Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — HPA axis

Stress, Cortisol, and the Hormonal Loop of Anxiety When the body perceives danger, the brain activates the hypothalamus-pituitary-adrenal (HPA) axis — an internal alarm that releases cortisol, the body’s primary stress hormone. For short-term challenges, cortisol is beneficial. It sharpens focus, boosts energy, and prepares muscles for quick action — the classic “fight or flight” response that once ensured survival. When Stress Becomes Chronic Trouble begins when stress never switches off. Prolonged cortisol exposure interferes with healthy brain function, damaging neurons in the hippocampus (responsible for memory) and the prefrontal cortex (which governs decision-making and emotional control). As these areas...

Stress isn't always the enemy of memory. Discover how cortisol and stress hormones shape the brain's ability to learn, and what you can do to keep your stress response in balance.

Discover how saliva and blood cortisol testing reveal adrenal function and help diagnose stress-related hormone imbalances like fatigue, anxiety, and burnout.

  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...

Your body's stress response is controlled by three key chemical mediators: norepinephrine, epinephrine, and cortisol. When these become dysregulated — through chronic stress, allostatic overload, or HPA axis dysfunction — the consequences extend far beyond fatigue. This article explains how the stress response works, what happens when it can't self-regulate, and how hormone and neurotransmitter testing can reveal the specific imbalances driving your symptoms.