Feb 9, 2026Epigenetic Clocks and Biological Age: Horvath, GrimAge, DunedinPACE — What They MeasureEpigenetic clocks measure DNA methylation patterns that change predictably with age. Different clocks predict different endpoints — Horvath measures biological age, GrimAge predicts mortality, DunedinPACE measures aging speed. Understanding what they do and don't measure is essential before acting on results.