What hs-CRP is
C-reactive protein is an acute-phase protein produced by the liver in response to IL-6 (interleukin-6) signaling. IL-6 is released by immune cells and adipose tissue during inflammation. CRP rises rapidly with acute inflammation and falls when inflammation resolves.
"High-sensitivity" CRP uses a more sensitive assay capable of detecting low-grade chronic inflammation invisible to standard CRP testing.
vs standard CRP
- Standard CRP, detects significant inflammation (acute infection, severe illness); ranges 0-250+ mg/L
- hs-CRP, detects low-grade chronic inflammation; ranges 0-10 mg/L typically
For cardiovascular and metabolic risk assessment, hs-CRP is required.
Reference ranges
- <1.0 mg/L: Optimal (low cardiovascular risk)
- 1.0-3.0: Moderate risk
- >3.0: High risk
- >10: Acute inflammation; recheck after recovery
What raises hs-CRP
- Visceral fat / obesity
- Insulin resistance / metabolic syndrome
- Smoking
- Poor sleep / sleep apnea
- Chronic stress
- Periodontal disease
- Subclinical infections
- Some autoimmune conditions
- Acute illness or injury (transient)
What lowers hs-CRP
- Weight loss (especially visceral fat)
- Exercise (regular)
- Statins
- GLP-1 therapy (substantial reduction)
- Mediterranean-pattern diet
- Smoking cessation
- Sleep optimization
- Address sleep apnea
- Stress reduction
- Address periodontal disease
Use cases
- Cardiovascular risk stratification (alongside lipids)
- Tracking response to anti-inflammatory interventions
- Identifying chronic inflammation in symptomatic patients
- Re-evaluation if elevated (rule out acute illness)
The clinical pearl: hs-CRP is the cheapest, most widely available marker of chronic inflammation. Track it baseline and at follow-up after lifestyle or therapeutic interventions, particularly GLP-1 therapy, weight loss, or smoking cessation.
Bottom line
hs-CRP is the workhorse inflammation marker. Optimal under 1.0 mg/L. Useful for cardiovascular risk stratification and tracking interventions. Acute illness raises it transiently, interpret in context. Many lifestyle and therapeutic interventions move it substantially.