One of the biggest myths about creatine is that it damages your kidneys. Some claim it causes kidney disease. Others say it leads to kidney cancer. These are serious claims. So let’s look at what actual human research shows.
What Your Kidneys Actually Do
Your kidneys filter waste from your blood. One of those waste products is creatinine.
Doctors use blood creatinine levels to estimate kidney function using something called eGFR (estimated glomerular filtration rate).
Here’s where confusion happens:
Creatine supplements can slightly increase blood creatinine levels. But that does not automatically mean kidney damage.
Creatine vs. Creatinine
Creatine helps your muscles produce energy.
Creatinine is a breakdown product of creatine.
When you supplement with creatine, some of it converts into creatinine. That can raise blood creatinine slightly, even if kidney function is completely normal.
A 2025 meta-analysis reviewing 21 clinical trials found:
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Small increases in serum creatinine
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No significant reduction in measured kidney filtration (GFR)
Read the study here:
👉 https://link.springer.com/article/10.1186/s12882-025-04558-6
This is the key distinction: creatinine can rise without kidney damage.
What Controlled Human Studies Show
Several clinical trials have directly measured kidney function using gold-standard methods.
Neves et al., 2011
Postmenopausal women took creatine for 12 weeks.
Measured GFR using a precise tracer method showed no change in kidney filtration.
👉 https://doi.org/10.1139/H11-014
Lugaresi et al., 2013
Resistance-trained individuals consuming high protein diets took creatine for 12 weeks.
Measured GFR, creatinine clearance, and urinary albumin remained normal.
👉 https://link.springer.com/articles/10.1186/1550-2783-10-26
Vilar Neto et al., 2020
Healthy men supplemented with creatine.
Kidney injury biomarkers (KIM-1 and MCP-1) did not increase.
👉 https://academic.oup.com/toxres/article/9/3/263/5835504
Across controlled trials in healthy adults, kidney filtration remains stable.
The International Society of Sports Nutrition also concluded that creatine supplementation does not impair kidney function in healthy individuals when used at recommended doses:
👉 https://link.springer.com/article/10.1186/s12970-017-0173-z
Does Creatine Cause Kidney Disease?
There is no high-quality human evidence showing creatine causes chronic kidney disease in healthy people.
A 2025 comprehensive safety review published in Frontiers in Nutrition concluded there is no convincing evidence linking creatine supplementation to kidney dysfunction in healthy populations:
👉 https://www.frontiersin.org/articles/10.3389/fnut.2025.1682746/full
What About Kidney Cancer?
There is no clinical evidence linking creatine to kidney cancer in humans.
No major nephrology organization or clinical trial identifies creatine as a carcinogen. Current human data does not support this claim.
Why the Myth Exists
The myth likely started because:
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Creatine can raise blood creatinine.
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High creatinine is associated with kidney disease.
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People assumed creatine caused kidney damage.
But elevated creatinine alone does not equal kidney injury.
Doctors sometimes use additional markers such as:
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Cystatin C
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Measured GFR
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Urine albumin
These give a clearer picture of true kidney function.
What If Someone Already Has Kidney Disease?
Most creatine studies exclude people with chronic kidney disease (CKD). That means safety data in this group is limited.
There are rare case reports of kidney injury in individuals taking creatine, such as this one:
👉 https://academic.oup.com/ckj/article/4/1/23/376016
However, case reports cannot prove causation.
If someone has CKD, creatine should only be used under supervision from a nephrologist.
Kidney nutrition guidelines emphasize medical oversight in CKD patients:
KDOQI 2020 Guidelines:
👉 https://www.ajkd.org/article/S0272-6386(20)30726-5/fulltext
The Real Causes of Kidney Disease
The leading causes of kidney disease are:
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Diabetes
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High blood pressure
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Long-term NSAID overuse
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Severe dehydration
These are well-established risk factors according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK):
👉 https://www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/prevention
Creatine supplementation in healthy adults is not listed among primary causes of kidney disease.
Bottom Line
For healthy individuals:
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Creatine does not reduce kidney filtration rate.
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Creatine does not cause chronic kidney disease in controlled trials.
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Small increases in creatinine are expected and not harmful.
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There is no strong human evidence linking creatine to kidney cancer.
For individuals with kidney disease:
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Safety data is limited.
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Medical supervision is required.
Creatine is one of the most studied supplements in sports nutrition. The kidney damage myth is not supported by high-quality human research in healthy populations.