Is creatine bad for your kidneys?

Short answer

Not for healthy people. Creatine raises the kidney number on a blood test (creatinine), but that is because creatine's breakdown product goes up. Kidney function measured with a precise test stayed the same.

Is creatine bad for your kidneys?
'Creatine → higher kidney number → kidney damage' — does this formula hold?
A common story: someone takes creatine, gets a checkup, and their kidney number comes back high. That is how the idea spread that creatine damages your kidneys. We checked this formula one step at a time.
The kidney number does go up
Across 20 studies, creatinine rose by 0.13 on average
A 2026 analysis that pooled 19 randomized trials and 1 crossover trial found that people taking creatine had blood creatinine about 0.13 higher on average. But in the same analysis, two other kidney markers, urea and estimated kidney function, showed no difference.
But that number is creatine's breakdown product
It rises when muscles hold more creatine
The creatinine on a checkup is what is left after creatine is used. So taking creatine raises this number on its own, separate from the kidneys. A 2025 analysis also found the rise was clear within the first week.
Measured precisely, kidney function did not change
An analysis of 1,036 people: the precise test stayed the same
A 2026 analysis of 26 trials and 1,036 people found that kidney function calculated from creatinine came out 10.75 lower. But kidney function measured with a precise test that does not use creatinine showed no difference. Protein and albumin in urine, and urea, were also the same.
Same result with a high-protein diet
26 people, 12 weeks, kidney function unchanged
For 12 weeks, 26 people lifted and ate a lot of protein (about 84-217 g a day for a 70 kg (154 lb) person) while taking creatine or a placebo. Precisely measured kidney function went from 101 to 109 with creatine and from 103 to 107 with placebo. There was no difference.
Taking it for years changed nothing either
Up to 5 years on creatine, kidneys were normal
People who had taken creatine for 10 months to 5 years were compared with people who had not. Kidney filtering and protein leakage were no different. In a trial where 18 people took about 10 g a day for 3 months, a kidney marker unrelated to creatinine did not get worse.
There is one exception case
1 case: kidneys injured after high-dose loading
In 2025, doctors reported 1 person who developed acute kidney injury after 6 days of high-dose loading. This is 1 person's case, not a trial result. If you get a blood test while taking creatine, telling your doctor is enough. That way a raised number is not mistaken for kidney disease.
Bottom line: creatine was not bad for healthy kidneys
The test number rose; kidney function stayed the same
Creatine raises your creatinine number. But precisely measured kidney function stayed the same in a 12-week trial and in people who took it for 5 years. Taking about 5 g a day, the dose used in the trial, and mentioning it at blood tests is enough.