Cortisol, Total, LC/MS

Serum Cortisol measures the level of cortisol, the primary stress hormone produced by the adrenal glands, at a specific time point (usually morning). Cortisol follows a diurnal rhythm (high in AM, low in PM). It plays roles in metabolism, immune response, and stress adaptation. Chronically high levels (due to chronic stress or Cushing's syndrome) or very low levels (Addison's disease, adrenal insufficiency) indicate HPA axis dysfunction and can have widespread negative health effects. Salivary or urine tests (e.g., DUTCH test) are better for assessing the diurnal rhythm.