Interleukin-6: normal range and what it means
A signalling protein that drives inflammation.
Normal range
Adult reference range.
- Optimal< 1.8 pg/mL
- Elevated1.8 – 5 pg/mL
- High≥ 5 pg/mL
What it measures
A signalling protein released by immune cells and by fat tissue, and the thing that tells the liver to make CRP. It sits upstream of most of the inflammation you can measure.
What moves it
Acute infection, injury, intense exercise, poor sleep and body fat. Short-lived spikes after hard training are normal.
How to bring it into range
Fat loss, regular exercise, decent sleep and treating any ongoing infection. It rises sharply for a day or two after hard training.
How fast it responds
Days to weeks.
Also reported as: il-6 · il6
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Common questions
- What is a normal Interleukin-6 level?
- Optimal: < 1.8 pg/mL. Adult reference range.
- What does a high Interleukin-6 mean?
- A value above the reference band means Interleukin-6 is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my Interleukin-6?
- Fat loss, regular exercise, decent sleep and treating any ongoing infection. It rises sharply for a day or two after hard training.
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Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.