The Physiology Of Stress

Stress is a state of mental tension or worry caused due to a difficult situation. Stress is a natural human response that leads to each one of us responding to the adversity we face in different ways. All of us face stress but to varying degrees, ranging from distress to eustress. The way each one of us responds to stress, essentially determines our mental health as well as physical health.

Stress affects our body in adverse ways both physically and mentally. Following are the different ways in which our physiology is affected by stress:-

1. Hypothalamic - Pituitary - Adrenal (HPA) Axis Activation - Stress induces the activation of the HPA axis, which leads to the release of the Corticotropin Releasing Hormone (CRH) from the hypothalamus, the neuro-endocrine organ of the body. CRH further stimulates the pituitary gland to release Adrenocorticotropic Hormone (ACTH) which causes the Adrenal Gland to ultimately release Cortisol.

2. Cortisol - This is a key stress hormone wh ich increases glucose availability in the body to help manage stress. It also enhances the functioning of the brain and suppresses non-essential functions like digestion and reproduction so that energy in the form of glucose can be available to the body to help cope with stress. Short term increase in cortisol is definitely beneficial to the human body, however, long term increase in cortisol levels may lead to negative health effects like weight gain, diabetes, constipation etc.

3. Autonomic Nervous System (ANS) - Stress activates the sympathetic branch of the autonomic nervous system, which essentially leads to the “fight or flight” response. This response includes increased blood pressure, increased heart rate, increased anxiety and nervousness etc. It also stimulates the Adrenal Medulla to release hormones such as epinephrine and norepinephrine.

4. Immune System - Short term stress boosts the immune system response. Long term stress, however, could potentially lead to suppression of the immune system, making the human body more susceptible to infections, diseases, and disorders.

5. Musculoskeletal System - Stress causes tension in muscles and pain. Pain in the neck, shoulders, and back is extremely common due to stress. Chronic tension could lead to extreme headaches, migraines etc.

6. Cardiovascular System - Chronic stress can cause blood pressure disorders which could eventually lead to atherosclerosis, which is buildup of plaque in arteries. This could result in severe chest pain, also called angina pectoris and heart stroke.

7. Gastrointestinal System - Chronic stress could lead to issues with the digestive systems like indigestion, acid reflux, irritable bowel movement etc.

8. Mental Health - Chronic distress could lead to cognitive impairment, depression, anxiety etc.

Understanding the physiology of stress can help deal with and alleviate stress better. Stress should be taken in a healthy amount and dealt with in a healthy way too.