Longevity: recurring hype vs. evidence

Thesis

“For 2,400 years patients have believed that doctors were doing them good; for 2,300 of those years they were wrong” (David Wootton, Bad Medicine: Doctors Doing Harm Since Hippocrates, Oxford University Press, 2006, p. 2). The current high-net-worth obsession with longevity is the contemporary chapter of that 2,300-year sequence, not a novelty. The structural pattern (charismatic practitioner, exclusive access, vague or surrogate mechanism, financial conflict, eventual disconfirmation) reproduces almost exactly across the centuries. What is genuinely new today is real molecular understanding of senescence. What has not changed is the incentive to package speculative interventions as exclusive ones, and the gap between what gets sold and what actually extends life.

Part 1: the historical pattern (18th century to mid-20th century)

Eighteenth century: regimens and locations. Luigi Cornaro’s calorie-restriction treatise remained canonical; German aristocracy followed Hufeland’s Macrobiotics (1797). The institutional innovation was the spa town (Bath, Baden-Baden, Spa, Carlsbad). “Taking the waters” served as hygienic theatre and social positioning. Bloodletting and purging were standard. Mesmer’s animal magnetism captivated the French court in the 1780s and was debunked by a 1784 royal commission (Franklin, Lavoisier); the commission’s report barely dented its popularity.

The Perkins Tractors, patented in the United States in 1796 (Patent No. 18, granted to Elisha Perkins of Plainfield, Connecticut) and sold in Bath and London at five guineas per pair, were the first patented elite-medical device of the industrial era. John Haygarth disconfirmed them in January 1799 by carving wooden imitations that worked as well as the real ones; the experiment is the founding placebo-controlled clinical trial in the modern Anglophone literature. The tractors faded by 1810. See Perkins Tractors and their disconfirmation by Haygarth.

Nineteenth century: industrialized spas, then the first injection. Marienbad, Vichy, Baden-Baden became annual aristocratic destinations. Hydrotherapy, homeopathy, and Weir Mitchell “rest cures” were fashionable. The pivotal moment: Brown-Séquard’s 1889 self-injection of animal testicular extract with public rejuvenation claims. This is the direct conceptual ancestor of modern TRT and peptide protocols. Metchnikoff’s Bulgarian-yogurt theory (1907) launched the probiotic genre.

Early twentieth century: the intervention era. Voronoff grafted chimpanzee testicle slices onto wealthy men in 1920s Paris, an estimated 1,000 to 2,000 procedures worldwide between 1920 and the late 1930s. Steinach promoted vasectomy as rejuvenation (Yeats, 1934). Paul Niehans opened Clinique La Prairie (1931) and injected fetal sheep cells into Pius XII, Adenauer, Chaplin; the direct ancestor of contemporary stem-cell tourism. The clinic still operates. Radium tonics were sold until Eben Byers’s jaw disintegrated in 1932.

Structural takeaway. Nearly all genuine life-extension of the period came from work the wealthy were not paying for: sanitation, vaccination, antibiotics, refrigeration. The interventions they paid for ranged from useless to fatal.

Part 2: current high-hype, low-evidence tier (worst hype-to-evidence ratio first)

NAD+ precursors (NMN, NR). Largest commercial longevity category, anchored by Sinclair-adjacent marketing. NMN reliably raises blood NAD+ in humans, but no trial shows it extends life, healthspan, or any hard endpoint. FDA reclassified NMN out of supplement status (2022). Mouse-to-human translation is weak. Documented financial conflicts. Modern “tonic” tier.

Peptides (BPC-157, epitalon, TB-500, GHK-Cu, MOTS-c, thymosin-α1). Sold via compounding pharmacies and grey-market “research use only” channels. Evidence is cell culture, small Soviet-era work (epitalon), or single-arm tolerability pilots. FDA flags most as bulk-substance safety concerns; none FDA-approved for human use. Interesting biology, essentially no clinical case.

Stem cell tourism (Panama, Bahamas, Mexico, Colombia; increasingly Cyprus, Dubai). Direct lineage from Voronoff and Niehans. Allogeneic MSCs from cord blood or adipose. No high-quality RCT for any aging indication. Real safety signals (tumours, emboli).

Plasma exchange (TPE) and IVIG. Marquee citation is the Buck Institute / Circulate Health trial (Aging Cell, May 2025): 42 healthy adults over 50, four arms, single-blind, six sessions over approximately three months. The biweekly TPE+IVIG arm showed a 2.61-year average reduction in biological age across a panel of 35 epigenetic clocks (FDR=6.22e-05); the monthly TPE arm showed 1.32 years (FDR=2.42e-02). Caveats: small N, single-blind rather than double-blind, surrogate endpoint, and the commercializing company funded the study. “Young plasma” specifically (Ambrosia successors) carries an active FDA consumer warning.

Full-body MRI screening (Prenuvo, Ezra, Neko Health). No RCT shows mortality benefit. High incidentaloma and false-positive rates drive downstream biopsies, anxiety, and repeat-scan revenue. Not endorsed for asymptomatic screening by USPSTF or major societies.

Epigenetic age clocks (TruDiagnostic, GlycanAge, Horvath-derived). High test-retest noise; clocks disagree; validated against chronological age, not individual mortality. Moving the number does not equal extending life. Repeat-testing model exploits the confusion.

Hyperbaric oxygen, methylene blue, mitochondrial stacks. Mechanistic stories, no human longevity data. HBOT-for-aging rests on one small unreplicated telomere study.

Part 3: middle tier — plausible mechanism, premature for humans

Rapamycin. Best mechanistic case (mTOR inhibition extends lifespan across all model organisms tested). PEARL (2022) and Oxford 2025 immune-aging work are suggestive on surrogates. A September 2025 Aging-US review concluded human evidence is “insufficient to affirm or negate” longevity benefits; no trial has shown lifespan extension or clear slowing of aging. Real side-effect profile; dosing is guesswork.

Senolytics (dasatinib+quercetin, fisetin). Strong Mayo Clinic preclinical work; human data limited to small pilots. Sold ahead of phase 3 evidence.

Metformin. TAME trial “imminent” since 2015. Key observational support is confounded. Newer evidence suggests metformin blunts exercise adaptation, a possible net negative in already-active populations.

Part 4: structural critique

The endpoint problem is the entire game. Wootton’s operational definition is the bar: an intervention that performs no better than placebo, while displacing no-treatment or a more effective alternative, does net harm (Bad Medicine, p. 68). The contemporary longevity industry has not cleared this bar on hard endpoints for any of its high-hype interventions. Mortality and disease-incidence trials take decades, so the industry has converged on biological-age estimates (epigenetic clocks, glycan clocks, multi-omic scores) as primary outcomes. These are not validated as causal mediators of mortality at the individual level. Almost every claim is graded against this surrogate.

Conflict of interest is the default structure. Nearly every high-hype intervention is sold by clinics or brands whose principals or investors would be financially impaired by a null result. The “scientist-CEO with a clinical trial” model reliably produces favourable surrogate-endpoint papers, not reliable evidence. The pattern is visible at every node of the lineage this archive documents: Perkins (patent-holder, sole authorized manufacturer, and license-fee recipient through the Perkinean Institution in Leicester Square), Brown-Séquard (developer, author, and self-patient), Voronoff (developer, vendor, and owner of the chimpanzee colony), Niehans (clinic operator, sole administering physician, and Pontifical Academy credential holder), and the contemporary Buck Institute / Circulate Health relationship (research institute, affiliated company, and PI-as-company-member trial team). The substance of the conflict updates with the technology of each era; the structure does not.

Part 5: what actually has human mortality evidence

Unchanged and largely unmonetizable as a luxury good: not smoking, avoiding obesity, VO2max and strength preservation, sleep, blood-pressure and lipid control, vaccination, and GLP-1s in the appropriate (obese, cardiometabolic) population. This asymmetry, durable evidence sitting in cheap unglamorous interventions, is most of the explanation for what gets hyped instead.

Wootton’s closing accounting puts the misallocation in scale. “If one thinks of the vast investment in research laboratories, hospitals, drug companies, and general practitioners dedicated to increasing life expectancy in the period between 1950 and 1980, it is striking that the result was at best only equivalent to the conquest of smallpox twice over” (Bad Medicine, p. 275). The contemporary elite-longevity market is the same misallocation continued, with smaller institutions, higher per-patient cost, and a redirected target population.

Source notes

Current-state claims (TPE trial figures, rapamycin review conclusion, FDA peptide and young-plasma warnings, NMN reclassification) draw from 2025 and 2026 sources including Aging Cell (Buck Institute/Circulate Health, May 2025), Aging-US (September 2025 off-label rapamycin review), Buck Institute and Atria Health summaries, and FDA guidance. Historical material is general medical history; the specific cases are documented in the linked archive entries above. Surrogate-endpoint and conflict-of-interest assessments are analytical, not sourced claims.