Global country-level estimates of associations between adult height and the distribution of income.

OBJECTIVES

This article presents the first estimates of global associations between adult height and the distribution of income, and considers the roles of regional heterogeneity, heterogeneity across low- and high-income countries, and of infant mortality as a potential mediator.

METHODS

Linear parametric and semiparametric regressions predicting mean height and sexual dimorphism in height are estimated using data on one cohort born in 1996 with height measured in 2016. Measurement error in income inequality is addressed using an instrumental variables method.

RESULTS

Across countries higher income per capita is strongly associated with higher mean height, and higher income inequality is associated with lower mean height after holding mean income constant. These relationships vary with mean income: at low incomes, higher mean income strongly predicts greater height but income inequality has no statistically significant effect, whereas for high-income countries, only higher income inequality predicts lower height, and only in Europe. Sexual dimorphism in height is positively associated with mean income at low incomes, but it is not related to income inequality.

CONCLUSIONS

Controlling for income inequality has modest effects on a positive height-income gradient. Greater inequality predicts lower height after holding income per capita constant, suggesting that mean height should be used with caution as a proxy for standard of living in some contexts. The extent to which these associations reflect causality running from economic conditions to height cannot be determined from these results.