Too well to die; too ill to live: an update on the lifespan versus health span debate.

Since the dawn of human civilisation, the pursuit of immortality has been a perennial quest. Over the past century, unprecedented advancements in medical science, public health initiatives, and social policies have significantly increased the global human lifespan. The debate between lifespan (the total number of years a person lives) and health span (the period of life free from chronic disease or disability) has gained considerable attention in both scientific and public discourse, with global focus now gradually shifting from merely living longer to living better. With this increase, a critical question has emerged: are these additional years truly spent in good health? As the global elderly population projected to reach 2.1 billion by 2050, this demographic shift is expected to place a substantial burden on health care systems, economic structures, and social frameworks. Emerging research in epigenetics, regenerative medicine, and lifestyle medicine suggests that preventive measures and personalised interventions can compress morbidity, promote healthier ageing trajectories, and ultimately increase health span. We review current lifespan and health span frameworks to foster dialogue among basic scientists, clinical specialists, social scientists, public health experts, and policymakers, advocating for a balanced approach that prioritises extending healthy, functional years of life over simply increasing lifespan.