07 September 2011

Floud, Fogel et. al. on "Technophysio Evolution"

I recently reviewed "The Changing Body: Health, Nutrition, and Human Development in the Western World Since 1700" by Roderick Floud, Robert Fogel, Bernard Harris, and Sok Chul Hong for the journal Science.

The book offers an authoritative summary of the field of "technophysio evolution" (in short, how work and technology interact to express themselves over the generations via the size, composition and functioning of the human body). In doing so, they generate new insights into contemporary development processes. My main critique of the book is that the authors understate our ability to do something about the trends that affect our bodies.

Here is the my review

Book Review: The Changing Body. Health, Nutrition and Human Development in the Western World since 1700. Authors: R. Floud, R. Fogel, B. Harris and S.C. Hong. 2011.

This book uses the “plasticity, flexibility and responsiveness” of the human body to changes in nutrition, disease, work and warmth to generate long term insights on human development. The opening chapter is centred on a series of assertions which set up the book’s narrative: (1) the nutrition status of a generation determines its longevity and ability to work. Individuals with a better nutrition status (manifest as height for age and weight for height and the result of the net accumulation of energy and nutrient intake, infection, care and activity) have better brain development, stronger immune systems, and are less likely to succumb to certain chronic diseases later in life, (2) the work of that generation, when allied to technology (broadly defined) determines the generation’s output, (3) the output of a generation is partly determined by its inheritance from past generations (i.e. malnourished mothers are more likely to give birth to malnourished babies) and determines its standard of living through the enhanced ability to acquire material goods and the exertion of agency, (4) the standard of living of a generation determines the nutrition status of the next generation (through the ability of adolescent girls, pregnant women and parents to get access to food, health services and care for themselves and their children), (5) and so on.

This circle underpins the central theory of the book: “technophysio evolution”, a link between technological and physiological change. The authors explain that this kind of evolution differs from conventional forms in its emphasis on the control that humans have over their environment and its rapidity. The next two chapters review the evidence behind these assertions (using equations and lots of data), and the three chapters prior to the summary concluding chapter examine, in great detail (again with many data points provided), these “technophysio evolutions” in England and Wales, continental Europe and the US. Adult heights and life expectancy in these three regions have responded very rapidly to improvements in diet, disease prevention and sanitation over the past 300 years. Today, for example, adult males in the UK are, on average, 10 cm taller than their counterparts in the early 18th century and their life expectancies at birth have doubled.

My own work centres on the links between income, food consumption and nutrition, the links between nutrition and productivity and the distribution of food and other resources within households in a developing country context, so much of this territory is familiar. Nevertheless, the book makes several important contributions. First, because a number of the authors are historians the book introduces a “long view” into the relationships between different variables. Too often, those conducting research on developing country issues neglect these intergeneration effects (from grandparents to children through to their own grandchildren). Our need to understand long wave phenomena will only increase as we tackle issues such as aging, chronic disease, urbanisation and climate change. This book gives us some insights into how to do that and the value added of doing so. For example are we using short-run estimates of the responsiveness of calorie consumption to changes in income (vital in projecting food needs and potential hunger crises) when we should, as the book argues, be using time series estimates which give much lower estimates? If we did, our forecasts of the numbers of hungry people would be much lower with profound implications for public policy. Second, the book contrasts experiences from the rich and developing worlds. This does not happen nearly enough—these two worlds are quite distinct in terms of research and policy communities and yet the issues, methods and policy prescriptions are very similar and so the scope for cross-learning seems immense. For example, the evidence on how urbanisation in the 19th century in the US and UK led to declines in average male heights as disease and overcrowding overwhelmed any higher wages earned) should serve as a wake-up call to those in the development community who, in my opinion, are taking a rather casual view of the implications of urbanisation for wellbeing. Third, the book shapes the future research agenda by outlining a number of important questions, two of which stand out: (a) why does it take 2-3 generations for changes in environment to manifest as improved adult height? and (b) given that heights were not measured at the population level anywhere before the early 18th century, what will the laments of the 22nd century analysts be as to the variables we should be measuring today but have not even considered?

But the book also frustrates. It does not manage to make the most of the developed-developing country comparisons. There is not enough firepower in the writing team on the developing country literature (the evidence is over-reliant on a small number of top US academics) and so some of the opportunities to apply interesting findings from Europe and the US to the developing world (and vice versa) are missed. For example the insight about the extent to which heights can improve in one generation might explain the curious lack of response of nutrition status to sparkling economic growth in India (the book mistakenly brackets China and India’s progress in improving nutrition status). Nor does the book do enough to challenge current notions of economic growth. While effectively critiquing the partiality of income as a measure of welfare (and arguing that, as a measure, nutritional status is “analogous to measures of capability”), the book is sanguine about the capacity of current economic growth patterns to generate “bads” such as carbon emissions, obesity, and inequality. The long term perspective afforded by the intergenerational historical perspectives are also presumably the reason for the book to be very light on policy recommendations, but surely the long view places a greater obligation to think about core policy mechanisms, unencumbered by electoral cycles. At the individual level, there is a nagging worry that the authors have not sufficiently highlighted the ability of people to influence the impacts of long term trends on their bodies. The body is more than a diagnostic tool, it is the servant of our agency.

Nevertheless, this book is an authoritative summary of an evolving field of “technophysio evolution”. It places the size and shape of the human body at the centre of generational transitions. In doing so it generates new insights into contemporary development processes, even if it does understate the ability of humans to do something about the trends that affect their bodies.

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