1. Defining health and wellbeing
The World Health Organisation (WHO) defines health as ‘a state of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity’ (WHO, 1948). This is consistent with the biopsychosocial model of health, which considers physiological, psychological and social factors in health and illness, and interactions between these factors. It differs from the traditional medical model, which defines health as the absence of illness or disease and emphasises the role of clinical diagnosis and intervention. The WHO definition links health explicitly with wellbeing, and conceptualises health as a human right requiring physical and social resources to achieve and maintain. ‘Wellbeing’ refers to a positive rather than neutral state, framing health as a positive aspiration. This definition was adapted by the 1986 Ottawa charter, which describes health as ‘a resource for everyday life, not the object of living’. From this perspective health is a means to living well, which highlights the link between health and participation in society.
A major criticism of this view of health is that it is unrealistic, because it ‘leaves most of us unhealthy most of the time’ (Smith, 2008); few, if any people will have complete physical, mental and social wellbeing all the time, which can make this approach unhelpful and counterproductive (see Godlee, 2011). It fails to take into account not just temporary spells of ill health, but also the growing number of people living with chronic illnesses and disabilities. Furthermore, it might be argued that focusing on ‘complete’ health as a goal contributes to the overmedicalisation of society by pathologising suboptimal health states (see Sections 7 & 8).
2. Mental health and wellbeing
Broadening definitions of health has contributed to improving understanding of the mental dimension of health and wellbeing, and increasing recognition of public mental health as integral to public health. Since the publication of the Government strategy No Health Without Mental Health in 2011, NHS England has been working towards parity of esteem between physical and mental health – in other words, ensuring that mental health is recognised as equally important to physical health in the development, delivery and provision of health and social care services. Public mental health policy aims to improve population mental health and wellbeing, prevent the onset of mental and emotional distress, and increase resilience.
Defining wellbeing is key to discussing and conceptualising mental health and public mental health, with much debate and some controversy over recent years. Wellbeing sits outside the medical model of health as its presence or absence is not a diagnosis. It is widely accepted that subjective wellbeing varies greatly between individuals, as do the factors that contribute to it. This does not mean to say however that it cannot be defined or measured, and there has been considerable progress in this area. This is discussed in the 2016 report Better Mental Health For All published by the Faculty of Public Health and Mental Health Foundation. The report sets out the public health perspective on public mental health, and highlights examples of good practice to improve wellbeing in local populations.
The FPH’s definition of mental wellbeing is synonymous with the WHO’s holistic and positive definition of health, and with the positive psychology approach advocated by Seligman (2000). Positive psychology reflects the core public health principle of protecting and improving health, focusing on keeping people well rather than treating illness. More recently Seligman (2011) introduced the PERMA model of flourishing, which has five core elements of psychological well-being: positive emotions, engagement, relationships, meaning, and accomplishment. Consistent with these definitions is the approach taken by the Wellbeing Institute at the University of Cambridge, which defines wellbeing as ‘positive and sustainable characteristics which enable individuals and organisations to thrive and flourish’. Others nevertheless argue that wellbeing is a social and cultural construct, questioning the value of approaches that attempt to quantify and categorise it.
The relationship between mental and physical health
Mental health and physical health are inextricably linked, with evidence for a strong relationship between the two accumulating over recent decades and challenging the historical notion of mind-body duality. Mechanisms for this association can be physiological, behavioural and social, as identified by the biopsychosocial model of health. The nature of this relationship is two-way, with mental health influencing physical health and vice versa.
Mammalian stress responses (i.e. fight, flight or freeze) are known to affect physiological processes regulated by the autonomic nervous system, including cardiovascular, respiratory, digestive, repair and defence functions (see Porges, 2011). A number of medical conditions have been linked to stress, such as irritable bowel syndrome (Blanchard, 2001), asthma (e.g. Lehrer et al., 2002) and migraine headaches (e.g. Robbins, 1994). Likewise, stronger immune function has been associated with high levels of social support (e.g. Esterling et al., 1996) and hardiness (Dolbier et al., 2001), both of which may modify experiences of stress (e.g. Cottington & House, 1987) and its physiological manifestations (Karlin, Brondolo & Schwartz, 2003). Whilst it is clear that physical ill-health can be accompanied by mental health problems such as anxiety and depression, the resulting psychological state may in turn impede the recovery or stabilisation of medical conditions, thus producing a vicious circle in which wellbeing is difficult to attain (Evans et al. 2000).