What is the relationship between stress and disease?
Medical doctors agree that the psyche plays an important role in the persistence of chronic disease, but because there is no scientific way to study this clinical phenomenon, for a long time it has been ignored. Our disease model is extremely effective when treating acute illness, it saves lives during instances of heart attack, appendicitis and infectious diseases like pneumonia and E. coli. Today, doctors look at the human body as a complicated machine with infinite independent parts. Hospitals are separated into departments with specialties including everything from cardiology to gastroenterology, gynecology, nephrology, endocrinology and countless other areas.
It can be exhausting, stressful, and sometimes wasted effort going from one specialist to the next looking for treatment of vague symptoms that are, unbeknownst to the patient, associated with chronic stress.
Ayurveda looks at the body as a whole. We are a part of one ecosystem, we can not be separated from our external environment let alone separate ourselves from our own inner workings.
The chemistry of life is extremely precise and requires are tightly controlled environment, termed homeostasis. Every function in the human body has a home base that it wants to return to. The bloodstream consists of a mix of hormones, nutrients, and diverse messenger molecules that float through the body and know exactly where they are needed to perpetuate perfect balance.
The body has an internal thermostat that remains at 98.6 degrees F and when you depart from this temperature too far for too long, disease results.
The complexity of maintaining homeostasis requires communication between every living cell in the human body.
We can't look to explain chronic disease with the malfunctioning of a single organ. Instead we must look at how the brain, the gut, and the trillions of other microorganisms living in the body deal with the onset of stress.
The term stress is used in modern medicine to describe on specific disease features including the generalized feeling of being ill, having aches and pains or feeling fatigued. A symptom is subjective, it can be observed by the patient but can't be measured directly. Management of chronic diseases resulting from stress are difficult to treat with pharmaceuticals and surgical procedures that are so frequently used in western procedures.
Many times the elimination of the causative agent does not cure the disease. It's not the microbe, allergen, or harmful ray that cause disease, it is our reaction to these agents that poses the problem.
Think about it. We observe this all the time. Patients remain sick long after the presence of the pathogen has left the body.
The Physiology of Stress
Understanding the biochemical mechanisms that make up the stress response requires an understanding of what happens when a person inappropriately responds to perceived threats. The roles of two peptide hormones, corticotropin-releasing hormone (CRH) and vasopressin play a critical role. Neurons in the hypothalamus release these two hormones into the bloodstream. Vasopressin (also known as the anti-diuretic hormone or ADH) stimulates the cortical collecting ducts of the kidneys to increase uptake of water, decreasing the output of urine during stress. CRH travels through the bloodstream to the adrenal cortex, where corticotropin increases cortisol production.
What is Cortisol?
While cortisol's primary targets are metabolic, it also affects immunity and memory. Cortisol is the primary hormone responsible for the stress response, cortisol's main function is to restore homeostasis following exposure to stress. Stress increases metabolism. Under stress, the body consumes more oxygen and produces more carbon dioxide. When the body detects and increased level of carbon dioxide in the blood, the respiratory center is alerted and breathing is altered. The intercostal muscles work hard to move more air out of the lungs to restore balance in the respiratory system.
When respiration is increased and the adrenal glands sense even more stress.
The hormones secreted by the adrenal cortex are steroid hormones meaning they are not stored in cells. Consequently, their rate of release is dependent on their rate of usage.
The more stress we experience, the more steroid hormones we ultimately have to digest.
Digesting an excessive amount of steroid hormone can be taxing on the body. Which is why we see chronic levels of stress disrupting the delicate feedback balance of the body. Cortisol opposes insulin by encouraging higher blood sugar. Conversely, it stimulates glycogen synthesis in the liver, which decreases net blood sugar levels thereby balancing and regulating the level of glucose circulating through the bloodstream during stress. This is hard work for the body.
With too much cortisol circulating in the body, we observe a weakened immune response and higher instances of repeated colds, allergies, fatigue, and even sugar cravings.
Cortisol blocks T-cells which are lymphocytes produced by the thymus gland that are very active in the immunity.
Studies have also shown that excessive cortisol overwhelms the hippocampus, resulting in memory loss.
Clearly, our bodies are designed to manage a certain level of stress. We have built in mechanisms that allow for the acknowledgment, reaction and digestion of stressful situations. However, too much (of anything) is no good. It's important to identify areas in your life where you can eliminate and manage stress.
Small changes like limiting caffeine (which stimulates cortisol production) and alcohol (which depress nerve cells) consumption can go a long way in optimizing the body's response to stress. Dietary and lifestyle changes prove effective because of the intelligent microbes living in the gut that produce a vast number of genes that help maintain homeostasis even after the most stressful of situations.
Here are some simple, Ayurvedic solutions to overcoming stress and its obstacles.
References: Chopra, D. (1991). Perfect health: The complete mind/body guide. New York: Harmony Books. Lad, V. (2002). Textbook of Ayurveda. Albuquerque, NM: Ayurvedic Press. Marieb, E. N., Hoehn, K., & Hutchinson, M. (2013). Human anatomy & physiology. San Francisco, CA: Pearson Education/Benjamin Cummings. Mayer, E. A. (2016). Mind-gut connection: How the hidden conversation within our bodies impacts our mood, our choices, and our overall health. Randall, M. (2011, February 03). The Physiology of Stress: Cortisol and the Hypothalamic-Pituitary-Adrenal Axis.
Meet the author, Melanie Dolan