Which hormone is commonly known as the "stress hormone"?

Cortisol is commonly known as the "stress hormone" because it is released by the adrenal glands in response to stress and low blood glucose levels. Its primary role is to help the body manage stress by regulating metabolism, immune responses, and several other critical physiological processes. When a person experiences stress, whether it be physical or emotional, cortisol levels rise to assist the body in coping with the situation.

Elevated cortisol levels can lead to various effects, such as increased energy availability by mobilizing glucose, suppressing non-essential functions (like digestion and reproductive systems), and controlling inflammation. While adrenaline (also referred to as epinephrine) is another hormone released during stress, particularly in the fight-or-flight response, cortisol is more associated with the long-term physiological effects of chronic stress.

Insulin is primarily involved in glucose metabolism and regulation, playing no role in the stress response, while serotonin is a neurotransmitter that helps regulate mood, appetite, and sleep, but is not directly implicated in stress hormone activity. Therefore, cortisol’s association with the physiological processes triggered by stress clearly establishes it as the "stress hormone."