Abstract. This paper explores the physiological and pathophysiological responses of the human body to stress. Stress, defined as any challenge that disrupts homeostasis, triggers complex mechanisms involving the nervous, endocrine, and immune systems. Acute stress activates adaptive responses, such as the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system, which prepare the body to handle immediate threats. However, chronic stress leads to sustained hormonal imbalances, immune suppression, and increased inflammation, contributing to various diseases including cardiovascular disorders, diabetes, and mental health issues. The dual nature of stress highlights the importance of effective management strategies to maintain health and prevent disease progression. This paper also discusses current understanding of stress-immune system interactions and suggests holistic approaches for stress reduction and health improvement.