Creatine, Your Kidneys and the Creatinine Test
One scoop of MemoryFuel carries 5 g of creatine, and creatine changes a common kidney blood test. Here is why that happens, and why it usually does not mean harm.
Why creatine confuses kidney tests
Labs estimate kidney function from blood creatinine, a waste product of creatine metabolism. Take extra creatine and you make extra creatinine, so the number can rise and the calculated eGFR can fall even when your kidneys are fine. A published case report describes a man whose "kidney problem" turned out to be his creatine supplement.[1]
The label's caution
What the safety research says
Studies in healthy athletes taking creatine for months to years found no impairment of kidney function, and the International Society of Sports Nutrition position stand considers creatine monohydrate safe for healthy people at standard doses.[2][3] A 2021 review of common misconceptions reached the same conclusion for healthy kidneys.[4]
Who should be careful
- People with chronic kidney disease or a single kidney
- People with diabetes or high blood pressure who have been told their kidney function is reduced
- People taking NSAIDs daily or other drugs that strain the kidneys
For these groups the question is not whether creatine is generally safe but whether it is safe for them, and that is a decision for their own doctor.
The magnesium angle
MemoryFuel also contains 300 mg of magnesium, which healthy kidneys clear easily. In kidney failure magnesium can build up, which is a second reason people with kidney disease should not start this product on their own.[5]
Practical steps before blood work
- Tell the clinician ordering the test that you take a creatine supplement, and how much.
- Ask whether they want you to pause it beforehand.
- If creatinine is borderline, ask whether a cystatin C test, which is not affected by creatine, would help.
Quick questions on this topic
Does creatine damage healthy kidneys?
Studies in healthy people taking creatine for months to years have not found kidney damage at usual doses.
Why did my creatinine go up on creatine?
Creatine breaks down into creatinine, the marker labs use to estimate kidney function, so levels can rise without any harm. Your doctor can interpret it, sometimes with a cystatin C test.
Should I stop creatine before a blood test?
Ask the clinician ordering the test. Some prefer a pause before kidney testing; all need to know you take it.
Sources behind this page
Every link opens the original abstract or agency page. Most trials gave creatine or a single nutrient on its own, often at other doses; none tested the MemoryFuel blend.
- 1Williamson L, New D. How the use of creatine supplements can elevate serum creatinine in the absence of underlying kidney pathology. BMJ Case Rep. 2014;2014:bcr2014204754. pubmed.ncbi.nlm.nih.gov/25239988/
- 2Poortmans JR, Francaux M. Long-term oral creatine supplementation does not impair renal function in healthy athletes. Med Sci Sports Exerc. 1999;31(8):1108-1110. pubmed.ncbi.nlm.nih.gov/10449011/
- 3Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. pubmed.ncbi.nlm.nih.gov/28615996/
- 4Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr. 2021;18(1):13. pubmed.ncbi.nlm.nih.gov/33557850/
- 5NIH Office of Dietary Supplements. Magnesium: Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
Run a fair 90-day MemoryFuel trial
Checkout happens on the maker's ClickBank page. Mix one scoop a day exactly as printed, write down a simple recall score on day one, keep the receipt email, and if nothing has moved by about day 75, email the helpdesk while the 90-day window is still open.