Richard Wilkinson, London, Routledge, 1996, xi + 255 pages, £17.99 (sc).

Why read this book? Read it if you are interested–professionally or otherwise– in the current state of society and the effects this has on our health. And in this case read it even if the complexities of epidemiological research, of anthropology, of social psychology, economics, history or politics are not your home-ground: for though the book draws on all these areas it can and should be read from cover to cover.

Wilkinson's thesis concerns the relationship between relative income and mortality. He shows this relationship to hold very strongly within a given society or social grouping, ie it is the distribution of income rather than its absolute level which seems the more important, particularly so in developed countries. Wilkinson shows early on how relative deprivation becomes a major determinant of health once a society has passed through the so-called “epidemiological transition”–where predominantly infectious causes of death give way to predominantly degenerative causes (cancer, cardiovascular disease, stroke etc), and where the stark relationship between life-expectancy and per capita income declines as absolute incomes rise. (Interestingly, this also seems to mark a change in the social distribution of some major diseases including most importantly coronary heart disease: in affluent societies the so-called “diseases of affluence” actually shift to the poor.)

Wilkinson then looks for possible explanations for those inequalities in health that are associated with living standards. Genetics, and anomalies of classification or measurement, are shown to contribute nothing; the effects of social mobility, medical care and individual health related behaviour provide only a partial influence. This leaves as the major influence the effects of the social and economic circumstances in which people live. “Health . . . gives us a handle of hard data on the subjective impact of experience . . . [We] are discovering the toxicity of social circumstances and patterns of social organisation.”

Wilkinson develops the case for regarding relative income as the more important factor, by re-examining existing data from a new conceptual standpoint, illustrated by neat historical case studies. He considers on the one hand societies experiencing a rapid compression of income distribution, accompanied by dramatic improvements in life-expectancy (as, twice, in wartime Britain); and on the other hand societies experiencing a rapid widening of income differentials, resulting in a breakdown of community cohesion and a sharp increase in deaths from coronary heart disease (as in the small close-knit Italian-American community of Roseto, Pennsylvania in the 1960s). The picture starts to emerge strongly: “inequalities are not an inescapable fact of modern life”.

From here the author develops the concept of social cohesion. He draws on a wealth of anthropological literature, and on ideas from the field of social psychology, to establish the reality of this concept and, more significantly, its crucial role in human health. The huge themes this raises are worth some quotation: “[We] live in ways that are not conducive to social harmony because we are protected [by an overriding authority] from most of the social consequences of doing so . . . only under [that authority's] jurisdiction can the complaints of the dispossessed be safely ignored. “[We] come to believe that human beings are by nature what their culture suggests they are . . . [We] fail to realise how soon a different social order might come to seem a reflection of a different human nature.”

The latter part of the book deals with the possible physical pathways involved. One of the most plausible is the role of chronic stress mediated through the hypothalamic-pituitary-adrenal axis linked to raised corticosteroids, central obesity, insulin resistance, poor lipid profile and increased blood-clotting–with evidence linking all this to the social ordering of the population.

The range and depth of this book do not lend it to compression, since it reads as a whole: it gathers weight and momentum and it strikes up major themes which seem to resonate and coalesce of their own volition, while maintaining an open and balanced feel. The merits of this book lie not only at the level of detailed content (which will inevitably date as research moves on). It can already be seen as a pivotal point in the direction of related research. Its methodology is attractive to the medical humanities, because it runs counter to the fashion for sub-disciplines guarding ever-smaller areas of exclusive expertise, and because it deals with complex issues straddling several disciplines. The value of conceptual thinking is outstandingly demonstrated, as “evidence” takes on new meanings from different viewpoints. Moreover it refocuses attention on the subjective quality of life as crucial for assessments of social vitality, making material and economic aspects of secondary and indirect importance.

Finally the text is accessible, it assumes no specialist knowledge, and it manages to evoke genuine excitement at the “first views of the landscape ahead”. Read on!