There exists a persistent and strikingly large correlation between education and health. For example, in the Netherlands, the higher educated can expect to live 20 years longer in good health compared with individuals who finished only primary school. Despite the stark correlation, studies carefully addressing causality suggest that the causal effect of education on health is much smaller than the correlation suggests (Van Kippersluis et al. 2011; Meghir et al. 2012; Clark and Royer, 2013). This apparent contradiction can be explained either by a strong effect of health on educational attainment, or alternatively by the same set of individual characteristics (e.g. time preference, cognitive ability) strongly affecting both health and educational attainment.

A recent series of papers by Conti and Heckman (2010), Conti et al. (2010), and Bijwaard et al. (2015) use birth cohort data with an extensive set of early childhood characteristics to disentangle the effect of (i) education and (ii) early childhood cognitive and non-cognitive skills, on health outcomes. The results show that for most health outcomes at least half of the association between education and health is driven by cognitive and non-cognitive abilities and early childhood social background.

The set of characteristics available in the birth cohorts used is comprehensive, and this series of papers has substantially improved our understanding of the association between education and health. However, the list of characteristics is not exhaustive. In particular, two potentially important channels are missing: (1) the effect of health on educational attainment is measured poorly by imperfect proxies such as childhood height, or is even entirely absent, and (2) the role of genes is not studied at all. That is, education and health may share a common genetic architecture, in which the same set of genes influence both education and health outcomes (biological pleiotropy). This is the hypothesis we intend to test in this project.

Recently, Boardman et al. (2014) have shown that indeed there is genetic correlation between education and health. However, as these authors rightly point out, this correlation does not shed light on the underlying mechanism. The genetic correlation does not imply biological pleiotropy, but could also occur due to mediation pleiotropy (for example, genetic factors influencing health, and in turn health influencing educational attainment).

Biological pleiotropy is best studied on the level of individual genetic variants (Solovieff et al., 2013). However, current methods seem not able to provide definitive answers here, because individual genetic variants have only limited explanatory power. Therefore, we propose two strategies to improve our understanding of the relation between health and education.

References:
Bijwaard, G.E., Van Kippersluis, H., & Veenman, J. (2015). “Education and health: The role of cognitive ability”, Journal of Health Economics, 42: 29-43.
Boardman, J.D., Domingue, B.W., & Daw, J. (2014). “What can genes tell us about the relationship between education and health?”, Social Science & Medicine, doi:10.1016/j.socscimed.2014.08.001.
Clark, D., & Royer, H. (2013). “The effect of education on adult mortality and health: Evidence from Britain”, American Economic Review, 103: 2087-2120.
Conti, G., & Heckman, J.J. (2010). “Understanding the early origins of the education-health gradient: A framework that can also be applied to analyze gene-environment interactions”, Perspectives on Psychological Science, 5: 585-605.
Conti, G., Heckman, J.J., & Urzua, S. (2010). “The education-health gradient”, American Economic Review Papers and Proceedings, 100: 234-238.
Meghir, C., Palme, M., & Simeonova, E. (2013). “Education, cognition and health: Evidence from a social experiment”, NBER Working Paper 19002.
Solovieff, N., Cotsapas, C., Lee, P.H., Purcell, S.M., & Smoller, J.W. (2013). “Pleiotropy in complex traits: challenges and strategies”, Nature Reviews Genetics, 14: 483-495.
Van Kippersluis, H., O'Donnell, O., & Van Doorslaer, E. (2011). Long run returns to education: Does schooling lead to an extended old age?", Journal of Human Resources, 46: 695-721.