Biomarker · Liver
Bilirubin
Bilirubin is a yellow substance from the normal breakdown of red blood cells. What a bilirubin test shows about the liver and blood, including Gilbert's syndrome.
Written by LON6EVITY Editorial Team · Last updated
What bilirubin is
Bilirubin is made when red blood cells break down. The liver processes it so it can leave the body in bile.
What results can mean
MedlinePlus notes that high bilirubin can be caused by liver disease, bile duct blockage or faster-than-normal breakdown of red blood cells, and can cause jaundice. Gilbert syndrome, a common and harmless inherited condition, can cause mildly raised bilirubin.
Types measured
Tests may report total, direct (conjugated) and indirect (unconjugated) bilirubin; the pattern helps a clinician find where the problem is.
Reference ranges
Reference ranges differ between laboratories, units and methods, and depend on age, sex and your overall clinical picture. A single result is not a diagnosis — interpret it with a qualified clinician.
Factors that can affect the result
- Liver function
- Red blood cell breakdown
- Fasting
- Gilbert syndrome
Questions people commonly ask
- What is Gilbert syndrome?
- A common inherited condition causing mildly high bilirubin, often noticed during fasting or illness. It is generally harmless.
Related biomarkers
Related tests
Understand your biomarkers in context
What does this mean for your own health data? Log your results, follow trends over time and bring an organised summary to your next doctor's appointment.
Sources
- Bilirubin Blood Test. MedlinePlus, U.S. National Library of Medicine.