The relationship between chronic stress and disease and the role of yoga therapy in management of chronic stress
Stress is the term that has been borrowed from physics to measure the internal forces within an object in response to external pressure. This term has been borrowed by an endocrinologist in the 30s to explain the response of the human body to the pressure experienced due to actual or potential changes in the environment. In his book “When the body says no, the cost of hidden stress”, Dr. Gabor Maté (2019, P. 7) defines stress as “a complicated cascade of physical and biochemical responses to powerful emotional stimuli”. This complicated amalgam of physical and biochemical responses emerges when individuals perceive their capacity to cope with the actual or hypothetical demands of the emotional stimuli to be inadequate. During episodes of acute stress, the physical and biochemical responses of the body to the external stimuli helps individuals to respond to the demands of modern life through the fight or flight response, which is essential for human survival in face of perceived danger and threat. When stress becomes chronic, the human body remains in the state of fight or flight for an extended period of time.
The psychoneuroimmunology is a field of medicine that aims to explain the interplay between human mind and body. The field of psychoneuroimmunology studies the unity between emotions and physiology during the stage of development and over the course of life, in health and in sickness (Maté, 2019). This field of medicine reveals that the human psyche (i.e., the human mind and its emotional content) interact with the nervous system to shape the immune defense.
When humans face stress, the body reacts in two stages. During the first stage, the first responder, which is the autonomic nervous system is playing an important rule. The autonomic nervous system regulates the body against stress through the sympathetic and parasympathetic nervous system. The sympathetic nervous system activates the fight or flight response and the parasympathetic nervous system signals when there are no immediate perceived threats, and it is indeed ‘safe’ for the body to relax. The second response of the body to stress is through the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis has a role in regulating body’s response to stress through the release of an amalgam of hormones, which in turn result in release of the body’s main stress hormone, namely Cortisol, from the adrenal glands.
When the stimuli in the external environment induce acute stress, our body releases cortisol to support the fight or flight response. Cortisol has the ability to suppress the immune system and prioritise addressing the immediate danger (or perceived danger) that is threatening the individual’s life. When stress becomes chronic, the release of Cortisol suppresses the production of melatonin, which is responsible for regulation of our sleep and inhibition of tumour growths. The decreases in production of melatonin can put the individual at risk of developing short-term infections and long-term maladies like cancer. Further to this, in the short term, the release of cortisol assures the availability of enough glucose (i.e., energy for fight or flight), nonetheless, over production of cortisol can undermine the body’s healthy metabolism and increase the risk of insulin resistance and Type 2 Diabetes.
Yoga and the Kosha model can help to reduce the impact of stress on the body by regulating the sympathetic nervous system and the HPA Axis. The Kosha model of well-being, which draws on the bio-psychosocial model of well-being can help those who experience chronic stress to evaluate various aspects of their lives, including their physical health, their energy level, their mental state, their intellectual input as well as their sources of joy and bliss. Different yogic practices can help with regulation of these five Koshas. The practice of asanas can support the physical health, increase flexibility, improve digestion, and enhance sleep quality. The practice of breathing exercises can help with energy level. The first two sheaths of well-being, namely Annamaya and Pranamaya are the basis and the foundation for getting access to other koshas, which deal with the subtler aspects of human existence.
