High-Sensitivity CRP: The Inflammation Marker That Predicts Everything

High-sensitivity C-reactive protein — hs-CRP — is the single best operational marker of systemic, low-grade chronic inflammation in routine clinical practice. Levels predict cardiovascular events independently of LDL cholesterol, predict cognitive decline independently of cardiovascular risk, predict cancer incidence in multiple cohort analyses, and predict all-cause mortality with magnitude comparable to traditional risk factors. The Paul Ridker JUPITER trial (NEJM 2008) — which enrolled adults with normal LDL but elevated hs-CRP — established that statin therapy reduced cardiovascular events by 44 percent in that population, fundamentally reframing how the field thinks about residual cardiovascular risk. Peter Attia routinely runs it. Casey Means includes it in the metabolic-inflammation framework. The marker costs $20 to $40 to test.

And yet most adults don't know their number — because hs-CRP, like apoB and homocysteine, isn't part of the standard annual lipid panel. The high-sensitivity variant is specifically engineered to detect the low-grade inflammation that drives chronic disease (versus the high-CRP-only variant that flags acute infection). Adults running a longevity protocol who measure hs-CRP find a meaningful fraction in the elevated zone — often from undiagnosed metabolic syndrome, undertreated periodontal disease, sleep apnea, abdominal adiposity, or low-grade infections that the rest of the panel doesn't reveal.

What follows: the biology of CRP and what hs-CRP actually measures, the threshold targets that emerge from the cardiovascular and cognitive literature, the JUPITER framework and what it changed about residual cardiovascular risk, the lifestyle and pharmacological interventions that move hs-CRP, how to test it correctly (the variant matters), and how hs-CRP integrates with the broader Attia/Means/Dayspring biomarker stack — apoB, Lp(a), Omega-3 Index, homocysteine, fasting insulin.

What hs-CRP Actually Measures

C-reactive protein is an acute-phase reactant produced by the liver in response to inflammatory cytokines, particularly interleukin-6 (IL-6). The hepatic CRP production is downstream of essentially any inflammatory stimulus — bacterial or viral infection, sterile tissue injury, autoimmune flares, metabolic stress, low-grade adipose inflammation. The level rises within hours of an inflammatory stimulus and falls within days of resolution.

The "high-sensitivity" variant of the CRP assay is the same biological measurement but performed with a different antibody and detection chemistry that can resolve down to ~0.1 mg/L (compared to the standard CRP assay's ~5 mg/L floor). This sensitivity matters because the chronic low-grade inflammation that drives atherosclerosis, neurodegeneration, and metabolic dysfunction sits in the 0.5-5 mg/L range — invisible to the standard CRP assay, fully resolved by hs-CRP.

The biology hs-CRP captures has been termed "inflammaging" by Franceschi and others — the chronic, sterile, low-grade inflammation that accumulates with age and that mechanistically drives most age-related disease. Inflammaging is upstream of atherosclerosis (NLRP3 inflammasome activation in plaque macrophages), of neurodegeneration (microglial activation), of insulin resistance (adipose tissue macrophage infiltration), and of sarcopenia (chronic muscle catabolism). hs-CRP is the single number that operationalizes that biology in clinical practice.

The Thresholds That Matter

The Ridker framework, validated across multiple cohort studies and now embedded in the AHA/CDC cardiovascular risk guidance, identifies three hs-CRP zones:

• Below 1.0 mg/L — Low cardiovascular risk. The target zone for adults pursuing aggressive cardiovascular and cognitive longevity. Below this threshold, hs-CRP is not adding meaningful risk to the overall panel.
• 1.0-3.0 mg/L — Intermediate risk. Approximately 30-40 percent of US adults sit in this zone. The Reynolds Risk Score and other clinical models add risk for adults in the intermediate hs-CRP range — and intervention to lower hs-CRP into the low-risk zone produces measurable cardiovascular benefit.
• Above 3.0 mg/L — High cardiovascular risk. Materially elevated rate of cardiovascular events independent of LDL. Strong indication to identify the upstream inflammatory driver (metabolic syndrome, periodontal disease, sleep apnea, chronic infection, autoimmune process) and address it.
• Above 10 mg/L — Acute inflammation. Almost always reflects an active infection, recent injury, or autoimmune flare rather than chronic inflammaging. Repeat the test in 2-4 weeks once the acute event has resolved; chronic-risk interpretation requires non-acute samples.

The population distribution: median US adult hs-CRP sits around 1.5-2.0 mg/L. Lean, active, metabolically healthy adults often run below 0.5 mg/L. Adults with metabolic syndrome, abdominal obesity, or untreated periodontal disease often run above 4 mg/L. The variance within an individual over time is meaningful — hs-CRP should be tested at least twice (separated by 2-4 weeks, in the absence of acute illness) to establish a stable baseline before deciding on intervention.

What the JUPITER Trial Actually Showed

The JUPITER trial (Ridker et al., NEJM 2008) randomized 17,802 adults with LDL below 130 mg/dL but hs-CRP above 2.0 mg/L to rosuvastatin 20 mg daily or placebo. These were adults who would not have qualified for statin therapy under the LDL-focused guidelines of the time — yet their elevated hs-CRP suggested elevated residual cardiovascular risk despite normal LDL.

The result reframed the field: rosuvastatin produced a 44 percent reduction in the composite cardiovascular endpoint (MI, stroke, hospitalization for unstable angina, revascularization, cardiovascular death). The trial was stopped early for benefit. The mechanism is partially the statin's LDL-lowering (which still occurred even from "normal" baseline) and partially the statin's direct anti-inflammatory effect (statins lower hs-CRP by 20-40 percent independent of their lipid effect).

The clinical interpretation that's emerged: adults with elevated hs-CRP have meaningful residual cardiovascular risk that the LDL panel misses. The Attia/Dayspring clinical model places hs-CRP alongside apoB as the two foundational cardiovascular markers — apoB captures the particle-mediated atherosclerotic process; hs-CRP captures the inflammatory amplifier that determines whether plaque becomes clinically dangerous. Adults with low apoB and low hs-CRP are at low cardiovascular risk even with imperfect lifestyle. Adults with elevated either are at elevated risk regardless of how good the lipid panel looks.

The Cognitive Longevity Side

The hs-CRP-cognition relationship has emerged from multiple cohort studies — Framingham, Rotterdam, Atherosclerosis Risk in Communities (ARIC). Elevated mid-life hs-CRP predicts incident dementia decades later, independent of cardiovascular and metabolic risk factors. The mechanism is microglial activation: chronic systemic inflammation produces sustained microglial activation in the brain, and chronic microglial activation drives neurodegenerative pathology.

The integrated cognitive-cardiovascular framework that emerges: hs-CRP elevation in middle age is a single number that captures inflammation-mediated risk for both cardiovascular events in the 60s and 70s and cognitive decline in the 70s and 80s. The same intervention stack — lifestyle modification, treating upstream drivers, sometimes pharmacological — reduces both endpoints simultaneously. This is the convergence Attia argues for: longevity-grade cardiovascular protocol and longevity-grade cognitive protocol are the same protocol.

What Drives Elevated hs-CRP — And How to Lower It

Elevated hs-CRP is almost never a primary disease in itself. It's a marker of an upstream inflammatory driver. The clinical workup follows the differential:

• Metabolic syndrome and visceral adiposity. The single largest contributor to elevated hs-CRP in modern populations. Adipose tissue macrophages produce IL-6 and TNF-alpha; visceral adiposity correlates with hs-CRP far more strongly than BMI does. Intervention: weight loss (particularly visceral), reduced refined carbohydrate intake, time-restricted eating. A 5-10 percent reduction in body weight typically reduces hs-CRP by 30-50 percent.
• Insulin resistance. Independent of weight, elevated fasting insulin drives systemic inflammation. The CGM data covered in our CGM deep dive connects directly to this — postprandial glucose excursions drive insulin secretion, and chronically elevated insulin drives the inflammatory state. Intervention: low-glycemic dietary patterns, resistance training, sleep.
• Periodontal disease. Underrecognized as a major hs-CRP driver. Adults with untreated periodontitis often run hs-CRP 2-4 mg/L higher than they would otherwise. Intervention: dental cleaning every 3-4 months, treatment of any active periodontal pockets.
• Sleep apnea. Untreated obstructive sleep apnea elevates hs-CRP through repeated hypoxic stress and sympathetic activation. The Wisconsin Sleep Cohort and other studies show CPAP treatment reduces hs-CRP within months. Intervention: sleep study if there's any clinical suspicion (snoring, witnessed apneas, daytime fatigue, BMI above 30).
• Suboptimal sleep duration or quality. Even in adults without apnea, chronic sleep restriction (below 6 hours, or fragmented sleep) elevates hs-CRP. See the 7-hour sleep window post for the protocol.
• Chronic infections. H. pylori, chronic urinary tract infection, sinusitis, or low-grade chronic viral infections (HSV, HHV-6, CMV) can drive sustained hs-CRP elevation. Worth investigating if no other driver is identified.
• Autoimmune processes. Hashimoto's thyroiditis, early rheumatoid arthritis, inflammatory bowel disease — all elevate hs-CRP and benefit from primary disease treatment.
• Smoking and alcohol. Both elevate hs-CRP. Cessation produces measurable reduction within months.

The Lifestyle Intervention Stack — Dose-Response

For adults whose elevated hs-CRP is driven by lifestyle factors (the majority), the published intervention dose-response is well-characterized:

• Mediterranean-pattern diet — reliably lowers hs-CRP by 30-40 percent across multiple RCTs (PREDIMED, others). The polyphenol-rich, olive-oil-based, fish-forward pattern is the dietary intervention with the strongest hs-CRP data. See the Mediterranean longevity protocol.
• Time-restricted eating (16:8 or similar) — produces measurable hs-CRP reduction over 8-12 weeks, particularly in adults with baseline metabolic dysfunction. The mechanism overlaps with weight loss and improved insulin sensitivity. See the 16:8 protocol.
• Regular moderate exercise — chronically lowers hs-CRP independent of weight change. The Zone 2 + VO2 max training framework (see VO2 Max Predicts Lifespan) produces the strongest sustained hs-CRP reduction. Counterintuitively, single bouts of intense exercise produce acute hs-CRP elevation that resolves within 48 hours — don't test hs-CRP within 48 hours of an intense workout.
• Omega-3 supplementation — modestly reduces hs-CRP (typically 10-20 percent) at the standard 1-2 g daily EPA + DHA. The effect is larger in adults with low baseline Omega-3 Index. See the Omega-3 Index post.
• Vitamin D optimization — vitamin D deficiency correlates with elevated hs-CRP across observational studies. Repletion to 25-OH-D above 40 ng/mL produces modest hs-CRP reduction in deficient adults. See the vitamin D personalized dosing post.
• Sauna use — Finnish cohort data (Laukkanen) shows regular sauna use associates with lower hs-CRP and lower cardiovascular event rates. The mechanism includes heat-shock-protein-mediated reduction of chronic inflammation. See the Laukkanen sauna protocol.

The pragmatic protocol: test baseline hs-CRP (twice, separated by 2-4 weeks, in the absence of acute illness); identify the upstream driver(s) from the differential above; implement the lifestyle stack and address the upstream driver; retest at 8-12 weeks. The marker is responsive enough that retesting closes the loop tightly.

The Pharmacological Layer — When Lifestyle Isn't Enough

For adults whose hs-CRP doesn't normalize on lifestyle intervention (genetic factors, persistent autoimmune drivers, treatment-resistant metabolic syndrome), several pharmacological levers exist:

• Statins — lower hs-CRP by 20-40 percent independent of their lipid effect. The JUPITER framework supports statin use specifically in adults with elevated hs-CRP and otherwise borderline cardiovascular risk profiles.
• Metformin — modestly reduces hs-CRP in adults with insulin resistance or prediabetes, independent of glucose effect. Often off-label for longevity indications.
• Low-dose colchicine — the LoDoCo2 trial (NEJM 2020) showed 0.5 mg daily colchicine reduced cardiovascular events by 31 percent in adults with established coronary disease, with mechanism largely through anti-inflammatory hs-CRP-lowering effect. Emerging as a cardiology longevity tool.
• Canakinumab — IL-1β monoclonal antibody used in the CANTOS trial (NEJM 2017). Demonstrated that direct anti-inflammatory intervention reduces cardiovascular events even without LDL lowering. Currently too expensive and immunosuppressive for routine longevity use, but established the principle.

The pharmacological layer is clinician-directed and individual. The longevity-protocol framing: lifestyle first (it works in most cases), pharmacology when lifestyle isn't moving the marker enough, always in conversation with a physician.

How to Get hs-CRP Tested

Three points to get right when testing hs-CRP:

1. Make sure it's the "high-sensitivity" assay, not the standard CRP. Standard CRP has a detection floor around 5 mg/L — useless for chronic inflammation assessment. hs-CRP resolves to ~0.1 mg/L. The lab order specifically requires "hs-CRP" or "high-sensitivity C-reactive protein."

2. Avoid testing during or within 2 weeks of acute illness. A cold, flu, vaccination, dental work, or intense exercise within 48 hours all elevate hs-CRP transiently. Wait 2-4 weeks after any acute event before assessing chronic baseline.

3. Test at least twice. hs-CRP has meaningful intra-individual variance. A single elevated reading might reflect a sub-clinical event you don't remember. Two readings 2-4 weeks apart, both in the absence of acute illness, establish a more reliable baseline.

Three measurement paths:

Path 1: Function Health or comparable direct-to-consumer service. Function Health's panel includes hs-CRP alongside apoB, Lp(a), Omega-3 Index, homocysteine, fasting insulin, and the broader marker set (~$500 for the comprehensive annual panel, no physician order). For adults running the full longevity panel, this is the cleanest path because hs-CRP is interpreted alongside the broader biomarker context.

Path 2: Quest Direct or LabCorp OnDemand standalone hs-CRP test. Single-marker direct-to-consumer ordering. Cost: ~$20-40 for hs-CRP alone. Best for adults already running the broader panel through Function Health or their primary care, who want a low-cost retest at 8-12 weeks to confirm intervention effect.

Path 3: Request from your primary care physician. Most physicians will order hs-CRP on request. Many cardiologists are already ordering it as part of advanced lipid panels. Insurance coverage is generally good when framed around cardiovascular risk assessment.

The pragmatic measurement cadence: baseline (twice, 2-4 weeks apart) before any intervention, retest at 8-12 weeks after starting intervention, then annually as part of the broader biomarker panel.

Integration With the Broader Biomarker Stack

hs-CRP completes the Attia/Means/Dayspring cardiovascular-cognitive-inflammation panel:

• apoB — particle-count cardiovascular marker (covered in our deep dive). apoB drives particle-mediated atherosclerosis; hs-CRP modulates whether that atherosclerosis becomes clinically dangerous. The two together capture cardiovascular risk far better than either alone.
• Lp(a) — genetic cardiovascular risk marker. Adults with elevated Lp(a) particularly benefit from tight hs-CRP control as a compensation lever.
• Omega-3 Index — membrane-composition marker (covered in our deep dive). The two are mechanistically linked — adequate Omega-3 Index reduces hs-CRP, and the resolvins/protectins synthesized from EPA actively resolve the inflammatory state hs-CRP captures.
• Homocysteine — methylation cycle marker (covered in our deep dive). Elevated homocysteine and elevated hs-CRP often co-occur; both contribute to the chronic vascular and neural inflammatory state.
• Fasting insulin and HOMA-IR — metabolic markers. Insulin resistance is one of the most common upstream drivers of elevated hs-CRP; the two markers move together with most lifestyle interventions.
• Vitamin D (25-OH-D) — covered in our personalized dosing post. Vitamin D deficiency correlates with elevated hs-CRP; repletion often reduces it.

The integrated panel — apoB + Lp(a) + Omega-3 Index + homocysteine + hs-CRP + fasting insulin + vitamin D — is the cardiovascular-cognitive-inflammation framework that Attia, Means, and Dayspring operationalize. The Biomarker Testing hub at /pages/biomarker-testing compares the services that run the full panel. The full panel + the protocols for each marker live in Decode Your Biology.

The Bottom Line

hs-CRP is one of the most informative single numbers in the entire longevity biomarker panel:

• The published evidence base spans cardiovascular events (JUPITER, CANTOS, multiple cohort studies), cognitive decline (Framingham, Rotterdam, ARIC), and all-cause mortality
• The marker is responsive to lifestyle intervention within 8-12 weeks
• Testing is cheap ($20-40 standalone, or bundled into the broader panel) and widely available
• The intervention stack is mostly the same intervention stack that helps everything else — Mediterranean diet, time-restricted eating, regular exercise, sleep optimization, omega-3 adequacy
• The clinical actionability is high — elevated hs-CRP identifies upstream drivers (visceral adiposity, periodontal disease, sleep apnea, chronic infection) that are themselves modifiable

For adults running a longevity protocol — particularly the cardiovascular and cognitive longevity facets — getting hs-CRP onto the panel is one of the highest-information additions in the entire stack. The marker integrates with everything else. The intervention is mostly lifestyle. The retest closes the loop. Most adults haven't measured.

This article is part of the PureLongevity research library. Nothing here constitutes medical advice. hs-CRP interpretation in the context of autoimmune disease, recent infection, or acute injury requires physician input. Statin and other pharmacological decisions are clinician-directed. Always verify with a qualified clinician before changing a supplement or medication protocol. PureLongevityToday may earn a commission from purchases made through links in this article.