Objectives: Average adult height of a population is considered a biomarker of the quality of the health environment and economic conditions. The causal relationships between height and income inequality, are not well understood. We analyse data from 169 countries for national average height of men and women and national level economic factors to test the two hypotheses: 1) income inequality has a greater association with average adult height than does absolute income; 2) neither income nor income inequality has an effect on sexual dimorphism in height. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 F o r P e e r R e v i e w 2 include Gross Domestic Product (GDP), Gross National Income per capita adjusted for personal purchasing power (GNI_PPP), and income equality assessed by the Gini coefficient calculated by the Wagstaff method.
MethodsResults: Hypothesis 1 is supported. Greater income equality is most predictive of average height for both sexes. Greater per capita purchasing power explains a significant, but smaller, amount of the variation. . National GDP has no association with height. Hypothesis 2 is rejected. With greater average adult height there is greater sexual dimorphism.
Conclusions:Findings support a growing literature on the pernicious effects of inequality on growth in height and, by extension, on health. Gradients in height reflect gradients in social disadvantage. Inequality should be considered a pollutant that disempowers people from the resources needed for their own healthy growth and development and for the health and good growth of their children.
-----------------------------------------This article is derived from the 2016 Human Biology Association Plenary Session titled "Worldwide variation in human growth -40 years later." The title of the symposium is taken from the 1 st and 2 nd editions of books of the same title by PhyllisEveleth and James Tanner (Eveleth & Tanner 1991). Contributions to the symposium were meant to update the topics included in Eveleth and Tanner's books.The purpose of this article is to update and evaluate worldwide variation in economic and social factors that influence the biology of adult height. We analyze national level data for measured heights for the year 1996 of men and women in 169 countries.We conduct the analysis based on two hypotheses: 1) that income inequality has a greater association with average adult height than absolute income, and 2) that sexual dimorphism in adult height remains fairly constant under different conditions of income and income inequality. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 In the present analysis we employ as measures of income the national GDP (to...