As we enter the third year of the Covid-19 Pandemic, the fear of it lingers in the background despite the drop of case numbers. Fear has been a frequent or even a constant emotion for so many individuals across the globe. Further provocation of fear has occurred with the stress of war and military conflicts, Wall Street volatility, surging gas prices, inflation rates, strikes, and other potential threats. Many individuals display a brave exterior, but fear and stress take a toll. It profoundly affects your physical health – more than you may realize.
Fear: One of the Most Injurious of Human Experiences
Emotional stress, like fear, provokes marked changes in physiology more so than physical stress of overdoing it or other challenging physical states. As stated by G.W. Crile, MD 100 years ago “Intense emotion, especially fear, is one of the most injurious of human experiences”.
The recent JAMA March 1, 2022 issue revisited some of Dr Crile’s comments in “Exhaustion Produced by Extreme Emotion”. His work showed that in response to fear, brain cells in the cerebellum, cerebrum, brain stem, and spinal cord as well as special nerve fibers in the heart became highly activated. The liver and adrenal glands also demonstrated massive metabolic changes in response to fear.
Studies today support the findings that “emotion causes a more rapid exhaustion than is caused by exertion or by trauma, except extensive mangling of tissue, or by any toxic stimulus except the perforation of viscera.” The result of fear stress negatively affects your entire being.
Global Decline of Emotional Wellbeing
Since the start of Covid-19, emotional wellbeing has declined. Mental health issues with fear, depression, anxiety, PTSD, and stress have sky-rocketed across the globe impacting more than half of the general population. Fear of Covid has actually led to a new disorder named COVID Stress Syndrome. Most everyone can likely agree that fear stress has increased in their lives in recent times from Covid and other concerns.
Fear and the Limbic System
Fear is a natural emotion designed to warn us of a threat to life. Fear and threats trigger powerful responses in the limbic system of your brain especially when you have no control. The limbic system is a group of structures deep within your brain that is involved with control of emotion, motivation, behavior, sense of smell, memory, and the autonomic nervous system.
Fear stress activates the hypothalamus. This structure lies at the center of the limbic system and is a major neurological relay hub for your brain. A significant relay part is the hypothalamus-pituitary-adrenal axis (HPA) where neurochemicals are released from the brain and sent to the adrenal glands when fear or threat occurs. It causes mitochondria in the adrenal glands to increase production of cortisol and other stress hormones that flood your body and engages the fight/flight sympathetic autonomic nervous system. In a crisis, this enables you to run fast or have supernatural strength.
Fear stress also activates the amygdala, another part of the limbic system. The amygdala regulates responses to anxiety, fear, emotional memories, and other processes.
During times of stress and strong emotions, activity levels in the limbic system increase which also ramps up metabolic activity and oxidative stress throughout your body. When acute fear stress is resolved, the fight-flight stress response calms down. Nerve and mitochondrial activity and metabolism down regulate and homeostasis returns.
Chronic Fear Stress Changes Your Physiology
With long-term fear stress, the effects on your body are more pronounced. Your natural homeostasis is disrupted and leads to a multitude of physiological changes. Several hormones become dysregulated and leads to increased heart rate, blood pressure, blood sugar, and insulin levels and results in higher risk for heart disease, stroke, diabetes, and obesity.<