Global effects of income and income inequality on adult height and sexual dimorphism in height

Abstract

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...

The regulation of human growth includes an understanding of competitive growth strategies and community effects on height

“…This is an interesting paper. It nicely reviews common concepts of understanding the regulation of human growth and clearly states the objectives of this work as “to evaluate the effect of height on life satisfaction.” The authors’ “main finding is that height does have a strong positive effect on life satisfaction”; and they conclude that their “findings suggest that height is important in explaining life‐satisfaction independent of other well‐known determinants.” These statements perfectly fit into current knowledge, and they repeat the current understanding of causality in the association between height and life satisfaction: The taller, the better; and size is beautiful, at least in terms of marriage and earnings (Bogin, Scheffler, & Hermanussen, ).…”

Stunting, starvation and refeeding: a review of forgotten 19th and early 20th century literature

“…There was poor sanitation, unreliable food supply and food storage to be sure, but there was also great economic inequality, undemocratic politics, lack of education for the poor and exposure to much violence for poor and rich, similar in many essential ways to least developed nations today. All of these physical, social and political factors are associated with shorter height for the people who most suffer, and shorter average height for the population as a whole . We return to this point later in this Discussion.…”

Nordic populations are still getting taller – secular changes in height from the 20th to 21st century

“…The overall economic situation, including both income and social equality, are of importance for optimal height within a population . The Nordic countries have general welfare systems and relatively high economic and social equality compared with other countries.…”