Acute inflammation heals you; chronic, low-grade inflammation slowly wears you down. It rises with age — 'inflammaging' — and a simple blood marker, hs-CRP, offers a window onto it.
Inflammation has two faces. The acute kind — redness, swelling, fever — is the immune system doing its job, and it resolves. The other kind is quiet and chronic: a persistent, low-grade activation of the immune system that tends to rise with age. Researchers call it 'inflammaging,' and it is increasingly seen as a common thread running through many of the diseases of later life.
Two kinds of inflammation
Acute inflammation is short-lived and protective: it clears infections and repairs injury, then switches off. Chronic low-grade inflammation is different — a smouldering, systemic activation that does not resolve, often without any obvious trigger. With age this background level tends to creep upward, a pattern named 'inflammaging' (Franceschi & Campisi, 2014).
This slow fire is thought to both reflect and accelerate biological aging. It is fed by factors like visceral fat, chronic infections, a sedentary lifestyle and cellular 'senescence,' and in turn it damages tissues over years — which is why it links so many age-related conditions together (Ferrucci & Fabbri, 2018).
What the markers measure
The most widely used marker is high-sensitivity C-reactive protein (hs-CRP), a protein the liver makes in response to inflammatory signalling; the 'high-sensitivity' assay detects the low levels relevant to chronic, rather than acute, inflammation. Interleukin-6 (IL-6) is another commonly studied signal, upstream of CRP.
These are screens, not diagnoses, and they need context: an acute infection, injury or intense exercise can transiently raise CRP, so a single high reading taken when you are unwell means little. What is informative is your baseline level when you are healthy, ideally confirmed on a repeat test.
Why they track with longevity
Elevated inflammatory markers predict future disease with striking consistency. In healthy women, baseline hs-CRP predicted future heart attacks and strokes, adding information beyond cholesterol (Ridker et al., 2000). In older adults, higher IL-6 and CRP were associated with greater mortality and physical decline (Harris et al., 1999).
Crucially, inflammation appears to be part of the causal chain, not merely a bystander. In the CANTOS trial, a drug that lowered inflammation without touching cholesterol reduced cardiovascular events (Ridker et al., 2017) — evidence that the fire itself does damage, and that cooling it can help.
What actually cools it
Much of what lowers chronic inflammation is the same foundation that helps everything else: regular physical activity, not smoking, reaching a healthy amount of visceral fat, a dietary pattern rich in vegetables, fruit, fish and whole grains (such as the Mediterranean pattern), sufficient sleep and treating chronic sources like gum disease. These act on the roots of inflammaging rather than masking it.
If you want to track it, an hs-CRP test is inexpensive and widely available; measure it when you are well and watch the trend over time rather than fixating on one value. Interpret an elevated result with a qualified professional, who can look for a specific cause and place it alongside your other markers.
References
Ferrucci L., Fabbri E. (2018). Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty. Nature Reviews Cardiology, 15(9), 505–522.
Franceschi C., Campisi J. (2014). Chronic inflammation (inflammaging) and its potential contribution to age-associated diseases. Journals of Gerontology Series A, 69(Suppl 1), S4–S9.
Ridker P.M. et al. (2000). C-reactive protein and other markers of inflammation in the prediction of cardiovascular disease in women. New England Journal of Medicine, 342(12), 836–843.
Ridker P.M. et al. (2017). Antiinflammatory therapy with canakinumab for atherosclerotic disease (CANTOS). New England Journal of Medicine, 377(12), 1119–1131.
Harris T.B. et al. (1999). Associations of elevated interleukin-6 and C-reactive protein levels with mortality in the elderly. American Journal of Medicine, 106(5), 506–512.
Articles in this section are educational and are not medical advice, a diagnosis, or a prescription. Consult a qualified professional before acting on anything you read here.
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