NST research

Is creatine safe for your kidneys?

The cited short trials provide reassurance for the populations and protocols studied, not a guarantee for every reader. Creatine can influence creatinine-based kidney estimates, but that does not establish why an individual result is abnormal. Do not dismiss a raised creatinine or lower eGFR as a supplement effect without clinical assessment.
Research-basedReviewed by Gabriel SilvaLast verified 12 September 2026Next review due 14 March 2027Report a correction

The evidence-led answer

NST verdict

The cited short trials provide reassurance for the populations and protocols studied, not a guarantee for every reader. Creatine can influence creatinine-based kidney estimates, but that does not establish why an individual result is abnormal. Do not dismiss a raised creatinine or lower eGFR as a supplement effect without clinical assessment.

Does creatine damage healthy kidneys?

The cited trials are limited to specific populations and protocols. In a 12 week randomised, placebo controlled trial, resistance trained people already eating a high protein diet took creatine, a 5 day 20 g/day loading phase, then 5 g/day. Kidney filtration was measured with 51Cr EDTA clearance, a reference method, not an estimate, and showed no significant change; creatinine clearance, urea, electrolytes, protein in the urine and albumin in the urine all stayed put. A separate 12 week randomised trial in postmenopausal women used the same measured method and also found kidney filtration unchanged.

The 2023 narrative review discusses reassuring controlled evidence, but its conclusions must be read alongside study populations, duration and methods. It is not proof of universal safety.

Then why did my creatinine go up?

Creatine supplementation is one factor that can influence creatinine-based estimates of kidney function. An abnormal result can also reflect a kidney problem. Taking creatine does not, by itself, distinguish those possibilities.

Tell the clinician interpreting your results about all supplements you take. Follow their advice on further tests, timing and whether to change supplement use. This article cannot determine the cause or recommend a fixed stop-and-retest interval.

Who should be cautious?

If you have a kidney condition, reduced kidney function, are on dialysis or have a single kidney, seek individual medical advice before taking creatine. Evidence from other populations is not personal clearance. Trial duration, sample size and other differences also limit the evidence.

What this means in practice

Do not use this article to self-diagnose an abnormal kidney result or to choose a dose on the assumption that your kidneys are healthy. Tell your clinician about creatine and other supplements, and follow their investigation advice. Seek individual advice before starting if you have a kidney condition.

Practical meaning

Do not use this article to self-diagnose an abnormal kidney result or to choose a dose on the assumption that your kidneys are healthy. Tell your clinician about creatine and other supplements, and follow their investigation advice. Seek individual advice before starting if you have a kidney condition.

Limitations and uncertainty

The cited filtration trials are small and short. They do not establish safety for every population or explain an individual's abnormal result. Clinical interpretation and testing decisions belong with the treating clinician. Full-text and newer-evidence review remain outstanding.

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Evidence behind this page

What the evidence says, and where it stops.

Controlled trials that measured kidney filtration directly found no harm from creatine

moderate confidence

The trials address specific populations and protocols. In a 12 week randomised, placebo controlled trial, resistance trained people already eating a high protein diet (at least 1.2 g/kg/day) took creatine (20 g/day for 5 days then 5 g/day); glomerular filtration rate measured by 51Cr EDTA clearance, a reference method, not an estimate, showed no significant change, and creatinine clearance, urea, electrolytes, proteinuria and albuminuria all stayed put. A separate 12 week randomised trial in postmenopausal women used the same measured method and also found glomerular filtration rate unchanged. A 2023 review of this literature reaches the same conclusion: controlled trials do not support the kidney damage concerns raised by a handful of case reports and animal studies, and the reviewed studies provide reassurance within their populations and follow-up, not a universal guarantee. These are controlled trials measuring it directly, not proof of safety forever, they are small (dozens of participants) and 12 weeks long.

Study context and sources
Who it may apply to
Healthy resistance trained adults on a high protein diet; postmenopausal women; adults without kidney disease across the review.
Limitations
Two single trials, modest samples, 12 weeks; strong design but short; the review is narrative and by a group focused on creatine safety.

Sources

Creatine may affect creatinine estimates; abnormal results still need assessment

moderate confidence

Creatine supplementation is one factor that can influence creatinine-based estimates of kidney function. An abnormal result can also reflect a kidney problem. Taking creatine does not, by itself, distinguish those possibilities. Tell the clinician interpreting your results about all supplements you take. Follow their advice on further tests, timing and whether to change supplement use. This article cannot determine the cause or recommend a fixed stop-and-retest interval.

Study context and sources
Who it may apply to
General; mechanism established in the review, clinical resolution is standard practice.
Limitations
No individual diagnostic conclusion or fixed retesting protocol is established here. Clinical-boundary review remains required.

Sources

Population limits prevent a universal safety or dosing recommendation

moderate confidence

If you have a kidney condition, reduced kidney function, are on dialysis or have a single kidney, seek individual medical advice before taking creatine. Evidence from other populations is not personal clearance. Trial duration, sample size and other differences also limit the evidence. Do not use this article to self-diagnose an abnormal kidney result or to choose a dose on the assumption that your kidneys are healthy. Tell your clinician about creatine and other supplements, and follow their investigation advice. Seek individual advice before starting if you have a kidney condition.

Study context and sources
Who it may apply to
General adults; people with kidney conditions directed to individual medical advice.
Limitations
Study populations and duration limit applicability. This is not an individual suitability assessment.

Sources

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