Epigenetic clocks: advancing biological age measures towards meaningful clinical use

The distinction between chronological and biological age has become central to modern ageing research. Although chronological age simply counts time, biological age aims to capture the molecular, physiological, and environmental changes that shape frailty and disease vulnerability. Public interest in biological age has grown rapidly; yet, important questions remain about the reliability of these measures in commercial wellness settings and how they should be used in clinical practice. Measuring such a complex parameter poses substantial challenges.