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The changing body. Health, nutrition and human development in the western world since 1700. Bernard Harris 30 June 2011. Caption for the image should be placed in a clear area on the image to ensure it is legible. Introduction.
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The changing body Health, nutrition and human development in the western world since 1700 Bernard Harris30 June 2011
Caption for the image should be placed in a clear area on the image to ensure it is legible
Introduction • How has human health changed in the western world since circa 1700? • Why has it changed? • What are the consequences of these changes?
Measuring changes in human health:the importance of height • ‘A child’s growth rate reflects, perhaps better than any other single index, his [sic.] state of health and nutrition; and often indeed his psychological situation also. Similarly, the average values of children’s heights and weights reflect accurately the state of a nation’s public health and the average nutritional status of its citizens, when appropriate allowance is made for differences, if any, in genetic potential…. A well-designed growth study is a powerful tool with which to monitor the health of a population, or to pinpoint subgroups of a population whose share in economic and social benefits is less than it might be. Indeed, as infant mortality rate goes down during a country’s development, so the importance of monitoring growth rate increases’ (P.B. Eveleth and J.M. Tanner, Worldwide variation in human growth, Cambridge: CUP, 1990, p. 1).
Technophysio evolution • ‘The theory of technophysio evolution rests on the proposition that, during the last three hundred years, particularly during the last century, humans have gained an unprecedented degree of control over their environment – a degree of control so great that it sets them apart not only from all other species, but also from all previous generations of homo sapiens’ (R. Fogel and D. Costa, ‘A theory of technophysio evolution, with some implications for forecasting population, health care costs and pension costs’, Demography, 34 (1997), 49-66 (at p. 49)).
Anthropometric history • The conscripts of 1868 (Le Roy Ladurie et al., 1968, 1971, 1979) • The economics of mortality in North America, 1650-1910 (Fogel et al., 1978, 1982) • Height and the standard of living (Floud 1984; Steckel 1992)
Changes in stature in Britain:Adults Source: R. Floud, K. Wachter and A. Gregory, Height, health and history, Cambridge: CUP, 2011, p. 154.
Changes in stature in Britain:Children Source: R. Floud, K. Wachter and A. Gregory, Height, health and history, Cambridge: CUP, 2011, p. 166.
Changes in stature in Britainin international context (Mature height, in cm)
Life expectancy Notes: The most recent figures for Iceland and the Netherlands refer to the period 2000-08 rather than 2000-09. Source: http://www.mortality.org/ (accessed 7/6/11)
Real wages Notes. The data for ‘Feinstein (original series)’ are his estimates for real earnings adjusted for unemployment in Great Britain. These figures have been modified in the light of Allen’s revised consumer price index to produce the estimates in ‘Feinstein (adjusted series)’. Sources: Wrigley and Schofield 1981: 642-4; Feinstein 1998: 648, 652-3; Allen 2007: 36.
Food availability • Domestically-produced cereals and pulses • + other domestically-produced foodstuffs • + imported foodstuffs
Domestic production of cereals and pulses • Land under cultivation (1700, 1750, 1800, 1850) • Yield per crop per acre • Amount available for human consumption • Total – (seed + animal feed + milling + distribution) • Energy values
Composition of diet Table 4.10. Sources of calories, by food group, in England and Wales, 1700-1909-13. Notes. We have calculated that the average daily consumption of ‘cottage produce’ in 1909-13 was equal to 135 calories per head. The Royal Society estimated that the total number of calories from this source was equivalent to one-half of the calories obtained from home-produced poultry, eggs and vegetables, and one-third of the calories obtained from home-produced fruit. We have used these figures to estimate the proportion of the calories derived from ‘cottage produce’ which may be allocated to each of the other categories. For further information, see Parliamentary Papers 1917: 7. Sources: See Tables 4.7-4.8.
Other causes of health improvement • Disease virulence (scarlet fever; tuberculosis?) • Housing • Environmental improvement • Sanitary reform • Immunisation campaigns • Therapeutic interventions
Cohorts and mortality decline Source: Kermack, McKendrick and McKinlay 1934: 699.
Food and economic development Basal metabolism Calories Physical Activity Level (1.27BMR) Work and other activity
Food and economic development, cont. Notes: PAL means a person’s daily activity level as a multiple of BMR. It is assumed that the log of BMI is normally distributed with mean 21 and standard deviation 3 [BMI~LN (21, 3)], and that stature is normally distributed with mean 1.68 meters and standard deviation 0.066 meters [Stature~N (1.68, 0.066)]. Column 4: Col. 2 × (Col. 3 squared), Column 5: computed from Equation (A.7), Column 6: The size distribution of calories is from Column 4 in Table 2.4, and Column 7: Col. 6 ÷ Col. 5. Note that some figures are subject to rounding. Source: Floud, Fogel, Harris and Hong 2011: 73
Food and economic development, cont. For notes and sources, see Floud, Fogel, Harris and Hong 2011: 167, 169.
They're taller, better fed and have fewer fillings - so why are today's children LESS healthy than 50 years ago?(Daily Mail, 7/6/11) http://www.dailymail.co.uk/health/article-1395040/Theyre-taller-better-fed-fewer-fillings--todays-children-LESS-healthy-50-years-ago.html
Conclusions and implications • Increases in average height reflect improvements in basic aspects of the standard of living, such as diet and environmental conditions • They are also associated with parallel improvements in infant and child survival rates • All of these improvements have contributed to economic growth in Britain and other countries and, consequently, to the welfare of succeeding generations • They also have long-lasting implications for adult health and longevity (see e.g. Barker and Osmond 1986, etc.)
Conclusions and implications, cont. Comparison of the prevalence of selected chronic conditions among Union Army veterans in 1910, veterans in NHIS, 1985-8, and veterans in NHIS, 1997-2006 Source: Floud, Fogel, Harris and Hong 2011: 345.
Conclusions and implications, cont. • Supplemental Figure 2. Male (blue squares) and female (red circles) life expectancy in the record-holding country, based on the annual data shown in supplementary table 1. For males the fitted line has a slope of 0.222 and r2 = 0.980 Source: J. Oeppen and J. Vaupel, ‘Broken limits to life expectancy: Supplementary material’, Science, 10 May 2002 (http://www.sciencemag.org/content/296/5570/1029/suppl/DC1).