Ages-ph-04-001

For the 70-year-old marathoner, it confirms what they already know: their body is younger than their birth certificate suggests. For the 55-year-old with a PAO of +9, it offers a wake-up call – and, crucially, a measurable way to track improvement.

(hypothetical): Zhang, L., Christensen, K., Ferrucci, L., & Zhavoronkov, A. (2023). A physiological composite clock for estimating age-related decline and mortality risk. Ages , 45(4), 001–028. (Manuscript ages-ph-04-001 ) ages-ph-04-001

While not a controlled trial, this is powerful real-world evidence that biological aging is not a one-way street. | Clock / Model | Input Data | Primary Output | Predicts Mortality? | Open Access? | |---------------|------------|----------------|--------------------|---------------| | Horvath (2013) | DNA methylation (353 CpGs) | Chronological age ± 3.6 yrs | Poor | Partial | | PhenoAge (2018) | 9 clinical biomarkers | Biological age | Moderate | Yes | | GrimAge (2019) | DNAm + plasma proteins | Time-to-death | Good | Partial | | ages-ph-04-001 | 42 physiological + proteomic | PAO + 5-yr risk | Excellent (AUC 0.84) | Planned | For the 70-year-old marathoner, it confirms what they