RELATIONSHIP BETWEEN MIND AND HEALTH
We have often heard stress can cause weight gain, stress can cause acne, stress affects a female’s menstrual cycle and so on. It is established that the mental state and physical health of a person are affected by one another. But in this article we shall dive deeper to understand how that works.
What is health?
The World Health Organization or WHO defines health as “ a state of complete physical, mental, social well being and not merely the absence of disease and infirmity.” WHO (World Health Organisation) states that, not having a disease or illness is not the only criterion to classify one as healthy or unhealthy, one must also be in a state of being physically, mentally and socially fit.
It further defines health as a dynamic state that is it keeps changing and is not always constant for anyone.
Dimensions of health
Health is multidimensional which means it has many components to it. In order to be healthy one must be fit in all dimensions of health. Following are some dimensions of health:
- Physical health – It includes absence of any external injuries, chronic diseases as well as a fit body. Physical health is taken care of by doing regular exercise, taking proper diet and having proper sleep.
- Mental health – It includes having normal functioning cognition, ability to regulate thoughts and absence of mental disorders, excessive negative and distorted thoughts, etc.
- Emotional health – It includes having the ability to understand one’s emotions and feelings and being able to control them rather than being controlled by them. It also means absence of psychological disorders and excessive or prolonged stress, etc.
- Social health – It includes having the ability to make and maintain social relationships and having basic social skills required to function in society, like communication skills, social behaviour, conflict resolution etc.
- Spiritual health – It includes having a sense of meaning and purpose in life and hence motivation to live. It also includes having an identity of own. People lacking identity face existential crisis.
- Vocational health – It includes having a healthy attitude towards work that is having ambitions, motivation to work, career choice and satisfaction and good performance.
Interdependence of dimensions of health
All the dimensions of health are interconnected. This is a very crucial fact. As if one suffers in a particular dimension of health the other dimensions will also be affected. For example a socially unfit person may also suffer emotionally due to lack of meaningful relationships. This will in turn affect their spiritual, physical and mental health which may further affect vocational health as well.
Therefore mental health and physical health are connected, making sense why stress causes so many physical health related issues.
Psychoneuroimmunology
Psychoneuroimmunology is a study dealing with the role of psychological processes and neurological processes in immunity.
Immunity refers to an organism’s capacity to fight against foreign agents (antigens), or germs when they enter the organism’s body and help heal wounds and infections. Immune system of an organism consists of cells, proteins produced by these cells, and organs.
Hence for a healthy, strong body good immunity is essential.
According to psychoneuroimmunology, a person’s mind (emotions, thoughts etc) can influence their immunity.
Understanding nervous system :
CNS or Central Nervous system consists of the brain and spinal cord. It controls everything in our body. It is responsible for maintaining homeostasis (internal balance) in the body by regulating temperature, blood pressure, heart rate etc. To do so the endocrine system and CNS need to communicate. Endocrine system consists of ductless glands that produce hormones (chemicals) and directly release it into the bloodstream.
The body and brain communicate with each other through electrical and chemical signals or messages. The brain sends electrical and chemical signals through neurons. The electrical signals move forward in a neuron and from one neuron to another due to electrical and chemical gradients present between the intracellular region and extracellular region of the neuron. This depolarizes (changes the intracellular region of the neuron’s charge from negative to positive) the region in the neuron (axon). When the electrical signal reaches the end of a neuron, neurotransmitters are released by synaptic knobs of the neuron. These are chemical messengers. They are the ones that carry signals to muscles, glands or other neurons and make communication possible.
Understanding immune system :
The immune system attacks any foreign agent that it doesn’t identify as its own and starts to kill it to avoid any harm to the body. But the immune system sometimes also attacks unharmful agents as well like in case of allergies and also with transplants and sometimes it could be overactive causing autoimmune diseases which are dangerous.
So whenever a foreign agent enters the body and comes in contact with an immune cell, it attaches with its receptors which induce changes in the cell. When the foreign agent attaches to immune cells that are cytokine producing cells, cytokines will be produced. Cytokines are proteins responsible for starting and stopping inflammation and bind with receptors of other cells and help in cell proliferation, direct immune cells to the site of infection, direct immune cells to produce antibodies to kill the pathogen and they also store this memory about the pathogen and how to kill it, so that if it enters the body again shortly, the body can kill it and this time it is quicker to respond.
Understanding connection between immune system, endocrine system and nervous system:
The interaction between the Endocrine, immune, and nervous system is called the immune neuroendocrine network. The brain can control the immune system through the neuroendocrine network or by the autonomic nervous system which produces chemicals which bind to immune cells, similarly the immune system can communicate with the brain by using its chemical messengers (Ader, 2001).
The chemical messengers used by the immune system to communicate with the brain are cytokines – when cytokines reach the brain, they are able to signal the brain that an infection has occurred in the body (Watkins, Maier, Goehler, 1995). Also there is a study showing that Peripheral cytokines reach the brain where they can cause local CNS inflammation and alter neurotransmitter function (Felfer, Lotrich, 2013).
The chemicals used by the brain are hormones and neurotransmitters. The immune cells have hormone(chemical) receptors (chemical receptors) on their cell surface (Stelzer, Arck, 2016). The brain regulates the endocrine system, its chemical secretions and through this, it can regulate the immune system.
Hence the sex of an organism will also affect their immunity. This can be seen in females during menstruation when their immunity changes as their hormones do. Hormones like estrogen and progesterone which are mainly found in females, increase T-helper cells activity while testosterone which is mainly found in males, decreases their activity (Manley et al., 2018). Other hormones like adrenaline and noradrenaline produced by autonomic nervous system also bind with these cells and initiate certain immune responses.
Furthermore a study suggests that the cytokines responsible for inflammation also activate the vagus nerve which can inhibit the cytokines production and ultimately the inflammation (Pavlov, Tracey, 2012), which shows us a pathway used by the nervous system to control the immune system.
How mind affects immunity (psychology and immunology connection) :
Whenever the body is under stress or experiencing mental stress the body releases certain hormones. These hormones have the ability to bind with immune cells and affect one’s immunity. The HPA axis or the hypothalamic pituitary adrenal axis can explain it. The hypothalamus produces corticotropin hormone that stimulates pituitary to secrete adrenocorticotropic hormone. This hormone stimulates adrenal glands to release cortisol. Cortisol is released in response to the stress. The body does it to adjust the body for the situation. The cortisol levels when raised send a feedback to hypothalamus in order to stop any more production of corticotropin hormone and hence cortisol. If there are disruptions in this and there are high levels of cortisol in the body for a long period of time, the body’s immunity is weakened.
There have been many studies on this connection proving that psychological processes especially stress can change immunity, these claim that there will be decrease in NK cell activity, antibody responses, cell-mediated immune responses, and overall generalized reduction in the functioning of the immune system relative to one’s psychological well-being (Gebhardt, Blalock, 1998), and that there is a link between depression, anxiety disorders and inflammation. (Miller et al., 2013). There is also evidence that negative emotions can not only increase or decrease the production of cytokines, hence impacting immune responses in the body but also increase time taken to heal wounds, infections (Glaser, Robles et al., 2002).
References
Ader. 2001. International Encyclopedia of the Social & Behavioral Sciences
Felfer, Lotrich. 2013. Inflammatory cytokines in depression: Neurobiological mechanisms and therapeutic implications
https://www.sciencedirect.com/science/article/abs/pii/S030645221300393X
Gebhardt, Blalock.1998. Encyclopedia of Immunology (Second Edition). https://www.sciencedirect.com/topics/medicine-and-dentistry/psychoneuroimmunology
Glaser, Robles et al., 2002. Psychoneuroimmunology:Psychological Influences on Immune Function and Health
https://psycnet.apa.org/fulltext/2002-01415-007.html
Manley et al., 2018. Crosstalk between the immune, endocrine, and nervous systems in immunotoxicology
https://www.sciencedirect.com/science/article/abs/pii/S2468202017301171
Miller et al. 2013. Cytokine Targets in the Brain: Impact on Neurotransmitters and Neurocircuits
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141874/
Stelzer, Arck. 2016. Immunity and the Endocrine System
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7151910/
Watkins, Maier, Goehler. 1995. Cytokine-to-brain communication: A review & analysis of alternative mechanisms. https://www.sciencedirect.com/science/article/abs/pii/002432059502047M
https://my.clevelandclinic.org/health/body/24585-cytokines
https://my.clevelandclinic.org/health/body/21196-immune-system
https://www.nursingawareness.com/message.php?id=223
https://www.who.int/data/gho/data/major-themes/health-and-well-being
