Recent evidence using compulsory schooling laws as instruments for education suggests
that education has a causal e§ect on mortality (Lleras-Muney, 2005). However,
little is known about how exactly education a§ects health. This paper uses compulsory
schooling laws to try to identify how education impacts health and to indirectly
assess the merit of using these laws to infer the causal e§ect of education on health.
I Önd that previous Census mortality results are not robust to the inclusion of statespeciÖc
time trends but that robust e§ects of education on general health status can
be identiÖed using individual level data in the SIPP. However, the pattern of e§ects
for speciÖc health conditions in the SIPP appears to depart markedly from prominent
theories of how education should a§ect health. I also Önd that vaccination against
smallpox for school age children may account for some of the improvement in health
and its association with education. These results raise concerns about using early
century compulsory schooling laws to identify the causal e§ects of education on health.