Quick answer
For healthy adults, current evidence does not show that standard creatine monohydrate supplementation damages kidney function.
However, creatine can increase serum creatinine, the marker commonly used to estimate kidney function. That can make a creatinine-based eGFR appear lower even when actual filtration has not worsened.
That distinction matters.
1. Why creatine and creatinine get confused
Creatine and creatinine are related, but they are not the same thing.
Creatine is stored largely in muscle and helps provide rapid energy during high-intensity activity. A small amount naturally converts to creatinine, which is then cleared from the blood by the kidneys.
Because blood creatinine is commonly used to estimate kidney filtration, a rise in creatinine can look concerning. But if you are taking extra creatine, some of that increase may reflect creatine metabolism, rather than reduced kidney filtration.
eGFR means estimated glomerular filtration rate. A creatinine-based eGFR is calculated from a blood marker; it is not a direct measurement of filtration.
2. What does the newer evidence show?
A 2025 systematic review and meta-analysis found that creatine supplementation produced a modest increase in serum creatinine, but did not produce a statistically significant reduction in GFR compared with controls. The authors concluded that the creatinine increase was more consistent with metabolic turnover than kidney impairment.
A separate 2026 systematic review of 26 studies found a similar pattern. Creatine increased serum creatinine and lowered kidney function estimates when those estimates were calculated from creatinine itself.
But when kidney filtration was assessed using Cr-EDTA, rather than a creatinine-based estimate, there was no significant reduction. The review also found no significant differences in urea, albuminuria or proteinuria.
3. So is creatine safe for healthy kidneys?
The Australian Institute of Sport states that research does not support claims of systematic renal dysfunction associated with creatine monohydrate supplementation.
Most safety and efficacy evidence concerns creatine monohydrate. Findings about that form should not automatically be transferred to every alternative formulation or multi-ingredient supplement.
For healthy people using established protocols, the evidence that creatine monohydrate causes kidney damage is weak. That does not mean every product, dose or personal health situation is equivalent.
4. A higher creatinine result should not simply be ignored
This is where nuance matters. An abnormal result still needs assessment. Creatine use is relevant context, not a diagnosis or a reason to dismiss the result.
Your health professional may consider:
- Previous results
- Creatine use and dose
- Hydration
- Muscle mass and recent exercise
- Medications
- Underlying health conditions
- Other kidney markers
The sensible step is to tell the health professional interpreting your blood test that you use creatine.
5. What if you already have kidney disease?
Most reassuring evidence is in people without established kidney disease. Evidence in people with chronic kidney disease is more limited, so the same reassurance cannot simply be assumed.
If you have kidney disease, unexplained abnormal kidney tests, or take medicines that affect kidney function, discuss supplementation with your clinician.
6. What should you do before a blood test?
Tell your doctor or pathology clinician that you take creatine. Include:
- The form you use, including whether it is creatine monohydrate
- How much you take
- How long you have taken it
- Whether you recently completed a loading phase
The goal is to have results interpreted in context. Your clinician can decide whether further assessment is needed.
The 1% Better takeaway
Creatine can make a kidney blood test look different. That is not the same thing as proving kidney damage.
Current evidence suggests that in healthy adults, creatine monohydrate can modestly increase serum creatinine without clear evidence of impaired kidney filtration.
The better question is not: “Did my creatinine go up?”
It is: “What does the full kidney assessment show, and does my clinician know I take creatine?”
That is a much more useful conversation.
Check the form, evidence and cost per 5 g.
Sources and evidence notes
Evidence checked on 15 October 2026. This article explains published research; it does not diagnose kidney disease or establish the safety of a specific product. Research findings depend on the populations, protocols and assessment methods studied.
- Kabiri Naeini and colleagues, BMC Nephrology, 2025Systematic review and meta-analysis: a modest rise in serum creatinine, without a statistically significant difference in GFR. Studies varied in population, dose, duration and kidney assessment.
- de Souza Almeida and colleagues, International Urology and Nephrology, 2026Systematic review of 26 trials, separating creatinine-based filtration estimates from Cr-EDTA measurements. The absence of significant changes in selected markers is reassuring, but does not establish safety for every person or every duration of use.
- Australian Institute of Sport, CreatineAustralian guidance on creatine monohydrate, the form underlying most safety and efficacy evidence, and established supplementation protocols.
- Australian Institute of Sport, Concerns and considerationsAIS guidance on the research behind adverse-effect claims and practical considerations when using creatine monohydrate.