Evidence check: Cortisol in the context of Haut

Cortisol is a stress hormone measurable in saliva, blood, or hair. In the context of skin, elevated cortisol levels have been associated with acne, eczema, premature skin aging, and impaired wound healing. The evidence comes mainly from observational studies and clinical practice; there are no strong randomized controlled trials proving a direct causal effect. Consumer cortisol tests (e.g., saliva kits) can indicate fluctuations but are often not standardized and can be influenced by time of day, stress, and diet. The concept of 'adrenal fatigue' is not a recognized medical condition. For skin issues, a dermatologist should always be consulted before relying on hormone tests. Safety note: medical supervision is essential for testing minors.