Biological Age Clocks (Horvath, GrimAge, DunedinPACE) — Diagnostics & Biomarker Testing
Epigenetic DNA methylation-based tests that estimate biological age and pace of aging — considered among the most powerful longevity biomarkers available.
Overview
Biological age clocks are computational models trained on DNA methylation patterns across thousands of CpG sites in the genome to predict chronological age and, more importantly, biological aging pace. Steve Horvath's 2013 pan-tissue clock (Horvath clock) was the first and remains foundational. GrimAge (2019) predicts lifespan and healthspan more accurately than the original clock by incorporating plasma protein markers. DunedinPACE (2022, Duke University) measures the pace of aging rather than age itself — effectively clocking how fast you are aging at any given moment. TruDiagnostic (TruAge) and Elysium Health (Index) are the leading commercial platforms. Biological age younger than chronological age is strongly associated with reduced morbidity and mortality. These tests are now used to measure the response to longevity interventions such as caloric restriction, rapamycin, exercise, and dietary changes.
Indications
- Biological vs. chronological age estimation
- Longevity intervention response tracking
- Cardiovascular and cancer risk stratification
- Pace of aging assessment (DunedinPACE)
- Baseline establishment for personalized longevity programs
Mechanism of Action
DNA methylation at specific CpG sites changes predictably with aging — the clock identifies ~350-850 of these sites whose methylation pattern encodes age information
Dosing
| Compound | Dose | Frequency | Notes |
|---|---|---|---|
| Biological Age Test (TruDiagnostic, Elysium) | Single blood draw (dried blood spot or venipuncture) | Every 6-12 months | TruAge Complete includes Horvath, GrimAge, DunedinPACE, and telomere length; $299-499/test |
Evidence Grade
GRADE B
Safety & Contraindications
- Results require interpretation alongside clinical context — do not make treatment decisions based solely on clock results
- Clock accuracy varies by tissue type and individual; blood-based clocks reflect hematopoietic aging primarily
- Stress, recent illness, or major lifestyle changes can transiently affect methylation and clock readings
- Psychological impact of learning biological age — some patients find this anxiety-inducing
- Currently not FDA-cleared as diagnostic tests; are classified as wellness/research tools