Circadian Rhythm Disruption in Aging: Mechanisms, Health Consequences, and Restoration
Circadian clocks govern virtually every physiological process — metabolism, immune function, DNA repair, and hormone secretion follow 24-hour rhythms entrained by light. With aging, the circadian system weakens: clock gene amplitude declines, light sensitivity decreases, and circadian outputs desynchronize. Strengthening circadian inputs through light exposure, meal timing, and physical activity has evidence-based effects on sleep, metabolic health, and biological aging.