Declines in smoking are the largest drivers of mortality reduction in both subperiods, while educational upgrading is the next largest.
In view of the close association between educational attainment and health/mortality, a number of studies have investigated the extent to which educational attainment causally affects health. The leading alternative explanation of the association is that both education and health are heavily influenced by third variables, such as childhood family circumstances or personality features such as conscientiousness. The principal research design used to investigate causal pathways is to study the effect of compulsory schooling laws, treated as an exogenous variable, on the adult health of affected cohorts. Results in the United States and elsewhere are inconclusive, with some positive results scattered among many negative results. (For summaries, see Zajacovaand Lawrence [2018] and Moorthy, Figinski, and Lloro [2022].)
This research design is not ideal because compulsory schooling laws affect only a non-representative minority who would not have attended school in the absence of compulsion. What is not in doubt is that people with more schooling are more likely to exhibit healthy behaviors with respect to such factors as smoking, obesity, vegetable consumption, and seat belt use. They also have a lower prevalence of heart disease, stroke, and cancer (Cutler and Lleras-Muney 2006). And even if educational attainment were simply a proxy for an alternative set of socioeconomic circumstances, its powerful role shows that such circumstances deserve a prominent place among the variables accounting for declining mortality.