How are Cortisol and skin aging related?

Cortisol, the primary stress hormone, can accelerate skin aging through multiple mechanisms. Chronically elevated cortisol levels promote collagen and elastin breakdown, leading to wrinkles and loss of firmness. Cortisol also impairs skin barrier repair and increases inflammation, which generates oxidative stress. Observational studies link chronic psychological stress to premature skin aging, e.g., higher cortisol associated with more facial wrinkles. However, the evidence is mostly mechanistic and observational; robust clinical trials directly measuring cortisol and skin aging are limited. Consumer cortisol tests (saliva, hair) are not validated for skin aging prediction. Lifestyle interventions like stress reduction, adequate sleep, and a diet rich in antioxidants may mitigate cortisol's effects. Caveat: cortisol fluctuates diurnally and is influenced by many factors; a single test is not diagnostic. Evidence: human-moderate.