Hallmarks of Aging
The hallmarks of aging are geroscience’s mechanism map for aging claims, not proof that any intervention extends healthy human life.
Also known as: aging hallmarks, geroscience hallmarks, molecular hallmarks of aging
The phrase comes from a 2013 Cell review by Carlos López-Otín, Maria Blasco, Linda Partridge, Manuel Serrano, and Guido Kroemer. They argued that aging biology could be organized around processes that appear during normal aging, worsen aging phenotypes when intensified, and slow or partly reverse those phenotypes when improved in models. The original list named nine hallmarks. The 2023 update expanded it to twelve. A 2025 precision-geromedicine review proposed a broader 14-hallmark frame by adding extracellular-matrix changes and psychosocial isolation.
The vocabulary is useful because it disciplines mechanism talk. It is dangerous when it becomes a shortcut from “this touches an aging pathway” to “this extends healthspan.”
What It Is
The hallmarks framework is a taxonomy aging researchers use to locate mechanisms. It maps claims about DNA damage, telomeres, epigenetic drift, protein quality control, autophagy, nutrient sensing, mitochondria, senescence, stem-cell exhaustion, intercellular signaling, inflammation, and the microbiome.
The current 2023 list is the cleanest working version:
| Hallmark | What the reader should hear |
|---|---|
| Genomic instability | DNA damage and repair burden rise with age. |
| Telomere attrition | Chromosome-end protection shortens or becomes dysfunctional in dividing cells. |
| Epigenetic alterations | Gene-regulation patterns drift with age, tissue state, and exposure history. |
| Loss of proteostasis | Protein folding, clearance, and quality control become less reliable. |
| Disabled macroautophagy | Cellular recycling of damaged components becomes less effective. |
| Deregulated nutrient-sensing | Insulin, IGF-1, mTOR, AMPK, and sirtuin signaling lose youthful regulation. |
| Mitochondrial dysfunction | Energy production, redox signaling, and mitochondrial quality control degrade. |
| Cellular senescence | Damaged cells stop dividing and can secrete inflammatory signals. |
| Stem cell exhaustion | Tissue-repair capacity declines as stem-cell pools and niches fail. |
| Altered intercellular communication | Cells, tissues, immune signals, and circulating factors coordinate less cleanly. |
| Chronic inflammation | Low-grade inflammatory signaling becomes more persistent with age. |
| Dysbiosis | Microbial communities and host-microbe signaling shift with age, diet, drugs, and disease. |
The framework does not say that aging is only these twelve processes. It says these processes are useful common denominators. Some act like primary causes, some like compensatory responses, and some like integrative results of decline. An intervention may move one part of the map without improving function, disease risk, or survival.
Why It Matters
Longevity claims often borrow authority from mechanism language. A drug “modulates mTOR.” A fasting protocol “activates autophagy.” A plasma intervention is framed through inflammation or intercellular communication. Those phrases can be accurate, but they can also make a weak claim sound stronger than it is.
Hallmark vocabulary helps separate three questions:
| Question | What it can answer | What it cannot answer alone |
|---|---|---|
| Mechanism | Which aging-related process might the intervention touch? | Whether the intervention improves human outcomes. |
| Evidence tier | What kind of proof supports the claim? | Whether the mechanism is worth targeting for a specific person. |
| Endpoint | Which outcome changed: biomarker, function, disease event, disability, or survival? | Which pathway caused the change. |
That separation is the point. A rapamycin claim can be mechanistically serious because mTOR biology sits near nutrient sensing, autophagy, proteostasis, immune tone, and inflammation. The human longevity claim is still weaker than the animal-lifespan evidence. A senolytic claim can be plausible because senescent-cell burden rises with age. That does not make every dasatinib-plus-quercetin or fisetin protocol proven for healthy adults.
The hallmarks also protect against one-marker thinking. A claim that names only telomeres, only NAD+, or only autophagy is probably too narrow. Aging biology is coupled. The map asks what else is moving.
How to Recognize It
Hallmark language usually appears when an intervention is being positioned as geroprotective. The reader sees a named pathway, a diagram, or a claim that a protocol “targets aging itself.” Translate the sentence into a narrower claim.
| Claim heard in the field | Better reading |
|---|---|
| “Targets a hallmark of aging” | Mechanistic plausibility, not human outcome proof. |
| “Activates autophagy” | A cellular-recycling signal may be involved; dose, tissue, timing, and endpoint still matter. |
| “Improves mitochondrial function” | Which measure improved, in which tissue or model, and does it predict function? |
| “Reduces senescent cells” | What marker changed, how selective was the intervention, and what harm signal was tracked? |
| “Lowers biological age” | Which model output changed, and does that model predict hard outcomes? |
The framework’s own criteria sharpen the test. A hallmark should appear during aging, aggravate aging phenotypes when experimentally intensified, and slow or partly reverse those phenotypes when experimentally improved in models. The third condition is the one most often oversold. “Improves an age-related feature in a model” is not the same as “extends healthy life in humans.”
A claim that targets a hallmark has earned the next question, not the conclusion. Ask what human endpoint changed, in whom, at what dose, and with what tradeoff.
How It Plays Out
A reader evaluating Rapamycin Off-Label Longevity Dosing should understand why the claim attracts serious attention. Rapamycin acts on mTOR, and animal studies link mTOR inhibition to lifespan effects. That does not let the reader skip the human question: off-label rapamycin has not been shown to extend healthy lifespan in adults.
A reader evaluating Therapeutic Plasma Exchange and Plasma Dilution sees a different mechanism story. Plasma dilution is often framed through inflammatory signaling, circulating factors, immune aging, proteostasis, and intercellular communication. The question remains whether a specific protocol changes clinically meaningful outcomes, not whether it can be placed on a hallmark diagram.
A reader evaluating exercise, sauna, fasting, or cold exposure should make the same move. These practices can trigger stress-response biology, mitochondrial adaptation, inflammatory changes, or autophagy-related pathways. The Hormesis question is dose and recovery. The hallmark label helps name the pathway. It does not set the dose.
Evidence
Evidence tier: Mechanistic / animal model. The hallmarks are a review-derived framework, not a randomized human intervention result. Their support comes from cell biology, animal models, genetic perturbation, tissue studies, and selected human biomarker associations.
The 2013 review gave the field a shared vocabulary by naming nine common denominators of mammalian aging (López-Otín et al., 2013). The 2023 update expanded that universe to twelve hallmarks and emphasized that the categories interact rather than operate as isolated switches (López-Otín et al., 2023).
Geroscience broadened the frame from mechanisms to disease risk. Kennedy and colleagues argued that aging biology links multiple chronic diseases rather than sitting beside them as a separate topic. That is why a mechanism map can matter clinically. It still must be tested against outcomes.
The 2025 precision-geromedicine review is the recent shift. Kroemer and colleagues presented a 14-hallmark schematic that adds extracellular-matrix changes and psychosocial isolation to the 2023 twelve-hallmark frame. The review also emphasized gerogenes, gerosuppressors, omics-based biomarkers, clinical biomarkers, digital biomarkers, psychosocial profile, and exposure history as inputs to future precision geromedicine. It leaves the stronger therapeutic claim pending randomized trials and regulatory approval.
Extracellular-matrix aging shows why the expansion is plausible. Yi and colleagues reported that elastin-derived matrix fragments can drive inflammatory and aging-like phenotypes in mice through immune activation, with intervention experiments pointing to elastin-fragment signaling as a candidate mechanism (Yi et al., 2025). That is strong mechanistic work, not a human longevity protocol.
Psychosocial isolation is different. It has strong human outcome associations, but it is not the same kind of molecular mechanism as telomere attrition or macroautophagy. If it belongs in a precision-geromedicine hallmark map, it belongs as a supracellular and behavioral risk dimension.
Caveats and Open Questions
The framework can sound cleaner than biology is. Hallmarks overlap, feed back into each other, and vary by tissue. A practice may move one marker in a favorable direction while stressing another system. A biological-age clock may summarize downstream multi-hallmark change without revealing which mechanism to target.
The number of hallmarks keeps changing. The field moved from nine in 2013 to twelve in 2023, and a 2025 geromedicine frame now argues for fourteen. That evolution is useful because the biology is still being mapped. It also means the hallmarks are not a closed periodic table.
The largest open question is translational. If a future intervention improves several hallmarks in a model, which human endpoint should carry the claim: disease incidence, disability-free survival, physical function, cognition, biological-age movement, or lifespan? Until that endpoint is specified, hallmark language remains an orientation tool.
When an article says an intervention modulates a hallmark, read that as a mechanistic statement. Then look for the evidence tier. If the tier is mechanistic or animal-model only, the claim is not ready to carry a human healthspan conclusion.
Consequences
Benefits. The hallmarks give the reader a common language across interventions that otherwise look unrelated. Rapamycin, fasting, exercise, sauna, senolytics, plasma dilution, microbiome work, and biological-age testing can all be placed on one map. That makes comparison easier without pretending the evidence is equal.
The framework also raises the burden on confident mechanism stories. If a claim invokes mTOR, autophagy, NAD+, telomeres, senescence, or inflammation, the reader can ask where the claim sits on the map, which endpoint changed, and whether Evidence Tiers supports the confidence.
Liabilities. The same vocabulary can invite Mechanism-Pumping. A confident writer can chain five hallmarks together and make almost any intervention sound profound. That does not mean the intervention works. It means the story has biological vocabulary.
The practical stance is conservative: use hallmarks to locate the mechanism, use evidence tiers to judge the claim, and use Healthspan vs. Lifespan to decide whether the claim matters.
Related Articles
Sources
- Kennedy, Brian K., Shelley L. Berger, Anne Brunet, Judith Campisi, Ana Maria Cuervo, Elissa Epel, Claudio Franceschi, et al. “Geroscience: Linking Aging to Chronic Disease.” Cell 159, no. 4 (2014): 709-713. https://doi.org/10.1016/j.cell.2014.10.039
- Kroemer, Guido, Andrea B. Maier, Ana Maria Cuervo, Vadim N. Gladyshev, Luigi Ferrucci, Vera Gorbunova, Brian K. Kennedy, Thomas A. Rando, Andrei Seluanov, Felipe Sierra, Eric Verdin, and Carlos López-Otín. “From Geroscience to Precision Geromedicine: Understanding and Managing Aging.” Cell 188, no. 8 (2025): 2043-2062. https://doi.org/10.1016/j.cell.2025.03.011
- López-Otín, Carlos, Maria A. Blasco, Linda Partridge, Manuel Serrano, and Guido Kroemer. “The Hallmarks of Aging.” Cell 153, no. 6 (2013): 1194-1217. https://doi.org/10.1016/j.cell.2013.05.039
- López-Otín, Carlos, Maria A. Blasco, Linda Partridge, Manuel Serrano, and Guido Kroemer. “Hallmarks of Aging: An Expanding Universe.” Cell 186, no. 2 (2023): 243-278. https://doi.org/10.1016/j.cell.2022.11.001
- Yi, Junzhi, Yixuan Wang, Hairu Sui, Zhichu Chen, et al. “Elastin-Derived Extracellular Matrix Fragments Drive Aging Through Innate Immune Activation.” Nature Aging 5, no. 12 (2025): 2380-2398. https://doi.org/10.1038/s43587-025-00961-8