Chronic activation of the hypothalamic-pituitary-adrenal axis suppresses immune regulatory function and increases vulnerability to autoimmune disorders.

Study: Hypothalamic-pituitary-adrenal dysregulation and psychological distress in Crohn’s disease: Insights from acute and chronic stress responses

People with Crohn’s disease, an autoimmune condition, had lower stress hormone levels over time, meaning their body’s stress system wasn’t working right. This suggests that when the body’s stress response is messed up — whether too strong or too weak — it can make autoimmune diseases worse.

Study: Comparative Analysis of HPA-Axis Dysregulation and Dynamic Molecular Mechanisms in Acute Versus Chronic Social Defeat Stress

When stress lasts a long time, the body’s stress system gets stuck in overdrive, which messes up the immune system and makes it more likely to attack the body by accident — like a security guard who starts chasing harmless people.

Study: Chronic Stress and Autoimmunity: The Role of HPA Axis and Cortisol Dysregulation

When you're stressed for a long time, your body keeps releasing stress hormones that confuse your immune system, making it attack your own body instead of germs. This study shows that this is why people under long-term stress are more likely to get autoimmune diseases.

Study: Does stress response axis activation differ between patients with autoimmune disease and healthy people?

The study found that people with autoimmune diseases often don’t have a strong stress response—they may even have a weak one—so the idea that their stress system is overactive and causing their disease doesn’t match the data.