This add-on measures the level of cortisol in your blood, a key hormone produced by the adrenal glands in response to stress. Cortisol helps regulate metabolism, blood sugar, inflammation, and the body’s response to physical and emotional stress. Abnormal levels may signal adrenal dysfunction, chronic stress, or conditions such as Cushing’s syndrome or Addison’s disease—even if signs are subtle or not yet noticeable.

Read our complete guide to Cortisol →