With the prevalence of chronic stress affecting individuals worldwide, the subject of stress and its relation to illness has fuelled an abundance of research. The main essence of chronic stress is the body’s psychological and physiological response to coping with and adjusting to real or perceived threats which are excessive or unrelenting. Such stressors can be defined as emotional, physical, social and environmental demands brought on by fear, intensive exercise, illness, negative relationships or poor living conditions (UMMC, 2011). This essay sets out to discuss the physiological consequences of chronic stress on the body, with particular attention to the impact that it has on the Nervous, Endocrine, Cardiovascular and Immune systems.
The human body is naturally equipped with a built in mechanism which provides a biochemical reaction that adapts and responds to stress, and this is referred to as the ‘Fight or Flight Response’ (Harari & Legge, 2001: 75). The two main controllers of the stress response are the Sympathetic Nervous System (SNS) and the Hypothalamic-Pituitary-Adrenal (HPA) Axis. In responding to biochemical and environmental demands, both these systems work together in tandem via a feedback loop and are responsible for ensuring timely control and activation of physiological responses and maintenance of homeostasis throughout the body (Tortora & Derrickson, 2012: 713-714).
The first stage of the stress response (Tortora & Derrickson, 2012: 715) occurs when the hypothalamus in the brain detects stress and switches on the Sympathetic Nervous System (SNS) to induce a rush of adrenaline. The SNS activates body functions involved in the stress response by releasing Noradrenaline via the sympathetic nerves and Adrenaline and Noradrenaline via the Adrenal Medulla. These neurotransmitters work to increase heart rate, blood pressure, cellular metabolism and bronchial dilation with a view to ensuring that adequate oxygen, nutrients and...