Longevity — Slowing Biological Ageing
Live longer in better health — what the science shows
Lifespan — how long you live — is only partly determined by your genes. Healthspan — how many of those years you spend in full physical and mental function — is highly modifiable. These are the most evidence-backed tools we have.
The 6 Factors That Most Influence How Long You Live
- VO2 max (exercise capacity) — the strongest single objective predictor of longevity. Improving from 'low' to 'above average' is associated with ~45% reduction in all-cause mortality. Train it with hard intervals.
- Muscle mass — resistance training throughout life dramatically slows age-related muscle loss (sarcopenia). Never stop lifting.
- Blood pressure control — as impactful as any pharmacological longevity intervention. See Chapter 9.
- Not smoking — the single most impactful intervention for smokers. Risk drops from the first day of stopping.
- Good sleep — consistently. Chronic poor sleep is among the strongest predictors of early death and disease.
- Healthy body weight — particularly visceral (belly) fat, which drives metabolic and cardiovascular risk.
The Build-and-Repair Cycle: Why Your Body Needs Both
Your body has two opposing systems: mTOR (build — activated by protein and resistance training) and AMPK (clean up and repair — activated by fasting and aerobic exercise). True longevity requires both.
The strategy is to cycle between them: periods of building (eating, training) and periods of repair (TRE, Zone 2 exercise). Neither extreme — all fasting or all eating — is optimal.
Emerging Longevity Interventions Worth Knowing About
- NMN / NR: raise NAD+ levels reliably in humans. NAD+ drives cellular repair processes. Whether this translates to measurable lifespan benefits in healthy people is still being researched.
- Rapamycin: the most robust longevity drug in animal studies — extends lifespan significantly in mice. Some longevity physicians are prescribing it off-label. Human longevity data remains incomplete. Not for self-prescription — side effects include immune suppression.
- Metformin: a diabetes drug associated with reduced cancer and cardiovascular mortality in observational data. May partially blunt exercise adaptations. Being studied in large longevity trials.
- Peptides (BPC-157, TB-500): synthetic compounds studied for tissue repair, gut healing, and anti-inflammation. Widely discussed in longevity communities but largely unregulated and without robust human trial data. Proceed with extreme caution and physician guidance only.
The honest longevity hierarchy
No supplement or intervention compensates for: smoking, chronic sleep deprivation, sedentary behaviour, obesity, or chronic unmanaged stress. Get the basics right first. The exotic stuff is at the margin.
Bryan Johnson's Blueprint Protocol — What's Useful, What's Extreme
Bryan Johnson is a tech entrepreneur who spends ~$2 million per year attempting to reverse his biological age under physician supervision. He is not a scientist, and the $2M scale — a 100+ supplement stack, daily extensive testing — isn't the takeaway for anyone outside that budget.
- The genuinely useful principle underneath it: know your numbers, then target what's actually low. Rigorous, regular self-measurement — bloodwork, tracking trends over time, adjusting based on data rather than guesswork — is something anyone can adopt at a fraction of the cost, with a handful of well-chosen supplements instead of a hundred.
- His underlying habits are also unremarkable by design: consistent sleep schedule, no alcohol, minimal processed food, daily Zone 2 and resistance training. None of that requires his budget.
Key Takeaway
VO2 max, muscle mass, blood pressure, no smoking, good sleep, healthy weight — these six factors determine the majority of longevity. The exotic interventions are at the margin.
Connections
Exercise & Recovery
VO2 max is the strongest single predictor of longevity — hard intervals are the most efficient way to improve it.
Sleep
Chronic poor sleep is among the strongest predictors of early death and disease — the basics matter most.
Psychology, Habits & Human Connection
Blue Zone research consistently identifies purpose and belonging as longevity factors — beyond any supplement or protocol.