Aging & longevity
How old you really are — and how fast you're aging. The bedrock metric and the twelve mechanisms beneath it.
DNA-methylation clocks read patterns in your DNA to calculate biological age. Horvath predicts chronological age; PhenoAge tracks disease phenotype; GrimAge is the most mortality-predictive; and DunedinPACE is the speedometer — it measures your rate of aging, not your age. Bryan Johnson's ~0.69 means he ages ~8 months per 12. TruDiagnostic's TruAge runs every clock from one blood draw; SYMPHONYAge breaks the result down per organ system, so we can see which modalities move which organs. The challenge is latency — epigenetic tests run only every 3–6 months, so we build a daily proxy from HRV, resting HR, sleep consistency and VO₂max, calibrated against the quarterly ground truth.
The four aging clocks
| Clock | What it reads | Best for |
|---|---|---|
| Horvath | DNA methylation across tissues | The original chronological-age clock |
| PhenoAge | Methylation tuned to disease phenotype | Morbidity & mortality risk |
| GrimAge | Methylation + plasma protein surrogates | The most mortality-predictive |
| DunedinPACE | Rate of methylation change | The speedometer — pace of aging |
DunedinPACE — the speedometer
Most clocks tell you how old your body looks; DunedinPACE tells you how fast it is aging right now. Bryan Johnson's ~0.69 means his body ages roughly 8 months for every 12 calendar months. A value under 0.80 is the headline number the app exists to move — and the one a 90-day Arete membership is designed to shift.
SYMPHONYAge — a biological age per organ
| Organ system | Primary Arete lever |
|---|---|
| Cardiovascular | Infrared sauna — heat as a cardiovascular stressor |
| Metabolic & immune | Cold exposure — brown fat, anti-inflammatory shift |
| Musculoskeletal | The fitness floor — load and progressive overload |
| Brain | Sleep architecture + breathwork |
Telomeres — the proof-of-rejuvenation number
Telomeres are the protective caps on chromosomes that shorten with each cell division. Johnson reported a 2.6% telomere extension (10.3 → 11.4 kb) after his HBOT protocol, with telomerase activity comparable to a 12-year-old. Tested bi-annually, it is one of the most legible 'younger than last time' numbers a member can receive.
The latency problem — bridging the gap with daily proxies
Epigenetic tests can only run every 3–6 months. The R&D work is the calibration study: build a daily biological-age proxy from continuous signals — HRV trend, resting heart rate, sleep consistency and VO₂max trajectory — and tune the weighting against real TruAge results until the proxy tracks the ground truth. The weighting isn't uniform: sleep and HRV dominate for sedentary members; VO₂max and RHR for athletes who already sleep well.
PhenoAge from a standard panel — the middle tier
Between the daily proxy and the bi-annual epigenetic test sits a measure most protocols overlook. PhenoAge can be computed from nine standard blood markers — albumin, creatinine, glucose, hsCRP, lymphocyte %, mean cell volume, red-cell distribution width, alkaline phosphatase and white-blood-cell count. Every member doing the quarterly panel gets a PhenoAge reading at no extra cost; its trajectory becomes a meaningful intermediate outcome.
The initiating causes of cellular damage — they happen first.
- 01Genomic instability
- 02Telomere attrition
- 03Epigenetic alterations
- 04Loss of proteostasis
The body's responses to damage — protective at first, harmful when chronic.
- 05Disabled macroautophagy
- 06Deregulated nutrient sensing
- 07Mitochondrial dysfunction
- 08Cellular senescence
The downstream consequences that produce the tissue dysfunction of aging.
- 09Stem-cell exhaustion
- 10Altered intercellular communication
- 11Chronic inflammation (inflammaging)primary target
- 12Dysbiosis