Stress and Illness – The Mind-Body Connection

For a very long time, people believed that stress can make you sick. But we had no way of scientific proof. With the development and progress of biomedical science, we are now able to prove that there is a definite link between the state of mind and the state of health. The bridge that connects your mind and brain with the body and its overall health is the immune system. A properly functioning immune system protects the body from illness and when the immune system is malfunctioning, we get sick.

This research paper will explore the mind-body relationship and how it affects the immune system and overall health and the life coaching implications.

Immune system

The function of the immune system is to protect our body from infection and disease. The immune system accomplishes this by recognizing “self” from “nonself” cells. These “nonself” cells can be from the outside world (viruses, bacteria, parasites, fungi) or abnormal cells from within our body (cancer). These “nonself” cells are commonly called antigens.

Our immune system is comprised of bone marrow, spleen, tonsils, thymus, lymph nodes, and lymph vessels. All of these organs and tissues are involved in the production, maturation, and activation of our white blood cells. White blood cells, also known as lymphocytes, are “soldiers” that fight infection and disease. There are three main types of white blood cells: T-lymphocytes, B-lymphocytes, and natural killer lymphocytes. There is a constant communication going on between lymphocytes – they chatter about antigens they encountered; stimulate or suppress each other and regulate how our immune system functions. This communication is facilitated by small bio-molecules produced by the cells of the immune system.

T and B-lymphocytes need to be sensitized by an antigen to be able to destroy it. In other words, the immune system must recognize the existence of an antigen, and transmit the detailed information about the antigen to a particular T cell called a “helper” which in turn will stimulate either the production of an antibody or sensitize the T or B lymphocyte directly. Once sensitized, the lymphocytes have “knowledge” about the antigen they are looking for. They know what it looks like and they seek it out and destroy it by engulfing it or bursting it using its biochemical warfare at hand.

Antibodies have a similar function. They also know detailed information about the antigen and create anti-sequences on their surface that will fit only with the sequence of the antigen they are looking for – like your car key that will fit only the lock of your car. Once antibodies bind to the antigen, they either neutralize it using their own biochemical set, or they become beacons for the other lymphocytes, telling them where the enemy is and helping them home in on it and engulf it. Imagine a missile that has received coordinates and is on its way to destroy the target.

Natural killer cells do not need to “know” an antigen to find it and destroy it. They have an innate knowledge, a library so to speak, of what is “self” i.e. normal in our body. Natural killer cells patrol our bodies and analyze the cells they encounter. When they find a cell that does not match their library, they destroy it.

So how do we get sick? We get sick when the immune system is defeated by the challenger. This may happen either due to being challenged by a novel antigen that our body has never encountered before or if the immune system is not functioning properly. In our lifetime we encounter several novel antigens and since our body does not have “knowledge” of its existence, it defeats the immune system. However, this victory is only temporary, and the immune system will identify the novel antigen and mount an immune response against it. A good example would be the flu. Every number of years there is a new flu strain that will cause an epidemic. By receiving a flu shot we give our immune system a jump-start. We inoculate with a small particle of a flu antigen giving our body the knowledge it needs to mount an immune response to this novel flu strain and by doing so protect us against it.

Our immune system gets turned on and off by a complex system and when this system malfunctions and doesn’t turn immunity on or off, it manifests as illness.


Stress is the emotional and physical strain caused by our response to environmental demands. In general, when environmental demands exceed your ability to cope, it creates stress. Stress generally refers to two different things: situations that trigger physical and emotional reactions (stressors) and the reactions themselves (stress response).

The body responds to stress by what is called the General Adaptation Syndrome (GAS). The GAS occurs in three stages – alarm, resistance, and exhaustion. The fight or flight response is the most common type of alarm stage. When our brain perceives something as threatening or challenging it signals an alarm and a series of events occur in the body: increasing heart rate, fast breathing, alertness, muscle response, and increased metabolism rate. These actions get the body physically ready to confront a threat (fight) or escape from it (flight). During resistance, the body’s systems return to normal but remain alert. Following resistance, the body enters exhaustion, at which point it can no longer resist the stressor. The exhaustion state allows the body to recover from stress.

Stress affects the immune system in a very powerful way. There are two types of stress – acute (short-term) and chronic (long-term). Acute stress lasts for several minutes to a week. Acute stress, under most circumstances, boosts immunity. Chronic stress is caused by a long-term stressor that lasts for a year or several years and does not have any clear end point (injury resulting in permanent disability, caring for a spouse with dementia, etc). Chronic stress could also be caused by the cumulative effect of prolonged serial instances of acute stressors. Chronic stress is unhealthy and it has harmful effects on our bodies. Chronic stress can suppress immunity and cause illness.

Negative thoughts and emotions, (anxiety, fear, anger, sadness, pessimism, feeling overwhelmed, etc.) have the same effect on our health as stress so when we talk about stress and its effects we are also referring to those negative feelings as well.

Not everyone reacts the same way to a stressor. Some people have a more profound reaction when exposed to a stressor than others. Those who easily get physically and psychologically stressed are termed “high reactors” and they are significantly more affected by stress than those that are “low reactors”.

Stress, brain, and the immune system – what is the connection?

The pivotal players in communication between the brain and the immune system are hormones and biochemicals produced by the hypothalamus, pituitary gland, and adrenal glands commonly referred to as the hypothalamic-pituitary-adrenocortical axis (HPA axis). The HPA axis coordinates a cascade of events between the brain and the immune system. This communication goes both ways: the brain to the immune system and the immune system to the brain.

When the HPA axis is activated by an alarm sent by the brain several hormones and biochemicals are produced. Most of them are secreted by adrenal glands: glucocorticoids, catecholamines, and peptides. The glucocorticoids and catecholamines are responsible for fight or flight reactions – they prepare our body to survive a threat. And they do the same when we encounter a stressor.

Effects of cortisol

We will concentrate on the effects of cortisol – one of the corticosteroids produced by the adrenals. Cortisol has been known to have immunomodulatory effects. It is given post-surgically to suppress the immune system and prevent rejection of transplanted tissues. However, cortisol at normal levels is essential for the proper functioning of the immune system. An optimal concentration of cortisol is necessary for normal recovery from infection. At normal (optimal) levels of cortisol, our immune system is stimulated – this is how our immune system gets turned on. When immune response is no longer needed, the level of cortisol rises and it shuts off the immune system. On the other hand, if the level of cortisol is low, the immune system keeps on working. So cortisol affects the immune system in three ways, depending on its concentration in the body:

  • Low concentration causes the immune system to keep on running even when not necessary and this can lead to an autoimmune inflammation disease such as rheumatoid arthritis
  • Optimal concentration stimulates the immune system and the immune system functions well
  • High concentration will shut off the immune system, which is good when we get over an illness and the immune system no longer needs to be on high alert, but bad when it happens outside of this scenario.

It has been proven in several studies that stress causes cortisol levels to rise and this is one of the reasons why cortisol was named “the stress hormone”. In acute stress, this rise is short-lived whereas in chronic stress this rise persists causing immune system suppression which increases our disease susceptibility.

Scientific findings

The function of the immune system can be measured by quantitative analysis and so can the level of cortisol. Many studies have been done and they established the correlation between stress, cortisol, and the immune system and its effects on overall health.

Several viruses live in our body but no longer cause any symptoms of the disease. They are called latent or dormant viruses. Studies have shown that individuals experiencing stress are significantly more likely to experience an onset of these dormant viruses – the virus will “wake up” and cause a disease. Several good examples of these dormant viruses are herpes virus (HV), Epstein-Barr virus (EBV), and herpes zoster virus (shingles). Many studies have also found consistently elevated cortisol levels just before or at the beginning of the onset of HV or shingles proving that cortisol at high levels suppresses the immune system and allows for dormant viruses to cause illness.

In one study the levels of EBV were measured in a population with chronic stress (caregivers) and compared to that of a control (normal) population. The EBV levels were significantly elevated in the chronic stress group. This group also had lower amounts of T-lymphocytes and the lymphocytes’ ability to multiply was greatly diminished. [Kiecolt-Glaser JK, Dura JR, Speicher CE, Trask OJ, Glaser R. Spousal caregivers of dementia victims: longitudinal changes in immunity and health.

In another study, the prevalence of acute infectious respiratory illness was compared between the group that was exposed to chronic stress and the group that did not experience stress. It showed that stress was associated with the increased risk of illness and the association was dose-related i.e. the more stress the more chance of illness. [Cohen S, Tyrrell DA, Smith AP. Psychological stress and susceptibility to the common cold. New Engl J Med 1991;325(9):606-656]

In a study done by Frances Cohen et al., the effect of long-term unemployment as a chronic stressor was examined. The unemployed group had significantly lower natural killer cell cytotoxicity (the ability of natural killer cells to neutralize antigens) as compared to the employed group. After some of the participants of the unemployed group gained employment, this new subgroup showed a recovery in their natural killer cell cytotoxicity as compared to their unemployed period. This study successfully documented immune function recovery after the definable end of a chronic stressor. [Frances Cohen, PhD, Margaret E. Kemeny, PhD, Leonard S. Zegans, MD, Paul Johnson, MPhil, Kathleen A. Kearney, PhD and Daniel P. Stites, MD.

Immune Function Declines With Unemployment and Recovers After Stressor Termination. Psychosomatic Medicine 69:225-234 (2007)]

Boost your immune system – get a life coach!

From the studies examined above, it is clear that chronic stress and the prolonged negative predisposition adversely affect our immune system and by doing so we become prone to illness. The removal of the stressor improves the function of our immune system and positively affects our overall health.

Are there ways to put mind over matter? The answer can be found in life coaching. Life coaching is intended to help people manage their lives, get the support they need, align values with goals, and improve their outlook. So, life coaching can significantly lower the level of stress and improve health.

Because life coaching is a partnership between the coach and the client, clients have a stable nurturing, and supportive relationship. This type of relationship is essential in lowering stress in life. Clients become aware that they are no longer alone in their daily trials and tribulations, and this knowledge gives them the strength to move forward in life. A nurturing and supportive life coach is now just a phone call away. What a wonderful safety net!

The life coach also becomes the client’s wise confidante. Dr. Charles Raison MD of Emory University School of Medicine in Atlanta suggests that “People who have one person they can talk to are known to live longer. It doesn’t have to be a healthcare professional. But if you can talk to someone about your emotional baggage, it can help your physical pain too.” What a wonderful application and endorsement of life coaching.

To improve life and minimize stress, it is important to incorporate into one’s life events and people that one enjoys. Life coaches help clients align their own goals with their values. By identifying, incorporating, and prioritizing goals and values connected to events and people that bring happiness, enjoyment, and satisfaction to the client’s life, life coaches help clients achieve better life balance and develop an optimistic, realistic, and hopeful attitude which will improve the immune system function.

According to Robert Emmons, a psychology professor and researcher at the University of California, grateful people – those who perceive gratitude as a permanent trait rather than a temporary state of mind – do much better when it comes to health than not-so-grateful. By utilizing the life coaching technique of reframing we can help clients develop more positive attitudes towards many life events and by doing so improve their overall health. By encouraging clients to keep a gratitude journal or a list of benefits in their lives, we can help clients shift towards gratitude which will in turn improve their immune function and lower incidents of illness. Another tool in life coaching that will help develop gratitude is celebrating. Encouraging clients to always celebrate their milestones, victories and even failures will help them become grateful for good and not-so-good on their life journey.

During the life coaching journey, the coach helps clients develop self-awareness, become self-empowered, and live within the boundaries of their truth which enables clients to become realistic optimists. Researchers at Harvard found that this optimism seasoned by reality can substantially boost the immune system.

In a recent study, two groups of cervical cancer patients were observed – a group that received weekly psychosocial telephone counseling (PTC) as a means of combating stress and a group that did not receive counseling. Quality of life (QOL) and immune function were compared between the two groups. The PTC group yielded significantly improved QOL. Improvements in QOL were significantly and consistently associated with a particular shift in the T helper lymphocyte population resulting in stronger immunity. These findings suggest that PCT has a positive impact on QOL and in the improvement of overall clinical outcomes including survival. Dr. Esther Sternberg, director of the INIM program at the National Institute of Mental Health points out that women in support groups for their breast cancer have a longer life span than women without this type of support. These data strongly suggest that life coaching could be applied to cancer patients to help them overcome stress and negativity and improve their QOL and possibly overall survival.

The evidence is overwhelming that stress and our state of mind greatly influence the immune system and through this connection, overall health. Life coaching techniques and tools help manage life and minimize the effects of stress while at the same time, it empowers clients to assume a realistically optimistic attitude. The coach-client partnership provides a strong support system that is most needed for successful stress management. For mentally healthy individuals who are looking to improve their physical health and well-being, life coaching is a key to success. Life coaching is also affordable, works fast, and is extremely efficient. Boost your immune system – get a life coach!

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