In a study of over 250,000 individuals using genome-wide data, the study was able to identify 697 variants that determine an individuals height. In a population with perfectly equal access to nutrition and health resources, height distribution would only reflect genetic variation. Unequal access to these resources within a population means that wealthier individuals could have better health and nutrition, and therefore tend to grow taller than poorer ones; variance of heights therefore becomes larger. In other words, resource-based variance due to income inequality is added to genetic variance, widening the distribution of heights. Some empirical evidence across a range of contexts would support this hypothesis. Animal proteins form an increasingly large part of our diets as income increases. Since nutrition plays a key role in determining height, there is an obvious relationship between income and height. 33

So, both genetic and environmental factors have an impact on height variation. But which is the most important determinant? The relative contribution of genetic factors to differences in heights within populations is defined as ‘heritability’. Heritability is measured between 0 and 1; the higher the heritability, the larger the contribution of genetics. Twin and adoption studies typically estimate heritability at about 0.8. 48 Differences in height within a population are not only influenced by genetic variance. Greater environmental variance within a population is also reflected by a wider distribution of heights. The distribution of heights has therefore be used as one indicator of socioeconomic inequality in the past. 43

FAQ

Grasgruber, P., Sebera, M., Hrazdíra, E., Cacek, J., & Kalina, T. (2016). Major correlates of male height: A study of 105 countries. Economics & Human Biology, 21, 172-195. Headey, D., Hirvonen, K., & Hoddinott, J. (2018). Animal sourced foods and child stunting. American Journal of Agricultural Economics, 100(5), 1302-1319. These might actually be the very last charts available printed by the original printers, Wood Richardson in York.

Komlos, J., & Lauderdale, B. E. (2007). The mysterious trend in American heights in the 20th century. Annals of human biology, 34(2), 206-215. Underweight: You are below the standard defined in the chart. You must seek professional medical help to find the reason and remedy for it.The height and weight chart is a useful indicator of overall health but as we have seen it has shortcomings as well. One cannot rely on BMI alone to assess health. This is based on the assumption that evolution is a very slow process that takes thousands of years to occur; the pace of evolution does vary, however. However, you have not added up firstly your age, secondly other factors like bone, muscle, and fat content in your body composition.

Regionally, the standard deviation of male heights is largest in North America and Australia, at 7.49 cm, and smallest in East Asia, at 6.37 cm. The pattern is the same for women, with 6.96 cm in North America and Australia, and 5.74 cm in East Asia. Some of the distribution of heights within a population is likely to reflect the degree of genetic variance. 42 How does environment and living standards affect the distribution of heights? The relationship between health and height is reinforced by the significant impact of healthcare expenditure. We see this reflected in Arab states where health expenditure is much lower than their income level would predict. For example, compare Oman and the Netherlands: the average male height of the Dutch is 182cm – 13 centimeters taller than the average in Oman. Both countries have high levels of income per capita. But the Netherlands spends much more on healthcare: healthcare expenditure in Oman is 4.0% of gross domestic product (GDP) versus 10.1% of GDP in the Netherlands. Growth plates are easy to identify on an X-ray because they are softer and contain less mineral content than standard bone. That makes them appear darker than the rest of the skeleton on the X-ray image. They look different at each age – thanks to that, a doctor can determine bone maturity by simply reviewing its appearance. Then, the image is compared with the closest matching image from an atlas. Now that you know about it, you are in a better position to understand the kind of medical conditions you are likely to invite due to unhealthy weight.In the 19th century, North Americans were the tallest in the world, but fell behind over the course of the 20th century. The study attributes this partly to nutrition, arguing that “there are reasons to believe that US diets are deficient to some extent as nearly a half of households' food expenditure is spent on food outside of the home. 15 This is troubling insofar as meals consumed outside of the home are less balanced than those consumed at family dinners. 16 It also highlights “differences in the socio-economic and health systems of the West and Northern European welfare states and the more market-oriented economy of the USA”, arguing that “socio-economic inequality in America is much greater than in Western Europe and inequality has a negative effect on mean height. 17 Furthermore, the West European welfare states, in which a subsistence income is more or less guaranteed, provide a more comprehensive social safety net including unemployment insurance and a comprehensive health-insurance coverage.” 18 Why has average human height in Sub-Saharan Africa fallen? The global mean height of adult men born in 1996 is 171 centimetres (cm), or 5 foot and 7.5 inches. There are large variations in average height between nations: the shortest being men in Timor at 160 cm, and the tallest from the Netherlands at 182 cm. This represents a range of 22 cm, or 8 inches. Nosworthy, M. G., Neufeld, J., Frohlich, P., Young, G., Malcolmson, L., & House, J. D. (2017). Determination of the protein quality of cooked Canadian pulses. Food science & nutrition, 5(4), 896-903. Grasgruber, P., Cacek, J., Kalina, T., & Sebera, M. (2014). The role of nutrition and genetics as key determinants of the positive height trend. Economics & Human Biology, 15, 81-100.