Foundations

What aging is, what measurement means, and which evidence rules should govern a longevity claim. This section gives the vocabulary that makes the rest of the field readable.

Start with Healthspan vs. Lifespan, then move into the mechanism, measurement, and evidence concepts that keep protocols from becoming guesswork. Hallmarks of Aging names the mechanism map; Biological Age and Pace of Aging name measurement frames; Hormesis explains why dose matters; Evidence Tiers keeps claims tied to what human data can actually show. Lifestyle Theater names the trap of performing visible longevity signals while neglecting the base behaviors that do the work.

Read straight through, or land on a specific entry and follow its outgoing links into later sections.