Volter Longo has some interesting new ideas regarding how we look at life expectancy, lifespan. He recommends thinking about spans in terms of youthspan (peak health 20-60) and Healthspan (oriented to disease free stage and the older phase (65-120).
check – Longo VD. Programmed longevity, youthspan, and juventology. Aging Cell. 2019;18:e12843. https://doi.org/10.1111/acel.12843
also check David Sinclair’s new book Lifespan: Why We Age―and Why We Don’t Have To — is a really great book! Highly recommended …. packed with information … some should be taken with a grain of salt or maybe with a Sirtuin activator like NMN 🙂