Inflammaging is the term Claudio Franceschi coined in 2000 for a peculiar feature of growing old: a chronic, low-grade, systemic inflammation that builds quietly over decades without an obvious infection to explain it. It is not the dramatic acute inflammation of a sprained ankle or a flu — it is a persistent hum of cytokines, immune activation, and tissue irritation that correlates with frailty, cardiovascular disease, dementia, sarcopenia, and mortality more strongly than almost any other biomarker of biological age.
This article unpacks what inflammaging actually is, how senescent cells and the NLRP3 inflammasome generate it, what trials like CANTOS revealed by accident, and which senolytics, peptides, and lifestyle interventions credibly address it.
What Is Inflammaging?
Franceschi et al. 2000 (Annals of the New York Academy of Sciences) defined inflammaging as "a chronic, low-grade, sterile, systemic inflammation that develops with advanced age." It is "sterile" because it occurs without active infection — the immune system is reacting to endogenous damage signals rather than pathogens.
The López-Otín 2013 hallmarks paper listed "altered intercellular communication" as a hallmark and explicitly called out inflammation as a key mechanism. The 2023 update promoted "chronic inflammation" to a standalone primary hallmark, recognizing the weight of evidence that it is not just downstream noise but an active driver of aging biology.
The signature of inflammaging includes:
- Elevated circulating cytokines: IL-6, TNF-α, CRP, IL-1β, IL-18.
- Skewed immune cell ratios: more myeloid cells, fewer naive T cells.
- Activated innate immune sensors: especially NLRP3, cGAS-STING, and TLRs.
- Reduced adaptive immunity: thymic involution, vaccine non-response.
The Molecular Biology
Several molecular sources feed inflammaging in parallel.
The NLRP3 inflammasome. NLRP3 is a cytoplasmic sensor that assembles into a large complex when it detects danger signals — uric acid crystals, cholesterol crystals, mtDNA, oxidized LDL, amyloid fibrils, even high glucose. Once assembled, it activates caspase-1, which cleaves pro-IL-1β and pro-IL-18 into their active forms and triggers pyroptosis. Aged tissues are richer in all of NLRP3's triggers, so the inflammasome fires more often.
The senescence-associated secretory phenotype (SASP). Senescent cells, which accumulate with age, secrete a cocktail of inflammatory cytokines, chemokines, proteases, and growth factors. The SASP is one of the largest single contributors to inflammaging, which is why senolytics — drugs that selectively kill senescent cells — have anti-inflammatory effects.
Mitochondrial damage. Damaged mitochondria leak mtDNA into the cytoplasm, where cGAS-STING reads it as a viral signal and triggers type I interferons.
Persistent latent infections. Cytomegalovirus (CMV) is the classic example. By age 60, most adults are CMV-positive, and CMV-driven T cell expansion is associated with worse immunosenescence and higher inflammatory markers.
Gut microbiome shifts. Aging is associated with reduced microbial diversity, increased gut barrier permeability, and elevated systemic LPS — sometimes called "leaky gut" — which keeps innate immune sensors mildly activated.
Adipose tissue inflammation. Visceral fat is a major IL-6 source, and visceral fat increases with age even when total body fat stays constant.
How Chronic Inflammation Drives Aging
Inflammaging is increasingly viewed as one of the most actionable hallmarks because it sits at a junction where damage from many sources converges into a common harmful output.
- Cardiovascular disease. Atherosclerosis is fundamentally an inflammatory process. IL-6 and CRP predict events independently of cholesterol.
- Neurodegeneration. Microglial activation drives Alzheimer's progression. Elevated peripheral inflammation predicts cognitive decline.
- Sarcopenia and frailty. TNF-α and IL-6 promote muscle protein breakdown and impair satellite cell function.
- Cancer. Chronic inflammation creates tumor-permissive environments.
- Metabolic disease. Inflammatory cytokines impair insulin signaling.
The relationship is bidirectional — aging produces inflammation, and inflammation accelerates aging.
The Evidence
- Franceschi et al. 2000 established inflammaging as a concept.
- Wei et al. 2024 (Nature Aging) and many earlier studies show IL-6 is one of the strongest single-protein predictors of all-cause mortality in older adults.
- Coppé et al. 2008 (PLoS Biology) — Campisi lab. Defined the SASP and its inflammatory contribution.
- Baker et al. 2011 and 2016 (Nature). Clearance of p16-positive senescent cells in mice improved healthspan and reduced age-related pathologies.
- Ridker et al. 2017 (New England Journal of Medicine) — CANTOS trial. Treated 10,061 post-MI patients with stable elevated CRP using canakinumab (an IL-1β monoclonal antibody). The primary cardiovascular endpoint was met. A surprising secondary signal: lung cancer incidence and mortality were significantly reduced in the canakinumab arm. This was the first large RCT showing that simply lowering inflammation — without touching cholesterol — reduced cardiovascular events and unexpectedly benefited cancer outcomes.
- Furman et al. 2017 (Nature Medicine) linked NLRP3 activation to cardiovascular aging and cognitive decline.
- Yousefzadeh et al. 2021 (Nature) showed that aged immune cells alone are sufficient to accelerate aging in young mice.
Interventions That Target It
Senolytics. Dasatinib + quercetin (D+Q), fisetin, and navitoclax selectively eliminate senescent cells, reducing SASP-driven inflammation. Hickson et al. 2019 (EBioMedicine) showed D+Q reduced senescent cell burden in diabetic kidney disease. Our senolytics article covers the evidence in detail.
NAD+ raising. NMN and NR support sirtuin activity, which has anti-inflammatory effects in some models. Evidence is suggestive but not definitive.
Metformin. Beyond glycemic control, metformin has anti-inflammatory effects through AMPK activation and NLRP3 inhibition. The TAME trial is testing it as a healthspan intervention.
Omega-3 fatty acids. EPA and DHA shift eicosanoid biology toward resolving rather than initiating inflammation. The REDUCE-IT trial showed icosapent ethyl reduced cardiovascular events.
Exercise. Acutely inflammatory but chronically anti-inflammatory. Regular exercise lowers basal IL-6, TNF-α, and CRP.
Dietary patterns. Mediterranean diets, high fiber intake, and moderate calorie restriction lower inflammatory markers.
Canakinumab. The CANTOS trial proved IL-1β blockade reduces events. It is not used for aging because of cost and infection risk, but it validated the inflammation-targeting paradigm.
Colchicine. The LoDoCo2 trial showed low-dose colchicine reduced cardiovascular events in stable coronary disease, providing a cheaper anti-inflammatory option.
Connection to Gene Editing and Peptides
Gene editing approaches to inflammaging are mostly indirect. CRISPR screens have mapped the SASP regulatory network and identified druggable nodes. AAV-delivered anti-inflammatory cytokines (like IL-10) are in development for chronic inflammatory conditions. CAR-T cells engineered to recognize uPAR — a senescent cell surface marker — have shown the ability to clear senescent cells in mouse models (Amor et al. 2020 Nature), opening a "living drug" approach to inflammaging.
On the peptide side, several signaling peptides have anti-inflammatory profiles. Thymosin α-1 modulates immune balance. BPC-157 has anti-inflammatory effects in animal models. KPV (a melanocortin fragment) reduces NF-κB activation. None have rigorous Phase 3 aging-specific data. For more, see our longevity peptides guide.
GLP-1 receptor agonists like semaglutide also have anti-inflammatory effects independent of glucose lowering, which may contribute to their cardiovascular benefits.
What's Still Unknown
- Specificity versus breadth. Should we target one cytokine (IL-6, IL-1β), one upstream trigger (NLRP3), or the broader senescent cell pool?
- Infection trade-offs. Suppressing inflammation increases infection risk, as CANTOS showed. Finding the sweet spot is hard.
- Causation versus correlation. IL-6 predicts mortality, but is it driving deaths or just marking sick patients?
- Source identification. How much inflammaging comes from senescent cells, gut, fat, mitochondria, or CMV — and can we attribute and target each independently?
- Diet specifics. Which specific foods or compounds reliably move inflammatory markers in healthy older adults?
FAQ
Is inflammaging the same as autoimmune disease?
No. Autoimmune disease involves specific adaptive immune attack on self-tissue. Inflammaging is a low-grade, sterile, mostly innate immune phenomenon driven by damage signals.
Does CRP measure inflammaging?
Partially. CRP is a useful marker of inflammation but is acutely responsive to many things. IL-6, fibrinogen, and GlycA are complementary measures.
Can lowering inflammation extend lifespan?
In mice, removing senescent cells extends healthspan and lifespan. In humans, the CANTOS trial showed reduced events from IL-1β blockade. Direct lifespan trials in humans are not yet feasible.
Are senolytics safe for healthy people?
Not yet established. Trials so far have been in specific disease contexts. Long-term safety in healthy aging adults is unknown.
Should I take fish oil for inflammaging?
EPA/DHA reduce inflammatory markers and have a favorable safety profile. The clinical evidence is mixed but supportive in cardiovascular contexts.
What lifestyle change has the biggest impact on inflammaging?
Probably regular moderate exercise combined with not being overweight. Both move inflammatory markers more reliably than any current supplement.
