A waste product cleared by the kidneys — primary marker of kidney function.
What is it
Creatinine is produced from muscle metabolism and cleared by the kidneys. Blood levels reflect the balance of muscle production and kidney clearance.
Why it's measured
Creatinine has been the foundational marker of kidney function in clinical practice and research for decades.
Reference range
Standard laboratory reference
Men: 0.7 – 1.3 / Women: 0.6 – 1.1 mg/dL
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
Where does your number land?
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Drag to your own Creatinine result.
Educational only, not a diagnosis. Ranges vary by laboratory. See which panel includes Creatinine.
What results may indicate
Elevated
Has been associated with reduced kidney function in research literature.
Lower
Often reflects low muscle mass.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
Part of standard metabolic panels and routine physicals.
Related markers
Common questions
Creatinine is produced from muscle metabolism and cleared by the kidneys. Blood levels reflect the balance of muscle production and kidney clearance.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. Creatinine is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
Creatinine is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Related symptoms
A symptom is a signal, not a diagnosis. These guides explain what the evidence shows and the blood markers, including this one, that help find the cause.
Creatinine is a breakdown product of muscle, so more muscle means more of it in your blood. A lifter with a high creatinine reading and no other abnormal kidney markers is often looking at their own muscle mass rather than a kidney problem, and a hard session in the days before a draw can raise it further. Worth mentioning to your physician before anyone concludes anything from a single number. If you want a structured place to start, the training library lists every programme we publish by days per week and equipment.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Find the right panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.
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The whole picture in one sitting: who it suits, what the labs decide, what the first year actually looks like. Every clinical claim is cited.
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