Lesson 6: Medicine, Science, and Health

There is a need to understand the history behind framing health as individual choices or behaviours to better appreciate why an ecological health approach looks like and its significance in eradicating health inequities.

Early Christianity saw disease and illness as divine punishment, believing it could only be alleviated through repentance and prayer. This belief discouraged the use of Nature, such as medicinal plants for healing (source). This belief set part of the course of individualising disease and disconnecting disease (and healing) from the places we inhabit. 

Moving along to the age of the science method, rooted in Greek and Cartesian philosophy of mind and body dualism. Health was severed from its metaphysical and spiritual aspects and instead, focus was placed on bodily biological factors. This came to be known as the ‘biomedical model of health’, which emphasised a ‘bottom-up’ reductionist and mechanistic view of health, where health was seen merely as the absence of disease (Tamm, 1993) (Rocca & Ajum, 2020).

The reductionist approach of the biomedical model of health, whilst having utility in the medical domain, provided a scientific basis for discourse of so-called ‘degeneracy’, the idea that differences in health and societal outcomes across a population could be solely attributed and explained by biologically-based inheritable mechanisms. This spurred obscene solutions of racial and societal cleansing, made popular for example by the Eugenics movement in Britain and the Nazi regime (Nye, 1993).

Today, parts of this framing are still evident, we only have to look at how racialised Black communities were seen as inherently being more vulnerable to Covid-19 due to genetics rather than the consequences of their racialisation (source).

The biomedical model of health failed to adequately account for wider causal psychological, and environmental factors and so there were calls to expand upon the biomedical model of health by acknowledging ‘top-down’ factors that also contribute to health and disease.

This has come to be known as the biopsychosocial model of health, which emphasises an interplay between biological, psychological and socio-cultural factors in determining health and disease. Biological factors themselves are seen as necessary but not sufficient cause of disease, and so ‘top-down’ psychological, behavioural and socio-cultural factors must be be taken into account, where an individual's health is a psychophysical phenomenon that is socially situated (Engel, 1977; Tretter & Löffler-Stastka, 2019).

This conception of health aligns with the WHO’s definition where “health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” (World Health Organisation, 2020). 

The biopsychosocial model of health was built upon by new ecological models of health, that emphasised the complex relationships between wider ecological factors (e.g. biodiversity, pollutant exposure, socio-economic issues) and the individuals lived experience in contributing to health and disease. Ecological models of health, similar to Indigenous models, situates health as a balanced interplay between Nature and individual with emphasis on human health acting reciprocally with planetary health (source 1, source 2, source 3).

This model of health aligns with Indigenous concepts of health, such as of the Aboriginal and Torres Strait-Islanders, which conceptualise health as not only an individual-level phenomenon but one that extends to the wider community. With this view, a person's health and wellbeing is deeply connected to the community's physical land, and social, emotional, and cultural functioning across the lifetime (source). Dr. Camacho, a Quechua midwife, medical doctor, and scholar says that healing is in the soil, we heal the soil, we heal the people (source). Centric Lab takes a similar ecological approach to health that acknowledges the dynamic interplay between external antecedents and internal biological systems - defined as “the ability for our biological systems to enter stability after experiencing trauma or stress throughout our entire lifetime, to give us all an equal opportunity to realise our full potential.” (Centric Lab, n.d.).

Taking an ecological approach to health necessitates the idea that the state of health is the result of a constant negotiation between the human and their environment. It positions that we can only be healthy when the systems around us are healthy, these include the natural environment as well as the social, built, and economic environments.

One way this negotiation is embodied is through a process known as ‘allostasis’ (AL) - which refers to a process of “achieving stability through change” (source) to adapt to environmental demands and maintain biological equilibrium. Allostasis encompasses many physiological, cognitive and behavioural regulatory processes in animals and plants (source).

Allostasis is part of the human stress-response which involves regulatory systems such as the neuroendocrine (hypothalamic-pituitary-axis / HPA-Axis), autonomic (sympathetic nervous), metabolic and immune systems. If an individual is constantly exposed to new environmental demands, unable to adapt to a stressor, or adequately respond, they will experience wear and tear of these systems through what is known as ‘allostatic load’. If this continues, allostatic load eventually results in ‘allostatic overload’ manifesting as disease and death (source, source2).

Although our bodies are designed to adapt to and regulate threats, these must be within the parameters of natural origin and natural biological time. For example, we are able to adapt to thermal changes in real-time if the increase is gradual and in time with our biological systems, if not we can suffer heat stroke. Or in the context of evolutionary time, the Inuit, for example, have adapted to extreme cold through generational genetic changes (source). However, genetics is not the only way that we learn to adapt, we also use cognition, in the case of the Inuit, they have also adapted through creating habitat specific housing, clothing, diet, technologies, tools, and culture (source).

In contrast, we are now living in an era where environmental demands are increasingly rising in both concentration and composition and can be attributed predominantly to anthropological industrial causes. Demands such as air pollution have increased globally in both concentration and diversity of particulates that go beyond our biological capacity, preventing effective adaptation by both plants and animals (source1). Similar trajectories have been shown for global temperatures which are doubling in rates since the 1980’s (source), global light pollution has increased between 270 to 400% (source), and noise pollution, which has been shown in a recent report by the European Environment Agency to affect 20% of EU citizens, who are exposed to noise levels that are harmful to health. This number is expected to increase as urbanisation and mobility demands rise (EEA, 2020).

When these ubiquitous changes in the environment are paired with psychological stressors such as the experience of poverty our biological systems can become dysregulated through a process called allostatic overload (source). There is now substantial research that links allostatic overload to various diseases such diabetes, depression, PTSD, and obesity (source).

In psychology, trauma can be defined as the reaction to a deeply distressing or disturbing experience. In medicine, trauma is defined as a physical injury.

Common examples of trauma experiences include physical and sexual abuse, verbal or emotional abuse, childhood neglect, intimate partner violence, accidents or disasters, illness, incarceration etc. Further, there are several ways in which these traumatic events are experienced (source, source). These include the direct experience of single (acute trauma) or multiple (repetitive trauma) traumatic events either as an adult or as a child (developmental trauma). Further, trauma can be experienced through close individuals (vicarious), particular groups or populations (historical trauma, collective trauma) as well as generations (intergenerational trauma). 

Trauma also creates systemic biological and cellular changes. For example, it can change our gut bacteria environment, which has implications for obesity (source). In cases of acute trauma, some can experience PTSD, which creates neurobiological abnormalities which alters the function of various biological systems, this too has implications for obesity (source). 

Trauma and Hyper-vigilance

The cumulative experience of discrimination can lead to a life that is filled with trauma, and it can also lead to specific acute experiences of violence, which is a form of trauma (source). One of the consequences of trauma is the feeling that we need to be in constant alert in our socialisations and physical environments. Most of our trauma is rooted in the social dynamics dictated by supremacy structures. Whether it is gender-based violence, such as femicide, or the constant emotional and physical abuse of Trans and racialised Peoples (source) (source) (source).

Hyper-vigilance can also lead to specific poor health pathways. Hyper-vigilance, or a heightened awareness and anticipation of protecting oneself against additional trauma, is a key feature of post-traumatic stress disorders (source) and is one of the proposed pathways through which trauma leads to poor cardiovascular and metabolic health, substance abuse (source), and sleep disturbances (source). Anticipatory stress and vigilance, or the impact of anticipating a discriminatory experience, are also examined in discrimination research. In a review of racial discrimination, vigilance was also positively associated with sleep disturbances, high blood pressure, waist circumference, and depression (source).

Systemic Trauma & Structural Violence

Norwegian sociologist, Johan Gultang, introduced the term structural violence in the 1960s to describe the outputs of racism, classism, sexism, and other marginalisations (source). He defined structural violence as an “avoidable impairment of fundamental human needs” (source).

In this we can see that the city and urban experience can be a force of structural violence. Due to conscious decisions, structural forces such as laws, policies, regulations, and practices can coalesce to create a trauma on biological systems.

The last factor about community health to consider, and the ethical use of evidence in policy is, in the words of the World Health Organisation, to consider the impact on the whole population. In order to do this it’s important to ensure that methods that involve population data and analysis have a scientific basis in order to prevent inequities from being entrenched in policy.

When considering the impact on the whole population it’s important to not look at this through the lens of ‘averages’ but of vulnerabilities within. As discussed in a previous lesson, the wear and tear on people’s regulatory systems can make them more vulnerable or susceptible to changes in their environment. Meaning that their risk of impact can be higher than what an average value might present.

Our definition of susceptibility is: the effects of biological inequity on the human immune response, specifically the fact that persistent environmental stressors on a community place these individuals at a heightened risk of developing severe symptoms and chronic illnesses compared to a normative population, not exposed to significant stressors.

An example epidemiological study on this was conducted by Saez and Lopez-Casasnovas (2019) who presented a comparative study on susceptibility between a deprived vs wealthy neighbourhood in Barcelona to pollution. The results indicated that the deprived neighbourhood was significantly more at risk of dying (30% higher probability) from environmental health hazards, such as air and noise pollution, than the wealthy neighbourhood.

This increased susceptibility was due to a mixture of psychosocial stressors that the deprived neighbourhood was experiencing: low income and poverty, low quality of housing and low access to services. Another study (Rosa et al., 2019) showed compelling evidence of a relationship between prenatal stress and onset of asthma in children. Children born to mothers who experienced high psychosocial stress (eg. divorce, health concerns etc), were significantly more at risk of developing asthma later on in life; the risk further increased when the mothers were also exposed to higher air pollution levels (Rosa et al., 2019).

Expanding on this, Landeo-Gutierrez et al. (2019) argue that certain types of psychosocial stressors, such as exposure to violence and crime, increased the risk of onset of asthma, especially when in co-presence with air pollution. In particular, they found a strong correlation between post-traumatic stress disorder (PTSD) and asthma onset.