Bryan Johnson's protocol is based on the concept that each organ ages at its own rate. Identifying an organ's accelerated biological age—like his "64-year-old ear"—allows for targeted interventions that can slow overall aging and prevent related issues like cognitive decline.

Aging isn't uniform. Your heart might age faster than your brain, predisposing you to cardiovascular disease over Alzheimer's. Quantifying these organ-specific aging rates offers a more precise diagnostic tool than a single 'biological age' and explains why people succumb to different age-related illnesses.

Contrary to the idea of a slow, steady decline, large-scale blood protein analysis shows aging happens in distinct waves. These are periods of dramatic, coordinated molecular changes. The first significant "wave" of aging-related changes occurs for both men and women around age 35.

A medical procedure called therapeutic plasma exchange, where a person's plasma is removed and replaced with albumin, shows anti-aging potential. In small placebo-controlled trials, this process led to epigenetic markers indicating that some organs and the body overall looked biologically younger.

The physical decline, decreased mobility, and frailty common in the elderly, even without a specific diagnosed disease, can be directly attributed to the accumulation of senescent cells. This links a macro-level health observation to a specific cellular process, identifying a tangible target for therapeutic intervention against age-related weakness.

The distinction between "diseases of late life" and aging itself is artificial. Conditions like Alzheimer's or most cancers are simply aspects of aging that have been given disease-like names. This unifies them as targets for a single, comprehensive anti-aging medical intervention.

The composition of proteins in blood changes so dramatically with age that it can accurately predict a person's age. Crucially, these blood-borne factors are not just passive markers; they actively influence how cells and organs function, acting as a form of internal medicine.

By auditing the "noise" or corruption in a cell's epigenetic settings, scientists can determine a biological age. This "epigenetic clock" is a better indicator of true health than birth date, revealing that a 40-year-old could have the biology of a 30-year-old.

Chronic illnesses like cancer, heart disease, and Alzheimer's typically develop over two decades before symptoms appear. This long "runway" is a massive, underutilized opportunity to identify high-risk individuals and intervene, yet medicine typically focuses on treatment only after a disease is established.