The European Journal of Health Economics

, Volume 20, Issue 4, pp 543–557 | Cite as

Income distribution and health: can polarization explain health outcomes better than inequality?

  • Ying Yao
  • Guanghua Wan
  • Dongfang MengEmail author
Original Paper


Utilizing data from the China Health and Nutrition Survey (CHNS) from 1991 to 2011, we aim to analyze the effects of income distribution on two risks for chronic diseases: body mass index (BMI) and blood pressure. Unlike the previous studies, we consider two different kinds of indicators of income distribution: inequality and polarization. Different from relative inequality indicators such as the Gini index, which measure income gaps only, the recently developed polarization indicator captures group clustering and social alienation, in addition to income gaps. Our empirical results demonstrate that both BMI and blood pressure are positively correlated with income polarization, while inequality is a weaker predictor of these health outcomes. Thus, polarization, rather than inequality, should be used when analyzing the relationship between health outcomes and income distribution. We also examine the polarization-to-health transmission mechanism using mediation and moderation analytic frameworks. The results suggest that social networks mediate the effect of polarization on BMI and neutralize the effect on blood pressure.


Income distribution Polarization Inequality BMI Blood pressure China 

JEL Classification

I14 I15 D31 



This research was supported by the National Natural Science Foundation of China (71833003). The authors would like to thank the two anonymous reviewers for their constructive suggestions and comments.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Hitotsubashi Institute for Advanced Study (HIAS)Hitotsubashi UniversityTokyoJapan
  2. 2.School of EconomicsChongqing Technology and Business UniversityChongqingChina

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