Human Biology and Social Inequality
Human Biology and Social Inequality, edited by S.S. Strickland and P.S. Shetty. Society for the Study of Human Biology Symposium 39. Cambridge, England: Cambridge University Press, 1998. 346 pp. $74.95.
A book dealing with the subject of human biology and social inequality is a welcome contribution to the discipline of human biology. As Human Biology and Social Inequality illustrates, social inequality is a major mediator of human health status and ultimately human evolution and is thus not only relevant but of paramount importance. This edited volume, based on a human biology symposium, covers a wide variety of topics and methodological approaches, including analysis of prehistorical, historical, and contemporary data, although most of the papers deal with 20th-century industrialized countries and to a lesser extent with contemporary economically developing and postcommunist nations.
The book is introduced by S.S. Strickland and P.S. Shetty, who pursue an interesting discussion about the classical origins of the separation of biological and social domains of inquiry, presumptions of innate inequality, and more recent dilemmas about “fact” versus “values” in scientific endeavors. They conclude that it is within human nature (at least as far back as Eastern and Western classical traditions) to consider inequality as an intrinsic property; however, they are less explicit about the role of 20th-century academics in challenging this view of human nature. Some more recent history of the disciplines of human biology and epidemiology would have been useful in the introduction, although some of the contributors provide this material in the introductions to their own papers.
The book begins with 2 chapters that provide comparative overviews of the social inequality of health for both short-term and long-term risks among varying social groups in contemporary industrialized countries. Although it is necessary to show the empirical connections between health status and inequality, the chapters that go beyond this to probe deeper theoretical questions are the more interesting contributions.
R.G. Wilkinson, for example, proposes that socially cohesive societies with generally more equitable distribution of income will have overall healthier populations, as measured by life expectancy and mortality data. He argues that we should be more concerned with equality than with the desire to raise living standards. By documenting the links between poverty and reemerging infectious diseases, J.D.H. Porter and J.A. Ogden begin to ask the important question of how we address societal inequality. They point out that epidemiologists and public health researchers in the past have focused on individuals rather than societies at large, and they challenge the reader to reconsider the problem from a broader perspective.
Several of the contributions address not only the evidence of inequality and reduced health status but also the long-term impact of such circumstances. In their chapter on environmental health and social inequality, L.M. Schell and S.A. Czerwinski review studies of high exposure to pollutants among people living in poverty in the United States and other postindustrial nations. Using lead contamination as a case study, they illustrate the deleterious multigenerational effects of high blood lead levels. Lead can pass through the placenta of a pregnant woman to her baby; moreover, poor prenatal and postnatal diet (often the result of low socioeconomic circumstances) can actually increase lead uptake in the child. High blood lead levels may cause cognitive and behavioral defects, thereby continuing the cycle of inequality for the next generation.
Similarly, in her review of childhood undernutrition and educational potential and attainment, S. Stinson points out that studies of malnutrition and intellectual attainment in low-income countries show differences in motor abilities between malnourished and nourished children. Thus it is hypothesized that, because malnourished children have impaired interactions with their environment, their intellectual development is impeded. Stinson also maintains that poor children in many developing countries do not attend school, worsening any intellectual impairments that are already present as a result of malnutrition.
Chronic disease, in particular, non-insulin-dependent diabetes (NIDDM), is reviewed by K. O’Dea. Although a great deal of attention has been paid to hypotheses on the genetic linkages between NIDDM and population groups, O’Dea documents ample evidence supporting a strong connection between lifestyle factors (diet and physical activity) and the occurrence of NIDDM worldwide. O’Dea makes the point that in affluent countries body mass index (BMI) is higher among low socioeconomic status groups, whereas the reverse is the case in poor countries. The rapid change from poverty to affluencethe case for many emerging countries and population subgroups within poorer countries-may in fact be problematic. There is evidence that the combination of excessive thinness at birth and obesity in adulthood may actually be a high risk factor for NIDDM and associated diseases.
E. Voland and A. Chasiotis explore issues of reproductive success with reference to social class in 18th- and l9th-century rural Germany. Using parish record data, they show evidence that land-holding farmers successfully raised to adulthood more children than landless farm laborer families. Although Voland and Chasiotis depict a static class structure, C.G.N. MascieTaylor challenges this perspective with his review of social and geographic mobility among human populations. He argues that adaptation, genetic, and evolutionary studies must include the notion of social dynamism.
The final 2 chapters address policy implications of health inequality in both economically developing and postindustrial countries. C. Stephens reviews urban health and social inequality in developing countries. She argues that in the past much of development work went toward resolving urban-rural differences in poverty, because urban dwellers were seen as a burden on rural dwellers. There is now increasing recognition of dire poverty within cities and indeed a double burden for city dwellers who suffer from both infectious and chronic diseases. The final chapter, written by Y. Ben-Shlomo and M.G. Marmot, emphasizes 1 of the major themes of the book: Health differentials among human populations are primarily due to social causes, including lack of resources and power. They argue that although social inequality will always exist, health and social policies can reduce inequities.
As with any collection of papers based on a symposium, there is a heterogeneity of ideas and material. The contributors’ sometimes opposing views make for interesting reading. The only disadvantage of this format is the lack of cohesive focus and agreement about the major themes of the book. For example, there is a subtheme about Darwinian fitness as measured by reproductive success. Several of the contributors test the hypothesis of differential reproductive success among human groups according to socioeconomic status. The consequences of this hypothesis, however, are not pursued, although there is some implication that poor people are disadvantaged in terms of Darwinian fitness. Surely, however, this should be linked to the 20thcentury situation in which the poor of the world have the highest rate of reproduction, even when infant mortality is taken into account; it is obvious that the advantage of this state is dubious in terms of wealth and population prosperity. An alternative way of viewing human evolution, however, is presented by M.N. Cohen in his chapter on the emergence of health and social inequalities with population growth in the archeological record. A.H. Bittles and Y.-Y. Chew also demonstrate the complexity of the concept of Darwinian reproductive fitness in the human species. They review the history of eugenics programs and show some evidence of how powerful elites are trying to control subgroups’ fertility through state-legislated fertility policies in contemporary East and Southeast Asia.
Despite the variety of topics in this edited volume, the definition of social inequality refers almost solely to socioeconomic status, perhaps reflecting a 20th-century Western bias in which social class and economic status are considered synonymous. Although ethnic inequality is mentioned briefly in several chapters with regard to minority populations in contemporary postindustrial countries, inequalities resulting from indigenous population status and sex are not addressed at all in the book.
In conclusion, Human Biology and Social Inequality will appeal to a wide range of academicians and health policy makers because of its broad coverage of a variety of topics and issues. As S. Macintyre points out in her overview on social inequalities and health, scholarly interest in this topic has been long-standing yet intermittent and it tends to resurface every once in a while. Human biologists in the 1990s have rediscovered these issues and have raised some provocative and interesting findings that will stimulate and inform future directions in human biological research.
McMaster Institute for Environment and Health