Blog — cortisol profile

  By Dr. Tracy Tranchitella, ND (ZRT Laboratory) The Cortisol Awakening Response (CAR) is the predictable rise in cortisol within the first hour of awakening. There are two events that contribute to this dynamic rise in morning cortisol. The first is in response to adrenocorticotropic hormone output from the pituitary as a part of the normal circadian activities of the hypothalamic–pituitary–adrenal (HPA) axis with involvement from the sympathetic nervous system. The second occurs in response to exposure to daylight with the activation of the suprachiasmatic nucleus in the hypothalamus, which happens within 30-45 minutes after awakening and can increase cortisol...