A demographic perspective on longevity and healthspan: Rethinking population ageing through a positive and...

Population ageing is portrayed as a threat to the sustainability of health and welfare systems. This narrative-grounded in static chronological definitions of old age-risks overstating the burden of increasing longevity while overlooking changes in survival, health and population composition. In this article, we adopt a demographic perspective to rethink longevity and healthspan through the lens of positive demography, which reframes ageing as a structural transformation that can generate opportunities if institutions, health systems and policies adapt accordingly. Using prospective measures that define old age by remaining life expectancy (LE), we show that population ageing appears less burdensome than conventional indicators suggest (e.g., dynamic dependency ratios fluctuate around 20% compared with 40% under fixed thresholds). Nonetheless, challenges persist, including growing heterogeneity and inequalities in late-life health and care needs (with healthcare workforce demand by 2071 ranging from a 33% increase to a 16% decrease depending on morbidity trends) and a widening gap between lifespan and healthspan (LE at age 60 has risen at double the rate of healthy LE), resulting in more prolonged dependency and complex end-of-life trajectories. Prevention (primordial, primary, secondary and tertiary) and palliative care emerge as crucial but insufficiently integrated components of ageing societies' health systems. We conclude that a forward-looking demographic framework-integrating dynamic age thresholds, cohort-specific health profiles, and equitable access to care across the full continuum-is essential to align societies with realities of longer lives. Population ageing is not a problem to be solved but a context within which health systems and policies must evolve.