The question of whether aging is a natural, inevitable process or a medical condition subject to intervention is one of the most significant debates in modern biological science. For centuries, the gradual decline associated with growing older has been accepted as a universal fate, distinct from pathology. Recent advances in geroscience—the study of the biology of aging—have challenged this traditional view. The core of the debate centers on whether the molecular and cellular changes that drive age-related decline should be reclassified. This reclassification carries profound implications for drug development, healthcare funding, and the very definition of human health.
How Science Defines Aging and Disease
Biological aging, or senescence, is defined as the time-related deterioration of the physiological functions needed for survival and fertility. It is characterized by the accumulation of molecular and cellular damage over time. This damage leads to a gradual decrease in physical and mental capacity, ultimately increasing the risk of disease and death. The process is universal, affecting all members of a species that live long enough.
Disease is medically defined as an abnormality of bodily structure or function that impairs normal activity. Many researchers argue that aging fits this definition because it is a “harmful abnormality of bodily structure and function” with recognizable signs and symptoms at the cellular level. The line between the two concepts is blurred because aging is the single largest risk factor for nearly every chronic disease, including cancer, Alzheimer’s disease, and cardiovascular disease. If a condition causes widespread functional decline and increases susceptibility to numerous pathologies, some argue it should be considered a disease in its own right.
The Current Regulatory Stance on Aging
Globally, major regulatory bodies currently stop short of classifying aging itself as a disease. The U.S. Food and Drug Administration (FDA) views aging as a natural biological process, not a disease. This perspective means that drugs must target a specific, recognized age-related disease, such as heart failure or diabetes, rather than attempting to treat the underlying aging process itself. The FDA’s stance creates a significant barrier for approving therapies designed to slow or reverse generalized aging.
The World Health Organization (WHO) also does not classify aging as a disease in its International Classification of Diseases (ICD-11) system. While an initial proposal to include “old age” was withdrawn, the WHO adopted the term “ageing-associated decline in intrinsic capacity” (MG2A). This code is listed under “General Symptoms” and highlights the functional effects of aging without explicitly labeling the process itself as a disease. Additionally, the ICD-11 includes an extension code, XT9T, which allows for the targeting of “Ageing-related” issues as a contributing cause or risk factor for other diseases.
Why Advocates Seek Disease Classification
A primary argument for classifying aging as a disease is the potential for unlocking significant research and development funding. Current funding mechanisms, such as those from the National Institutes of Health (NIH), are typically structured to address specific, coded diseases. If aging were recognized as a disease, it would legitimize and stimulate massive government and private investment into geroscience research that currently struggles to secure grants under the umbrella of “normal” aging.
Advocates also believe that treating aging as a disease allows researchers to target the fundamental biological mechanisms of decline, often referred to as the “hallmarks of aging.” These mechanisms include cellular senescence, genomic instability, and mitochondrial dysfunction. By addressing these root causes, scientists aim to prevent multiple age-related diseases simultaneously, rather than treating individual, downstream conditions as they appear.
Disease classification would also acknowledge that aging is a treatable process, encouraging the development of preventative interventions. Currently, a healthy individual showing signs of biological aging cannot be prescribed a drug to slow that process because there is no disease indication to treat. Reclassification would provide the necessary framework for developing and testing geroscience interventions, or “geroprotectors,” aimed at extending the period of healthy life, known as healthspan. The goal is to compress the period of frailty and illness at the end of life, allowing people to remain healthy for longer.
Objections to Treating Aging as a Pathology
One of the most profound objections to classifying aging as a disease is the concern about the medicalization of a universal human experience. Critics argue that pathologizing a natural process risks stigmatizing older adults and reinforcing ageism in healthcare settings. If aging is labeled a disease, it may lead doctors to dismiss genuine symptoms in older patients as simply a normal part of their “disease,” potentially resulting in missed diagnoses.
Concerns also exist regarding the allocation of finite healthcare resources. Classifying a condition that affects every human being as a disease could divert vast amounts of money and personnel away from acute illnesses and rare diseases. The difficulty in defining a successful treatment for aging is another philosophical hurdle, as aging is a continuous process rather than an endpoint. The risk is that the healthcare system could become overwhelmed by the universal need for expensive anti-aging treatments.
A separate objection focuses on potential societal and economic pressures. If anti-aging treatments become medically necessary, there is a risk of creating a two-tiered system where only the wealthy can afford to slow their aging process, exacerbating social inequality. Furthermore, insurance companies could eventually mandate or penalize individuals for not pursuing expensive preventative treatments, shifting the burden of a universal biological process onto the individual.
Practical Consequences of Defining Aging as a Disease
If regulatory bodies like the FDA were to recognize aging as a disease, the most immediate practical consequence would be a revolution in the drug development pipeline. Currently, drug trials for potential geroprotectors must select a specific age-related disease as their primary endpoint, which is a complex and time-consuming process. A disease classification would allow clinical trials to use endpoints related directly to the rate of biological aging, such as changes in validated biomarkers or measures of functional decline. This regulatory shift would simplify the path to market for drugs designed to target the foundational mechanisms of aging.
The second major consequence would involve a significant shift in insurance coverage and patient access. Treatments currently categorized as elective, cosmetic, or wellness-related would potentially transition into medically necessary care. Once a condition is recognized as a disease, health insurance providers are more likely to cover the costs of interventions. This would democratize access to therapies that slow or reverse the aging process, integrating longevity research fully into the established healthcare system.