How aging causes age-related diseases

Usually, aging is vaguely defined either by a collection of phenotypic traits or by general, abstract and hardly applicable definitions such as “the accumulation of structural damage to cells with time”. This hinders research on the measurement of biological aging (what exactly should be measured?), on antiaging interventions (what exactly should they target?), and the very definition of geroscience (what is exactly the process that is supposed to cause many age-related diseases upstream of their occurrence, yet be distinct from them?). We work on a precise definition of what the mechanisms of aging are, in relation to their causing age-related diseases. We make the hypothesis that aging in a multicellular organism is better defined as the progressive degradation of the repair and maintenance mechanisms that play a role in tissue homeostasis by compensating for the degradation of primary cells and extracellular structures. We also try to clarify related issues regarding the measurement of aging, the definition of an anti-aging intervention, and the soundness of a geroscience strategy to age-related diseases.