Cortisol

Cortisol, also known as serum cortisol or hydrocortisone, is a steroid hormone produced by the adrenal glands in response to stress and low blood-glucose concentration. It plays a crucial role in various bodily functions, including metabolism regulation, immune response modulation, and blood pressure maintenance. Researchers have found that cortisol levels can be measured in serum, urine, and saliva, each providing different insights into the hormone's dynamics. Clinically, cortisol is a significant biomarker for assessing adrenal function and diagnosing conditions such as Cushing's syndrome and Addison's disease. Elevated cortisol levels are often associated with stress, while low levels may indicate adrenal insufficiency. In the context of athletic performance, biohacking, and longevity, cortisol is relevant due to its impact on energy metabolism and stress response. Athletes and biohackers may monitor cortisol to optimize recovery and performance, while longevity enthusiasts may focus on maintaining balanced cortisol levels to reduce chronic stress-related health risks. However, researchers observed that cortisol levels can be influenced by various factors, including time of day, stress, and certain medications. Cortisol exhibits a diurnal pattern, peaking in the early morning and declining throughout the day. Therefore, timing of sample collection is critical for accurate assessment. Additionally, factors such as acute illness, psychological stress, and physical activity can confound cortisol measurements, necessitating careful interpretation of results.