BUN
A waste product cleared by the kidneys — used alongside creatinine.
What is it
Blood urea nitrogen reflects the body's protein metabolism waste cleared by the kidneys. Levels can be influenced by hydration, diet, and kidney function.
Why it's measured
BUN has been used alongside creatinine to evaluate kidney function and hydration status in research and clinical practice.
Reference range
Standard laboratory reference
7 – 20 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.
What results may indicate
Elevated
Has been associated with dehydration, reduced kidney function, or high protein intake in research literature.
Lower
May reflect low protein intake or overhydration.
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.
Related markers
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.
Explore the Apex 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.