Stress Physiology and the Impact on Our Health
Author: Gael Wheeler, DO
The presence of the COVID-19 virus has altered our reality globally and so has increased the stress level, personally and collectively. As a physician, I am acutely aware of the downstream health consequences of chronic stress and want to do what I can to minimize the impact. Because knowledge is power, today we are going to delve into how the stress response works and a bit of what we can do to moderate it. Please also see my previous writing for more emphasis on strategies for stress management. (Finding Calm in the Midst of Chaos)
Let’s get started.
Our stress response is ruled by primitive parts of the brain designed to get us out of danger. Acute stress has a defined beginning, middle, and end, where chronic stress is ongoing. How is stress is perceived is how it is responded to. The thalamus region of the brain sends sensory information to the amygdala. The amygdala makes an appraisal of the situation and modulates the response. If you perceive your resources are inadequate to meet a threat, the sympathetic nervous system kicks in with the fight/flight/freeze response. Conscious evaluation is not required for this. This automatic response is designed for very short periods of time. Chronic fear, worry, and rumination feed the stress response. When prolonged, a person can experience physical exhaustion.
Chronic stress can actually alter brain function. Our hippocampus helps us form memories. Chronic cortisol elevation causes the hippocampus to atrophy, resulting in decreased memory, decreased decision-making ability and increased depression. Chronic stress prioritizes quick fixes and usually manifests as either under or overeating. This can result in nutrient deficiencies and excessive weight gain.
Chronic stress can trigger pain syndromes. Chronic muscle tension can alter the physiology of muscles, causing them to atrophy. Physical activity helps decrease the stress response and prevents the cascade of chronic pain syndromes.
Chronic stress can decrease REM sleep. Chronic worry can increase cortisol and disrupt circadian rhythm. Protecting sleep is critical in times of stress. Sleep is when we do most of our restorative functions and is essential for immune health.
With prolonged stress, cortisol is chronically elevated, which suppresses our immune system. When this becomes chronic, the immune system can actually become over-activated leading to autoimmune disease, heart disease, and diabetes.
Using the prefrontal cortex of our brain, we can turn down the emotional response to a situation and re-appraise it. Remembering that ‘this won’t last forever’ and ‘we will have learned a lot’ helps us put our situation in perspective. We can ask ourselves ‘In five or 10 years, how will we feel about this?’.
The insula region of the brain joins the higher and lower centers of the brain and helps us listen to what our body is telling us: pain, hunger, and more. Mindfulness, practicing being present in the moment, helps us tune into the language of the body and the brain. Doing this helps us better choose how to meet our needs. Like a parent whose child is trying to get their attention, we need to stop and listen deeply. An increased awareness of our emotional state gives us more of a sense of control of the problem. Noticing thoughts without judgment and accepting emotions helps us move on.
For more information on the amazing physiology of the stress response, how it can help us, how it can hurt us and what we can do to manage it, there is an excellent book ‘Why Zebras Don’t Get Ulcers’ by Robert Sapolsky.
Keep yourself safe, keep yourself sane and keep yourself happy,
Gael Wheeler, DO