What role does Cortisol play in Langlebigkeit?

Cortisol, the primary human glucocorticoid, plays a dual role in longevity. Acutely, it is essential for stress response and energy mobilization. However, chronically elevated levels—due to persistent psychosocial stress, poor sleep, or inflammation—are associated with accelerated biological aging. Research links high cortisol to shortened telomeres, insulin resistance, cardiovascular risk, and cognitive decline. Conversely, longevity studies (e.g., in centenarians) suggest preserved circadian cortisol rhythms and lower basal levels. The evidence is largely epidemiological and mechanistic; long-term randomized trials are lacking. A single cortisol measurement from a home test is of limited value due to strong circadian variation and individual differences. For longevity assessment, repeated diurnal profiles, salivary or hair cortisol, and consideration of cortisol metabolites and binding proteins are more informative. Conclusion: Cortisol is a relevant stress biomarker but not a direct longevity predictor. Interpretation requires clinical context and should not rely solely on home tests.