hs-CRP (high-sensitivity C-reactive protein)

A blood marker of low-grade inflammation in the body.

What it measures

C-reactive protein, a protein made by the liver that rises with inflammation — the “high-sensitivity” version detects the low levels relevant to long-term health.

Why it matters

Chronic low-grade inflammation tracks with cardiovascular and metabolic risk. A low hs-CRP is reassuring; a persistently raised one is worth understanding.

Healthy target

< 1.0 mg/L

How to read your value

hs-CRP spikes with any infection, injury or recent intense exercise, so a single high reading is often just a temporary blip. Retest when well and rested before reading anything into it. Very high values reflect acute illness, not chronic risk.

What can affect it

• Any recent infection, illness or injury (temporary)
• Body fat and metabolic health
• Smoking
• Physical activity and diet quality lower it over time

Does the target differ by age or sex?

Same target for men and women. It runs a little higher on average with more body fat and with age, and transiently in pregnancy.

When to talk to a clinician

A persistently raised hs-CRP with no obvious cause should be reviewed by a clinician.