g | 6 days; 28 days | Muscle creatine by biopsy, urinary creatinine | About 20% rise either way, faster with 20 g; 2 g daily held it; without that, baseline within about 30 days |
| Powers 2003, J Athl Train | 16 men, 16 women, resistance trained | 25 g, then 5 g | 7 days, then 21 | Muscle creatine, body mass, body water compartments | Body mass, total body water and muscle creatine rose; water distribution unchanged |
| Dechent 1999, Am J Physiol | 6 healthy young adults | 20 g | 4 weeks | Brain creatine by MR spectroscopy | Average rise 8.7%, from 4.7% in gray matter to 14.6% in the thalamus; reversed 3 months or more after stopping |
| Rae 2003, Proc Biol Sci | 45 young vegetarians, crossover | 5 g | 6 weeks | Backward digit span, Raven's matrices | Higher scores on both |
| Benton 2011, Br J Nutr | 128 young women | 20 g | 5 days | Memory, reaction time | Better memory in vegetarians than meat eaters on creatine; steadier reaction times in both |
| Ostojic 2008, Res Sports Med | 59 male soccer players | 10 g once, or 2 x 5 g | 28 days | Digestive complaints | Diarrhea 55.6% with one 10 g serving, 28.6% with two 5 g; split similar to placebo |
| Chilibeck 2017, meta-analysis | 22 trials, 721 adults, mean ages 57 to 70, strength training | Varied | 7 to 52 weeks | Lean mass, chest and leg press | About 1.37 kg more lean tissue than placebo; greater press gains |
| Lak 2025, J Int Soc Sports Nutr | 45 trained men aged 18 to 40 | 5 g | 12 weeks | DHT, testosterone, hair density and thickness | No group differences in DHT or any hair measure |
Studied Amounts by Purpose
Amounts from research and reference sources, not directions. Follow your product's label.
| Setting | Amount |
|---|---|
| Fast loading | Four 5 g servings daily (about 0.3 g per kg) over 5 to 7 days |
| Ongoing intake | 3 to 5 g daily; 2 g daily held raised levels for 30 days in one trial |
| No loading | 3 g daily for 28 days; reference range 3 to 6 g daily for 3 to 4 weeks |
| Brain imaging study | 20 g daily for 4 weeks |
| Long-term safety review | Intakes as high as 30 g daily, for as long as 5 years |
| Fortified foods (GRN 931) | 1.12 g monohydrate (1 g creatine) per serving |
Dosing by goal and body weight: how much creatine per day.
Safety and Who Should Ask First
The 2017 International Society of Sports Nutrition (ISSN) position stand found no compelling evidence of harm from creatine monohydrate at intakes as high as 30 g daily for as long as 5 years, in healthy and clinical groups, and named weight gain as the only consistently reported side effect. The NIH Office of Dietary Supplements calls short-term use safe for healthy adults.
- Body weight: mostly water in muscle; one strength training study measured 1 to 2 kg in a month.
- Digestive upset: more common with single large servings than split ones.
- Anecdotal reports: nausea, cramps, heat intolerance and muscle stiffness; adequate fluid may help.
Weight, bloating, hair and kidney questions: Creatine Side Effects: Weight Gain, Bloating, Acne and Is It Safe?
Kidney blood tests
Creatine turns into creatinine, the marker many kidney function tests rely on, and urinary creatinine rose during loading in the Hultman trial. Tell whoever orders your blood work that you take creatine.
Who should ask a clinician first
Anyone with kidney disease or reduced kidney function, anyone on medicine that affects the kidneys, people who are pregnant or breastfeeding, anyone under 18, and anyone with a chronic condition or on prescription medicine.
Regulatory Status in the US
Creatine monohydrate is sold as a dietary supplement ingredient under the Dietary Supplement Health and Education Act of 1994 (DSHEA). FDA does not approve supplements before sale; the maker is responsible for safety and labeling, and structure and function statements carry the disclaimer at the bottom of this page.
For conventional foods, AlzChem notified FDA that its creatine monohydrate is generally recognized as safe (GRAS) in energy drinks, protein bars and powders, milkshakes, meal replacements, meat analogues and dry drink mixes at 1.12 g per serving. In GRN 931 (letter of November 12, 2020, corrected December 3, 2020) FDA said it had no questions. FDA notes such a letter is not an affirmation of GRAS status.
A 2011 review reported that FDA had objected to most notifications it received for newer creatine forms.
Creatine FAQ
How much actual creatine is in 5 g of creatine monohydrate?
About 4.4 g. Creatine monohydrate is roughly 88 percent creatine and 12 percent water of crystallization by weight, so 1 g of creatine equals 1.12 g of the monohydrate.
What is supplemental creatine made from?
The creatine monohydrate described in FDA GRAS notice GRN 931 is made by chemical synthesis from cyanamide and sodium sarcosinate. Its structure is identical to the creatine the body makes and that meat and fish contain.
How much creatine does the body make, and how much comes from food?
The liver and kidneys make about 1 g a day. The body replaces about 1 to 3 g daily in total, roughly half from food; a pound of beef or salmon has about 2 g.
Does creatine break down once it is mixed into a drink?
Yes, slowly. In water it converts to creatinine, faster in acidic and warm liquids: after 3 days at 25 C, about 4 percent at pH 5.5 and 21 percent at pH 3.5. Dry powder stayed stable for over 3 years.
Is creatine monohydrate GRAS?
FDA had no questions about one supplier's GRAS conclusion for creatine monohydrate in certain foods at 1.12 g per serving (GRN 931, 2020). In supplements it is sold as a dietary ingredient under DSHEA.
Why can creatine change a kidney blood test?
Creatine turns into creatinine, the marker many kidney function tests use, so taking it can raise creatinine on a test. Tell whoever orders your labs that you take it.
More on Creatine
Our guides
More creatine reading
Sources
- Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr, 2017. PubMed 28615996
- NIH Office of Dietary Supplements. Dietary Supplements for Exercise and Athletic Performance: Fact Sheet for Health Professionals. ods.od.nih.gov
- AlzChem Trostberg GmbH. GRAS Notice GRN 931: Creatine monohydrate. 2020. fda.gov
- US Food and Drug Administration. Response letter, GRAS Notice GRN 000931. December 3, 2020. fda.gov
- US Food and Drug Administration. Questions and Answers on Dietary Supplements. fda.gov
- Jäger R, et al. Analysis of the efficacy, safety, and regulatory status of novel forms of creatine. Amino Acids, 2011. DOI 10.1007/s00726-011-0874-6
- Hultman E, et al. Muscle creatine loading in men. J Appl Physiol, 1996. PubMed 8828669
- Powers ME, et al. Creatine supplementation increases total body water without altering fluid distribution. J Athl Train, 2003. PubMed 12937471
- Dechent P, et al. Increase of total creatine in human brain after oral supplementation of creatine-monohydrate. Am J Physiol, 1999. PubMed 10484486
- Rae C, et al. Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial. Proc Biol Sci, 2003. PubMed 14561278
- Benton D, Donohoe R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br J Nutr, 2011. DOI 10.1017/S0007114510004733
- Ostojic SM, Ahmetovic Z. Gastrointestinal distress after creatine supplementation in athletes: are side effects dose dependent? Res Sports Med, 2008. PubMed 18373286
- Chilibeck PD, et al. Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a meta-analysis. Open Access J Sports Med, 2017. DOI 10.2147/OAJSM.S123529
- Lak M, et al. Does creatine cause hair loss? A 12-week randomized controlled trial. J Int Soc Sports Nutr, 2025. PubMed 40265319
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Ask your clinician before starting creatine if you have kidney concerns, are pregnant or breastfeeding, are under 18, or take prescription medicine.