Which hormone is mainly responsible for the body's stress response?

The hormone primarily responsible for the body's stress response is cortisol. Cortisol is a steroid hormone produced by the adrenal glands and plays a crucial role in the body's physiological response to stress. When confronted with a stressor, such as a threat or emergency, the body triggers the hypothalamic-pituitary-adrenal (HPA) axis, leading to increased secretion of cortisol.

Cortisol helps mobilize energy resources by increasing glucose availability in the bloodstream, suppressing non-essential functions such as digestion and immune response, and facilitating various adaptations to stress. This allows the body to manage immediate challenges effectively, making it essential for survival during stressful situations.

While adrenaline (also known as epinephrine) is released during stressful situations and contributes to the "fight or flight" response, cortisol has a more prolonged effect, sustaining the body's response to stress over a longer period. This is why cortisol is often referred to as the primary stress hormone. Each of the other hormones mentioned plays distinct roles in the body, but cortisol is pivotal in the stress response mechanism.