hs-CRP: Measuring the Inflammation Behind Chronic Disease
High-sensitivity C-reactive protein detects the low-grade, symptomless inflammation associated with cardiovascular disease, insulin resistance, and accelerated aging.
Board-Certified Nurse Practitioner, Trained in Functional/Integrative Medicine and Bioidentical Hormone Balancing
- Also known as
- High-sensitivity C-reactive protein, Cardiac CRP
- Measured in
- mg/L
- Typical lab range
- Under 3.0 mg/L considered average risk
- Often-targeted optimal
- Below 1.0 mg/L
What is hs-CRP?
C-reactive protein is produced by the liver in response to inflammatory signaling. The high-sensitivity assay can detect the small differences that matter for chronic disease risk — the range a standard CRP, designed to identify acute infection, cannot resolve.
Why does it matter?
Chronic low-grade inflammation is a shared mechanism across atherosclerosis, insulin resistance, autoimmune activity, and many of the processes grouped under biological aging. It rarely produces symptoms you can point to, which is precisely why measuring it is useful.
Inflammation and lipids are separate axes of risk. Two people with an identical ApoB can carry meaningfully different risk depending on their inflammatory state.
What does it tell us?
| hs-CRP | Common interpretation |
|---|---|
| Under 1.0 mg/L | Lower relative cardiovascular risk — the usual optimal target |
| 1.0–3.0 mg/L | Average relative risk; worth addressing modifiable drivers |
| Above 3.0 mg/L | Higher relative risk; look for a cause |
| Above 10 mg/L | Suggests acute inflammation or infection — repeat once resolved |
Why might it be missed on routine bloodwork?
Annual physicals often include no inflammatory marker at all, and when CRP is ordered it may be the standard rather than high-sensitivity assay. A standard CRP reported as normal cannot rule out the low-grade elevation hs-CRP is designed to find.
What can cause hs-CRP to be high?
- Recent infection, injury, dental infection, or surgery — the most common transient cause
- Visceral adiposity and insulin resistance
- Autoimmune and inflammatory conditions
- Smoking, excess alcohol, poor sleep, and chronic stress
- Intense exercise in the days before the draw
- Periodontal disease and untreated sleep apnea
- Estrogen-containing therapy, which can raise CRP without reflecting vascular inflammation
What can cause it to be low?
A low hs-CRP is the goal and generally reflects an absence of active inflammation. It is not a marker where lower becomes a problem, though it does not by itself exclude localized disease.
Questions to discuss with your healthcare provider
- Was this the high-sensitivity assay, and was I well when it was drawn?
- Should we repeat it in a few weeks to confirm the pattern?
- Do my ferritin, insulin, and lipid results point to the same driver?
- Which modifiable factors — sleep, dental health, alcohol, visceral fat — apply to me?
Frequently asked questions
What is an optimal hs-CRP level?
Below 1.0 mg/L is generally considered optimal, 1.0–3.0 mg/L average, and above 3.0 mg/L higher risk — provided you were free of acute illness or injury when the sample was drawn.
Can exercise raise hs-CRP?
Yes, temporarily. A hard training session or a race in the preceding days can elevate CRP. Regular exercise lowers it over time. Where possible, draw the sample after a couple of easier days.
Want to see your own data?
hs-CRP is a foundational marker in ClearSignal's Core Inflammation Panel, read alongside ferritin, homocysteine, and a full blood count so a single elevated value is interpreted in context.
Core Inflammation Panel
68 biomarkers · $249
Foundational inflammation testing to identify elevated inflammatory markers that may be driving chronic disease, fatigue, and accelerated aging.
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About the author
Erica Finnan, MSN, APRN-C
Board-Certified Nurse Practitioner, Trained in Functional/Integrative Medicine and Bioidentical Hormone Balancing
Founder, ClearSignal Health
Erica Finnan is a board-certified nurse practitioner trained in functional and integrative medicine and bioidentical hormone balancing. She personally reviews every ClearSignal lab report.
Read full author profileReferences
Medical Disclaimer
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