The psychology of the immune system

psychology of the immune system holistic retreats

We all need a healthy immune system to help regulate and protect us. In this article we look holistically at the important role of psychology in maintaining a healthy immune system. The good news is that when we look at the immune system from a holistic standpoint and introduce psychology, we can make balanced lifestyle choices that can lead to long term immune system health and wellbeing.

An introduction to the immune system

There are, broadly speaking, two components to our immune system: 

  • The innate immune response, which is fast acting and defends us from general threats. This response includes inflammation processes and non-specific white blood/immune cells.
  • The specific immune response, which is slower and targets specific threats (for example specific viruses) via specialised immune cells.

This article focuses on the innate immune response and explores the link with our psychology.  Many of the principles discussed in this article can also be applied to the adaptive immune response.

The innate immune response is associated with primitive symptoms in the body such as inflammation, a fever and swelling.  These changes are associated with activating and enabling specific white blood cells, which can be seen under a microscope “fighting off” infection.

How psychology affects body chemistry

Our perceptions of an event (or future event) help determine whether the body can relax or whether the body needs to prepare itself for an imminent threat. There are “pathways” (chemical processes) that are dependent on our psychology to identify imminent threats and bring us back into balance.

When we are feeling supported and/or relaxed we trigger activation of the parasympathetic nervous system in the body.  Blood is moved away from body extremities and into the digestive and rebuilding/renewal systems of the body.  The body chemistry is dominated by hormones such as serotonin, dopamine, oxytocin, and oestrogen.   The parasympathetic nervous system can be activated through various relaxation techniques, including meditation and yoga.

When the opposite happens and we are feeling challenged or stressed, we trigger activation of the sympathetic nervous system in the body.  Blood is moved away from the digestive system and towards the extremities (especially the muscles and systems associated with “fight or flight”) and the body chemistry is instead dominated by testosterone, cortisol and histamine.

Of course, in a healthy individual we have both systems operating efficiently and they typically work together for homeostasis (homeostasis is described in more detail below). In other words, for a healthy individual, in the long term, one system would not dominate over the over.

Activation of the sympathetic nervous system is directly associated with the inflammatory response of the immune system (technically this is linked to the relative dominance of testosterone and histamine).  Interestingly the other “fight or flight” hormone cortisol normally acts to dampen down the inflammatory response (see more on the important role of cortisol this later in this article). 

The body’s natural re-balancing systems

What we focus on and how we feel are linked with our body chemistry. If we look at the links between psychology and body chemistry, there are two categories of “pathway”:

The first pathway is a positive feedback system, which, in simple terms, describes the situation when something perpetuates itself.  An example of a positive feedback system is tasting something nice and wanting more of it.

The second pathway is a negative feedback system, which describes the situation when something has the effect of reducing itself.  The hormones associated with feeling full (so not wanting any more food) is an example of a negative feedback system for our food intake.

The body needs both systems to help ensure our body chemistry and psychology can remain balanced (or in homeostasis).  Efficient negative feedback systems become particularly important when body chemistry changes are triggered from an external threat. (Physical traumas can dramatically change our body’s physiology and we need the body to be able to heal as soon as possible). 

Cortisol and the immune system

As we have already said, when our body or psychology perceives a threat, our sympathetic nervous system is activated.  We only need to deal with a threat whilst it is there of course, so for homeostasis, we need a negative feedback system in the body to help us re-balance when the threat has gone. 

One of the key hormones involved in the negative feedback cycle is cortisol. Cortisol dampens down the effect of the immune response associated with perceived threats.

However, science now confirms that prolonged or excessive cortisol secretion can also indirectly cause inflammation.  This means that the ability of cortisol to dampen down the body’s stress responses diminish with time. 

In other words, excess cortisol is one of the key pathways by which chronic (long term) stress can damage the normal functioning of the immune system. 

The impact of long term (chronic) stress

Stressful situations in our lives come and go and are a normal part of life. Our “stress” levels naturally go up during the day and go down at night when we sleep. If our body’s feedback systems are working normally, we experience wellness and can let things go.

However, our psychology can exaggerate or distort threats that can result in chronic anxiety.  We can also live our lives trying to avoid stress, which is unrealistic.  Chronic states of anxiety can impact our body’s physiology and our immune system.   If we are stuck in chronic states of stress the body may need assistance in bringing your body chemistry back into balance to be able to let it go.  Assistance can come through activities which active the parasympathetic nervous system (like yoga and meditation).

Chronic inflammation

We have already mentioned that the immune response can be characterised by inflammation.  The full purpose or benefits of inflammation in the body are still not agreed in the scientific community.  However, there are short-term benefits to inflammation in the body helping it to fighting infection or tissue damage.  For example, inflammation makes it easier for immune system cells to pass through blood vessels to help areas of the body affected.

If inflammation, however, continues in the long term (chronic inflammation) it can begin to damage tissues in the body including arteries and joints.  Left unchecked scientist agree it can lead to serious conditions including heart disease, obesity and cancer.

Excess “rest and digest”

This article would not be complete without considering the psychology and impact on your immune system of consistently minimising or avoiding stress in your life!

In the same way as for the sympathetic (“fight or flight”) nervous system, there are negative feedback systems for the parasympathetic (“rest and digest”) nervous system that aim to ensure long-term homeostasis.  One example already mentioned is the full feeling we get after mealtimes. However, in the same way as for the sympathetic nervous system, it is possible for this negative feedback system to be distorted (for example, through chemical imbalances caused by chronic stress).

Eating food activates the parasympathetic nervous system, as does rest and relaxation. A dominance of “rest and digest” means we are likely to overeat and avoid exercise.  This can easily lead to obesity.

Scientific studies have consistently shown that obesity is associated with a lower functioning immune system and higher rates of illness.  The mechanisms are not always clear but white blood cell counts and the communication between immune cells become impaired.

Conclusion: maximise your health and wellbeing

I have always been a great believer in the age-old philosophy everything in moderation to maximise your health and wellbeing.

If we are looking to improve the functioning of our immune system, it can not only help to listen carefully to any symptoms we have in the body but also to watch our psychology. The body will first give us mild symptoms when our body’s systems are out of balance.  Psychologically, we may mentally have difficulty letting day to day issues go.  If we do not find a healthy way to help activate the negative feedback systems in the body, this article demonstrates how our symptoms can extend to chronic anxiety, obesity and illness.

Some of our guests who come to the retreat feel tired and want to relax and rejuvenate.  Others come to lose weight and do as many exercise classes as they can.  Most of our guests are somewhere between.  No matter your starting point, the La Crisalida Retreats programme will help you to re-connect, re-balance and re-energise and as a result boost your immune health.

About the author

John is one of the founders of La Crisalida Retreats. He is a life and success coach, Transformational Coach and a master trainer in NLP. He leads our life makeover programme as well as overseeing the retreats.