Blog — HPA

By Dr. Tracy Tranchitella, ND (ZRT Laboratory) For anyone who has dealt with issues that are related to chronic fatigue has likely evaluated their hypothalamic–pituitary–adrenal (HPA) axis performance through a multi-point salivary test. The hormone Cortisol is measured in saliva when the samples are collected through predetermined intervals throughout a single day reveal one’s physiological resilience and metabolic reserve in response to daily stressors. HPA axis testing is a mainstay in the world of integrative, naturopathic, and functional medicine. For the past 2 years, the world has existed under the constant shadow of COVID-19. To say that we have been “stressed” is an...

Cortisol should increase around %50 in the first 30 minutes on awakening then start to progressively drop the remainder of the day. Three, rather than one, early morning collections are what is needed to accurately assess the CAR; one immediately on waking, one 30 minutes later, and another at 1 hour. Diurnal Rhythm Assessment Thirty minutes after awakening from a good night's sleep, cortisol levels are at the highest they'll be all day. Following the morning peak, cortisol levels then fall to less than half that peak level by noon. They continue to drop to very low levels at night where...