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As an anti-aging advocate, I certainly want people to view aging as a disease or as an unhealthy syndrome – whatever label we settle on should make clear that aging is not something to passively accept. “Is aging a disease?” is a common question but not one well-formulated. More useful would be: Is it helpful to see aging as disease? In what ways is aging like a disease and in what ways does it differ? Is there more accurate and useful way of describing it?
Arguing back and forth over whether age IS a disease will lead us into philosophical debates not terribly conducive to solving real problems. It makes more sense to ask whether we should classify aging as a disease for the purpose of enabling funding and clinical trials. And, if not, how should we classify it based on both the biological issues and regulatory realities. The question extends beyond mere semantics, carrying profound implications for medical research, healthcare systems, and our fundamental conception of human healthspan.
Arguments for classifying aging as a disease
Aging has identifiable pathophysiology: Aging involves progressive biological dysfunctions mirroring disease processes like neurodegeneration or cardiovascular decline: DNA damage, telomere shortening, genomic instability, mitochondrial decline, stem cell exhaustion, epigenetic alterations, deregulated nutrient sensing, protein misfolding, cellular senescence, and altered intercellular communication.
Even if aging were universal – as it seems to be for mammals, though naked mole rats, bats, and bowhead whales show negligible senescence – that would not exclude aging from being a disease. Instead, it would mean aging is a “special form of disease” as David Gems puts it. The biological changes occurring during aging are not meaningfully different from those recognized in so-called “accelerated aging diseases” like Hutchinson-Gilford Progeria Syndrome—the only distinction being the rate of progression.
Even if aging were universal that would not exclude aging from being a disease.
It causes morbidity and mortality: Functionally, aging causes the same outcomes as diseases: reduced quality of life, increased morbidity, and mortality.
Aging meets several disease criteria: It involves progressive dysfunction, increased vulnerability to pathology, and ultimately leads to death. It has identifiable biological mechanisms including cellular senescence, DNA damage accumulation, mitochondrial dysfunction, and chronic inflammation. Like diseases, aging shows measurable biomarkers and follows somewhat predictable progression patterns.
Measurable and treatable: The processes involved in aging are measurable, and interventions (e.g., senolytics, NAD+ boosters, mTOR inhibitors) can modify them. The Geroscience Network frames these as “hallmarks of aging”, suggesting a pathological state amenable to intervention, akin to treating cancer or diabetes.
Classifying it as a disease could accelerate research: This reinforces the point that it is the classification that matters, not what aging “is” in itself. Institutions like the FDA, WHO, and ICD (International Classification of Diseases) do not classify aging as a disease, which reflects—and reinforces—resistance. This limits the creation of clinical endpoints for trials. Accepting aging as a disease would open up regulatory incentives like orphan drug designation, faster trials, and reimbursement. It would create a clinical framework for prevention and intervention trials (e.g., targeting inflammaging, frailty, epigenetic drift).
Public health effects: Aging drives the majority of global mortality (e.g., 70% of deaths in 2023 linked to age-related causes per WHO), suggesting it functions as a disease-like process warranting medical focus. Classifying it as such could prioritize research funding, currently skewed toward specific illnesses. Recognizing aging as a treatable condition would enable more efficient resource allocation using metrics like quality-adjusted life years (QALYs) and healthy-years equivalent (HYE) when evaluating research and clinical programs . The economic impact could be enormous — researchers estimate that just 2.6 additional years of healthy living could provide an $83 trillion value to the economy.
Preventive Potential: Viewing aging as a disease encourages proactive intervention (e.g., lifestyle changes, drugs like rapamycin) before symptoms manifest, paralleling preventive medicine for hypertension, which could extend healthspan and reduce healthcare costs.
There are precedents: Medical history demonstrates that what constitutes disease evolves with scientific understanding. Conditions once considered normal consequences of aging—osteoporosis, isolated systolic hypertension, sarcopenia, frailty, and senile Alzheimer’s disease—are now classified as diseases requiring medical intervention. Osteoporosis only gained official disease status from the World Health Organization in 1994, despite being nearly universal in elderly populations. Similarly, fever was once considered a disease itself rather than a symptom until medicine advanced to understand its underlying causes.
These changes in disease classification suggests aging could follow the same path as our comprehension of its mechanisms deepens. As Caplan (2005) argues, if aging serves no biological purpose but rather results from “evolutionary neglect, not evolutionary intent,” then the notion of aging as a natural process might be mistaken.
We can spot some signs of change. The World Health Organization’s recent inclusion of “ageing-associated decline in intrinsic capacity” (code MG2A) and “Ageing-related” (code XT9T) in ICD-11 represents a significant step toward medical recognition of aging’s pathological nature. While avoiding the term “disease,” these classifications acknowledge aging as a condition with functional consequences worthy of medical attention. This compromise position suggests aging is increasingly viewed as lying somewhere between a natural process and a classical disease.
Arguments against classifying aging as a disease
Aging is a normal, universal, and natural biological process: Unlike most diseases, aging affects everyone and is part of the normal life course. The naturalistic argument emphasizes that aging has been universal throughout human history, unlike diseases which represent deviations from normal function. In this view, aging is a universal, programmed outcome of evolution, not a pathological deviation. Rather than a malfunction, aging reflects trade-offs (e.g., reproductive fitness vs. longevity). While malfunctions like pneumonia have clear etiologies, aging does not.
Proponents of this argument also claim that aging lacks a clear “normal vs. abnormal” distinction, making it difficult to pathologize without redefining the concept of disease. Critics like Dr. Suresh Rattan argue that “by definition, a condition which everyone experiences cannot be a disease.” Traditional medical frameworks view diseases as deviations from normal functioning, whereas aging represents the normal trajectory of biological systems over time.
Rattan’s version of this argument strikes me as particularly unpersuasive.
Rattan’s version of this argument strikes me as particularly unpersuasive. If it cannot be a disease “by definition” then change the definition! His assertion is like arguing that slavery is morally and legally justified because slaves are defined as less than human. The problem is in the definition, not the argument for seeing aging as a disease.
Any first-year philosophy student should also be able to detect the naturalistic fallacy in action. The mere fact of the universality and “naturalness” of aging does not tell us anything about whether it is good or bad, healthy or harmful. Just because aging may be a universal (in humans) programmed outcome of evolution, that does nothing to show that it is not pathological from an individual or even species perspective. Evolution carries no moral weight. We have to take care not to slide from “natural” as “that’s just the way things have been” to “natural” as in “this is how things should be because I’m used to them being that way.”
From an evolutionary standpoint, aging is a side-effect of declining selection pressure after reproduction—it has no purpose or design.
On top of these problems, in truth aging is not universal. The argument fails due to a false premise. Organisms that show no signs of aging include bacteria and amoebas, yeast, creosote bushes, many clonal plants, and many animals show negligible senescence, such as hydra, planarian worms, some jellyfish, lobsters, Greenland sharks, rockfish, sea urchins, and Galapagos giant tortoises.
The argument would have to pull back to the point where it claims only that aging is universal among mammals. That dilutes the strength of the point. Even if aging were universal among all animals or all species, so what? A decline and growing weakness may affect everyone but that doesn’t mean it’s not bad or dysfunctional. Besides, many conditions we call diseases (like certain genetic disorders) affect entire populations, so prevalence alone shouldn’t disqualify aging.
Timothy V. Gladyshev and Vadim N. Gladyshev point out that “In medicine, whether a condition is a disease is often determined by how abnormal it is (e.g. how many standard deviations is it from the population norm?), and whether it leads to a decrement in quality of life. However, this is inherently subjective, as norms change over time as a result of accepted medical practice and personal determination for each patient. Similarly, although some scientists are currently averse to “pathologizing” aging, the development and implementation of effective anti-aging therapies may cause these attitudes to shift.”
There is no agreed-upon point at which a person becomes old: Daniel Belsky, an assistant professor at the Columbia Mailman School of Public Health, says that there is no agreed-upon point at which a person becomes old. People with the same chronological age can have widely differing biological ages based on observable changes.
It is not chronological age that is the problem, but the biological processes of aging.
But this misses the point: it is not chronological age that is the problem, but the biological processes of aging. It is not the mere passage of time that is a problem, it is the degeneration that goes with it. It is irrelevant that this degeneration goes faster in some people.
Of course there is no point at which someone becomes old. Nor is there a precise moment when day becomes night. It is a process comprised of many parts. The fact that many of these happen at different rates between individuals (and between species) does nothing to show that aging is not a set of identifiable processes nor that aging is not a problem that we should treat. Nor is there an agreed-upon point where someone becomes frail or where they are immune deficient, but there are clear cases of frailty and immune insufficiency.
It lacks a single etiology: Mechanistically, aging may be too complex and multifactorial to fit traditional disease models. It’s more like the wearing out of multiple systems simultaneously than a specific pathological process. Diseases often have specific causes (e.g., bacteria, gene mutation, autoimmunity). Aging is multifactorial and systemic—it doesn’t have a single point of failure or consistent timeline. Also, aging exhibits enormous phenotypic variability between individuals, making it difficult to define standardized diagnostic criteria. As The Lancet Diabetes & Endocrinology noted, “any treatment for aging must span a broad array of symptoms, and lumping them all together under the umbrella of ‘aging’ may be misleading.”
I grant that this is a reasonable point. I think it does give some grounds for seeing aging as something other than a disease. But it is not grounds for rejecting the idea that aging is a problematic, unhealthy condition. Rather than a disease, it might better be viewed as a pathology or a syndrome.
Medicalization of aging could be ethically fraught: This argument claims that medicalizing aging could have negative social implications, potentially devaluing older adults or creating unrealistic expectations about “curing” a natural process. One possible outcome is overmedicalization of normal aging processes.
This claim is not implausible, given our existing healthcare systems. Arguably, overmedicalization already exists with no reference to aging. We need to tackle this issue in general, not allow it to block treatment of aging.
While this specific issue deserves some attention, I reject completely the claim that seeing aging as a disease would devalue older people. We already recognize the deficits and challenges faced by older people. Seeing aging as a disease would make us, if anything, more sympathetic to them. David Sinclair is also concerned about aging but sensibly notes that the best way to combat ageism is to tackle aging: facing the problem head-on by devising treatments to slow its progress. “The current view that aging is acceptable is ageism in itself,” he says.
Kiran Rabheru, a geriatric psychiatrist at the Ottawa Hospital, cautions that legitimizing old age as a diagnosis risks inappropriate use, with physicians potentially dismissing symptoms as inevitable consequences of aging rather than investigating treatable conditions. On the contrary, it would do the opposite. Aging would be seen as something that people suffer from and deserve relief. This claim also contradicts the over-medicalization claim. Which is it? Will we over-treat aging symptoms or dismiss them?
Whenever I see the terms “commodify” and “exploit” my Marxist red flag goes up.
Another “ethical” argument sees the push to treat aging as a disease as an attempt to commodify human aging, turning all older adults into patients. These ethicists expect “exploitation” by companies marketing unproven anti-aging treatments. This argument contradicts the claim that aging symptoms would be dismissed. Frankly, whenever I see the terms “commodify” and “exploit” my Marxist red flag goes up. In reality, what these terms come to is the process of identifying needs and wants and providing solutions. No doubt many of those “solutions” will be false ones. Just as with any products, people should think critically, look to reviewers and services such as Consumerlab, and even taking note of recommendations and warnings from the FDA.
Difficulty defining success: More resistance comes in the form of complaints that we would find it hard to know what a cure for aging looks like. If aging is gradual, success would be hard to define. Of course, many diseases affect us gradually, so this is a terribly weak argument. The sensible point here relates to regulatory challenges rather than to the idea of treating aging as a disease. The FDA’s rejection stems from aging lacking a single diagnostic marker or endpoint, unlike diseases with defined criteria (e.g., blood glucose levels for diabetes).
This is not an argument for rejecting the idea of treating aging as a disease. It is an argument for developing widely accepted biomarkers of aging. Much attention is focused on this matter and plenty of progress is being made. Epigenetic clocks are a particularly promising approach but far from the only one. I will discuss this more in part 2 where I related the Hallmarks of Aging and their biomarkers to my preferred conception of aging as a syndrome.
A threat to meaning and acceptance of mortality: Some ethicists (e.g., Callahan, 1995) contend that accepting death as inevitable preserves human meaning, arguing that medicalizing aging undermines cultural acceptance of mortality, a stance reinforced by its non-disease status in current medical taxonomy.
My reply: Good! We should undermine cultural acceptance of mortality. We should shake the culture and wake it up just as some shook up past societies and undermined cultural acceptance of slavery. The claim that the inevitability of death gives meaning to life is common throughout the history of philosophy and is implicit in many of our stories. In his book, The Case Against Death, Patrick Linden refers to this ironically as the Wise View. One problem with this is that ending aging does not mean the end of death, so the argument against life extension fails immediately. There are many other problems with this claim, but that’s a topic for another day.
Most of the arguments against classifying aging as a disease are weak or completely fail. But there are one or two reasonable points. The multi-factorial nature of aging does not fit well with the standard view of diseases as distinct pathologies. There is also a challenge in defining success although that one is in the process of being resolves. Even if aging is best seen not as a disease, it is absolutely something to be treated. Is there a better way to characterize aging that will focus attention on the problem and accelerate research? I will an alternative framing in a future essay.
I had not seen the following piece before I wrote this essay. It looks at obesity as a disease and compares it to aging as a disease.
It always seems to take us longer to shift from the reactive to the proactive side of things. Take mental health, for example: for decades we had detailed classifications of what was wrong with people, but only much later did we begin defining what mental health actually looks like—giving us a positive direction to aim for. Aging may be similar: if we continue to treat it only as a collection of problems, we miss the chance to frame it as something we can understand, measure, and ultimately improve. Defining aging as a disease could be the step that pushes us to move from describing decline to actively pursuing healthspan.