Is Creatine Safe? What 685 Trials Found
What the research says about kidneys, cramps, hair, weight and caffeine. Plus how to take creatine with confidence.
13.7% vs 13.2%
Creatine groups versus placebo groups [2].
Is creatine bad for your kidneys?
In healthy people, no. Creatinine is a breakdown product of creatine and the marker most kidney blood tests use. This is what the research shows [3].
Kidney filtration measured directly
No significant difference
Compared with placebo, using a tracer test (p = 0.06).
Blood creatinine (the standard test)
0.14 mg/dL higher
than usual. That can make a standard kidney result look worse than your kidneys really are.
"These findings likely reflect altered creatinine metabolism rather than kidney injury"
de Souza Almeida et al. (2026), International Urology and Nephrology, published online ahead of print [3]
Before a blood test, tell your doctor you take creatine so they can read the result in context.
Common worries, answered
Cramps and heat
A review of 10 randomised trials found no evidence creatine affects heat loss or fluid balance in the heat. Cramping was rare [10][2].
Hair loss
In a 2025 trial, 12 weeks at 5g a day made no difference to the hormone that drives hair loss (DHT) or to eight hair measures [12].
Weight gain
It can increase weight but it's mostly water and lean tissue. Across 143 trials, fat mass did not change significantly [4].
Upset stomach
People with sensitive stomachs can split smaller doses too. Two 5g doses were no different from placebo [16].
Other considerations
As with any supplement, check with your doctor first if any of these apply. This is mostly because the trials haven't included these groups yet, not because harm has been shown.
You have kidney disease or one kidney
Trials in people with kidney disease are few and small [17].
You're pregnant or breastfeeding
Not enough research has been done on creatine's safety in pregnancy [14].
You're under 18
The International Society of Sports Nutrition supports use only with supervised training and recommended doses [1].
You take medication that can affect the kidneys
One review flagged a possible higher risk of kidney problems [18].
You have bipolar disorder
Two small studies reported mood switches in 4 people. Studies this small can't show creatine caused them [19][20].
You're due for a kidney blood test
Tell your doctor you take creatine so they can read the result in context [3].
How to take creatine
3 to 5g of creatine monohydrate a day, every day [1]. Taking it every day matters more than the time of day.
Taken daily, it fills muscle stores over about three to four weeks [1]. Loading is optional. If you compete in a weight class, skip loading in the week before a weigh in [8][5].
Sour Peach Creatine Gummies
One gummy provides 1.25g of creatine monohydrate. Four gummies provide 5g, the daily dose used in research. The labelled serve on the bag is one gummy because Australian food labelling rules cap a labelled serve at 3g of creatine. Every flavour has the same creatine content. Lab tested by Eurofins.
Shop Sour Peach
Our methodology
We searched PubMed in October 2026 and cite 19 papers and one guidance page. A second researcher rechecked every figure against the papers. Some researchers cited have links to supplement companies.
References
All 20 references, each with DOI and PubMed links
- 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, 14, 18. doi.org/10.1186/s12970-017-0173-z (PubMed: pubmed.ncbi.nlm.nih.gov/28615996/)
- Kreider RB, Gonzalez DE, Hines K, et al. (2025). Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports. Journal of the International Society of Sports Nutrition, 22(sup1), 2488937. doi.org/10.1080/15502783.2025.2488937 (PubMed: pubmed.ncbi.nlm.nih.gov/40198156/)
- de Souza Almeida A, da Silva LOD, Takahasi BNA, et al. (2026). Impact of creatine supplementation on kidney health: a systematic review and meta-analysis. International Urology and Nephrology, online ahead of print. doi.org/10.1007/s11255-026-05287-x (PubMed: pubmed.ncbi.nlm.nih.gov/42507286/)
- Pashayee-Khamene F, Heidari Z, et al. (2024). Creatine supplementation protocols with or without training interventions on body composition: a GRADE-assessed systematic review and dose-response meta-analysis. Journal of the International Society of Sports Nutrition, 21(1), 2380058. doi.org/10.1080/15502783.2024.2380058 (PubMed: pubmed.ncbi.nlm.nih.gov/39042054/)
- Australian Sports Commission. AIS Sports Supplement Framework: Creatine. Accessed 23 October 2026. www.ausport.gov.au/ais/nutrition/supplements/group_a/performance-supplements2/creatine
- Neves M Jr, Gualano B, Roschel H, et al. (2011). Effect of creatine supplementation on measured glomerular filtration rate in postmenopausal women. Applied Physiology, Nutrition, and Metabolism, 36(3), 419 to 422. doi.org/10.1139/h11-014 (PubMed: pubmed.ncbi.nlm.nih.gov/21574777/)
- Lugaresi R, Leme M, de Salles Painelli V, et al. (2013). Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein diet? Journal of the International Society of Sports Nutrition, 10(1), 26. doi.org/10.1186/1550-2783-10-26 (PubMed: pubmed.ncbi.nlm.nih.gov/23680457/)
- 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, 18(1), 13. doi.org/10.1186/s12970-021-00412-w (PubMed: pubmed.ncbi.nlm.nih.gov/33557850/)
- Gualano B, Ferreira DC, Sapienza MT, et al. (2010). Effect of short-term high-dose creatine supplementation on measured GFR in a young man with a single kidney. American Journal of Kidney Diseases, 55(3), e7 to e9. doi.org/10.1053/j.ajkd.2009.10.053 (PubMed: pubmed.ncbi.nlm.nih.gov/20060630/)
- Lopez RM, Casa DJ, McDermott BP, et al. (2009). Does creatine supplementation hinder exercise heat tolerance or hydration status? A systematic review with meta-analyses. Journal of Athletic Training, 44(2), 215 to 223. doi.org/10.4085/1062-6050-44.2.215 (PubMed: pubmed.ncbi.nlm.nih.gov/19295968/)
- Watson G, Casa DJ, Fiala KA, et al. (2006). Creatine use and exercise heat tolerance in dehydrated men. Journal of Athletic Training, 41(1), 18 to 29. No DOI; full text: pmc.ncbi.nlm.nih.gov/articles/PMC1421496/ (PubMed: pubmed.ncbi.nlm.nih.gov/16619091/)
- Lak M, Forbes SC, et al. (2025). Does creatine cause hair loss? A 12-week randomized controlled trial. Journal of the International Society of Sports Nutrition, 22(sup1), 2495229. doi.org/10.1080/15502783.2025.2495229 (PubMed: pubmed.ncbi.nlm.nih.gov/40265319/)
- van der Merwe J, Brooks NE, Myburgh KH. (2009). Three weeks of creatine monohydrate supplementation affects dihydrotestosterone to testosterone ratio in college-aged rugby players. Clinical Journal of Sport Medicine, 19(5), 399 to 404. doi.org/10.1097/JSM.0b013e3181b8b52f (PubMed: pubmed.ncbi.nlm.nih.gov/19741313/)
- Antonio J, Brown AF, Candow DG, et al. (2025). Part II. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Journal of the International Society of Sports Nutrition, 22(1), 2441760. doi.org/10.1080/15502783.2024.2441760 (PubMed: pubmed.ncbi.nlm.nih.gov/39720835/)
- Elosegui S, López-Seoane J, Martínez-Ferrán M, et al. (2022). Interaction between caffeine and creatine when used as concurrent ergogenic supplements: a systematic review. International Journal of Sport Nutrition and Exercise Metabolism, 32(4), 285 to 295. doi.org/10.1123/ijsnem.2021-0262 (PubMed: pubmed.ncbi.nlm.nih.gov/35016154/)
- Ostojic SM, Ahmetovic Z. (2008). Gastrointestinal distress after creatine supplementation in athletes: are side effects dose dependent? Research in Sports Medicine, 16(1), 15 to 22. doi.org/10.1080/15438620701693280 (PubMed: pubmed.ncbi.nlm.nih.gov/18373286/)
- Longobardi I, Gualano B, Seguro AC, Roschel H. (2023). Is it time for a requiem for creatine supplementation-induced kidney failure? A narrative review. Nutrients, 15(6), 1466. doi.org/10.3390/nu15061466 (PubMed: pubmed.ncbi.nlm.nih.gov/36986197/)
- Yoshizumi WM, Tsourounis C. (2004). Effects of creatine supplementation on renal function. Journal of Herbal Pharmacotherapy, 4(1), 1 to 7. No DOI. (PubMed: pubmed.ncbi.nlm.nih.gov/15273072/)
- Roitman S, Green T, Osher Y, et al. (2007). Creatine monohydrate in resistant depression: a preliminary study. Bipolar Disorders, 9(7), 754 to 758. doi.org/10.1111/j.1399-5618.2007.00532.x (PubMed: pubmed.ncbi.nlm.nih.gov/17988366/)
- Toniolo RA, Silva M, Fernandes FBF, et al. (2018). A randomized, double-blind, placebo-controlled, proof-of-concept trial of creatine monohydrate as adjunctive treatment for bipolar depression. Journal of Neural Transmission, 125(2), 247 to 257. doi.org/10.1007/s00702-017-1817-5 (PubMed: pubmed.ncbi.nlm.nih.gov/29177955/)
This article is general information, not medical advice. If you have a health condition, are pregnant or breastfeeding, or take medication, talk to your doctor before starting a supplement.
