Does creatine raise creatinine and damage your kidneys?

Here's what actually happens on a blood test. Creatine breaks down into creatinine — and creatinine is the number labs use to estimate kidney function (via eGFR). So if you supplement creatine and carry more muscle, your creatinine can read slightly high without anything being wrong with your kidneys. Attia and Layne Norton make this point explicitly in their dedicated creatine deep dive: elevated creatinine in creatine users is often a result of muscle mass rather than kidney damage.

The fix is a better test. Attia recommends cystatin C — a kidney marker that isn't thrown off by muscle mass or creatine — for an accurate assessment. If your doctor flags a high creatinine and you supplement creatine, tell them you take it and ask for cystatin C before drawing any conclusions.

On the broader safety question, this is one of the highest-consensus supplements in our data (4.6/5). Patrick's episode with creatine researcher Dr. Darren Candow debunks the kidney-damage, dehydration, and hair-loss myths directly. Attia calls monohydrate the gold standard at 5g/day with no cycling needed. The one real caveat every expert keeps: people with pre-existing kidney disease should talk to their physician first, since impaired kidneys may not handle the extra metabolic load.