High-Sensitivity C-Reactive Protein (hs-CRP)
High-sensitivity C-reactive protein (hs-CRP) is a blood test that measures low-level inflammation, which is often quietly elevated in people living with obesity.
Plain English
Patient-Friendly Explanation
C-reactive protein (CRP) is a substance the liver makes when the body is inflamed, and the high-sensitivity version of the test (hs-CRP) is sensitive enough to detect the low, smouldering level of inflammation that does not cause symptoms. Fat tissue — especially belly fat — releases signals that keep this inflammation switched on, which is why hs-CRP levels are often higher in people with excess weight. The test is used alongside cholesterol readings to estimate heart and blood-vessel risk, and levels tend to fall as weight is lost. It is not a diagnosis on its own, and a very high reading usually means an acute infection or injury rather than a metabolic issue.
Medical
Clinical Definition
hs-CRP is measured by high-sensitivity immunoassay (lower detection limit around 0.1 mg/L) and, per AHA/CDC guidance, stratifies cardiovascular risk as low (<1 mg/L), average (1–3 mg/L) or high (>3 mg/L) when used with lipid assessment. In obesity, expanded and inflamed adipose tissue — particularly visceral depots — releases interleukin-6, which drives hepatic CRP synthesis, so hs-CRP correlates with adiposity, insulin resistance and metabolic syndrome; weight loss of 5–10% measurably lowers it. Levels above 10 mg/L should prompt a search for acute inflammation or infection rather than being read as metabolic risk. hs-CRP is a risk marker, not a standalone diagnostic, and adds most value when the clinical question is overall cardiometabolic risk in a person with excess weight.
Key Insight
Why It Matters
Standard cholesterol checks can miss the inflammatory half of heart risk. We include hs-CRP in metabolic screening for patients with excess weight so that risk is assessed from both angles, and we use falling levels as one sign that the plan is working.
Sources
Reviewed against standard medical references.
Medically reviewed by
Family Physician & Registered Acupuncturist, Accord Medical Clinic. MBBS (NUS), Graduate Diploma in Family Medicine (NUS), Graduate Diploma in Acupuncture (Singapore College of TCM).
Last reviewed: September 2026
This page is general health education, not medical advice. Whether any treatment is appropriate for you is a decision made in consultation after assessment.
