Implementing Systems Prevention requires a re-examination of the meaning of ‘health’. A positive definition is needed to replace the negative definition (absence of disease) that is common currency. Political philosophy provides this positive definition. Lawrence Hamilton is concerned with the role of values versus the role of needs in democratic discourse. He recognises that human needs change and he describes some basic categories of these needs. He equates ‘health’ with satisfaction of these needs. In this chapter, these needs are discussed using insights from biology and ‘health’ is redefined as the optimal satisfaction of these needs. The needs are contrasted with definitions of health by the World Health Organisation.
This chapter demonstrates how people perceive risk through a lens of hopes and fears. Perceptions of risk are illustrated by how we react every day to predictions of changes in the weather. When precise estimates of risk are hard to make, institutions manage risks to and within their organisations by using risk matrices based on experience of how severe are the effects of a risk being realised. This may take the form of a traffic light system that combines the scale and severity of a risk. In a health context where there is sufficient data such as the health risks of tobacco use, risk can be measured more precisely allowing the ascertainment of relative risk, absolute risk and attributable risk.
The case is made that the high prevalence of common long-term conditions justifies describing them as modern plagues. The symptoms of the principal conditions are described. These conditions are considered in the context of their impact on curtailing healthspan - the age at which people come to the end of their fully healthy lives. While medical healthcare has extended lifespan, the curtailment of healthspan results in years or decades of disability. This gap between healthspan and lifespan diminishes as deprivation declines.
This chapter reframes Darwin’s ‘natural selection’ as ‘natural prevention’. Much of what Darwin described as natural selection can also be seen as the action of biological systems (organisms in their environment) in the prevention of disease and death whether through lack of optimal nutrition or through predation. The chapter looks at how conscious action for such prevention of disease and death, what the authors call ‘Systems Prevention’, is enabled in a species with the advanced communication skills that underpin human consciousness. This unique human capability creates for humans a conscious choice: do they wait for the action of natural prevention against a disease or do they elect to attempt systems prevention? Use or recognition of this human capability is illustrated in pre-history and in ancient civilisations.