No one is immune from stress. According to Merriam-Webster, stress is defined as “a state of mental tension and worry caused by problems in your life, work, etc”. Despite its negative connotation in popular culture, this mental state can be both beneficial and harmful.
An example of ‘good stress’ would be the short, intense burst of tension or anxiety that is felt before events like a test or job interview. Good stress is beneficial because it can provide a temporary extra boost of energy or alertness, which increases performance. Good stress also manifests in the fight or flight response. This chemical reaction occurs when a threat to survival is perceived, and triggers a physiological reaction. An example of the fight or flight response is when we get startled by a loud noise. We have developed this response as a means of survival.
When stress is prolonged or unrelenting, it becomes known as chronic stress. Chronic, or bad, stress can be detrimental to mental and physical health. Constant worry about things like family or work problems are examples of chronic stress. Post-traumatic Stress Disorder (PTSD) is another form of chronic stress. This condition occurs when someone is directly involved in or witness to a traumatic event like combat, an accident or natural disaster. In individuals with PTSD, the fight or flight response basically stays on rather than shutting off once the threat has passed.
How stress weakens the immune system
When long term stress becomes chronic, many systems in the body are affected. Chronic stress results in high levels of cortisol and other corticosteroids circulating in the blood for a long period of time. While there are few side effects from short term exposure to these hormones, over the long term mental and physical damage may occur. People who suffer from chronic or long term stress can experience symptoms like anxiety, depression and sleep problems. Physically, they risk high blood pressure, heart disease and digestive problems. Another danger they face is a weak immune system.
The immune system is the body’s form of defense. It is comprised of organs, tissues, cells and cell products that all work together to fight harmful substances like the pathogens that cause infection and disease. There are two main ways that stress has a direct, negative effect on the immune system:
1. It creates chronic inflammatory conditions
2. It lowers the immunity of those who otherwise might have a healthy immune system.
According to Dr. Mary Meagher, “people exposed to chronic social conflict experience high levels of stress and consequent dysregulation of the immune system, thereby increasing vulnerability to infectious and autoimmune disease”.
Cortisol suppresses inflammation during a response to stress. If it is present in the blood for long periods, the body develops a resistance to cortisol and does not respond to it properly. Instead, it ramps up production of substances that actually promote inflammation leading to a state of chronic inflammation. These pro-inflammation substances, called cytokines, are associated with a host of chronic inflammatory and autoimmune conditions. Autoimmune conditions occur when the body basically mistakes itself as a threat and attacks itself. Examples are fibromyalgia, rheumatoid arthritis and lupus. Other chronic conditions include diabetes, heart disease and cancer.
Chronic stress also results lower amounts of a protein that is critical to signaling other immune cells. Without these reinforcements, the body is susceptible to contacting acute illnesses, and prolonged healing times. Lymphocytes are a major component of the immune system. They kill invading organisms that would cause disease and they recognize harmful substances and help defend against them. Cortisol and corticosteroids suppress lymphocytes. With a lowered amount of lymphocytes, the body is at increased risk of infection and disease.