Epigenetic clocks measure biological resilience, not just time—making them better predictors of functional decline than chronological age

DNA methylation clocks are celebrated for estimating age. But their real power is different: they measure the loss of biological resilience that precedes clinical disease.

The hypothesis: epigenetic clocks work because they capture system-wide entropy accumulation—loss of regulatory precision that manifests first as reduced stress tolerance, then as overt dysfunction. A 70-year-old with a clock age of 60 is biologically younger not because they have less damage, but because they maintain better system coordination.