In the early postwar period, improvements in life expectancy in many Western countries made health authorities, health scientists and politicians believe that social differences in mortality converged. The assumption was that inequality, when measured as death rates, was on steady decline, possibly even on the brink of disappearing. The question is then, how far back in time can social differences in mortality be traced? Can they be traced back to the agricultural society or are they a result of industrialization? Whether or not these differences are the result of the industrial revolution became a lively debated issue at the time and has continued to be discussed to date. While many scholars have taken a Malthusian view, that mortality in the past was largely determined by economic factors, others argue that mortality was determined by non-economic factors, leaving little room for a social gradient in mortality. Due to lack of coherent data covering long time periods, our knowledge has been based on bits and pieces of evidence from various locations and time periods. The evidence used is not only fragmentary but furthermore only partly comparable as different definitions of social class and mortality have been used.
Here we present results from seven new studies of locations in Western and Southern Europe, the US and Canada for which individual-level longitudinal data exists during the industrialization period. Most of these studies cover also the first part of the twentieth century, a period for which such microdata hitherto has largely been lacking. Taken together, they have a wide geographic coverage and a very long time horizon. Based on these studies, we argue that social differences appeared both long before and long after the industrial breakthrough, in both cases implying that these differences are not directly related to industrialization. We also argue that the association between income and mortality observed today most likely is a recent phenomenon. Overall, a causal link between income and mortality is put into question.
► Based on seven studies from the pre-industrial period until today we show that upper classes have no constant mortality advantage. ► The perception that industrialization caused a social gradient in mortality is also emphatically questioned. ► Overall, a consistent causal link between socio-economic position and mortality is open to serious doubt.
Keywords: Adult mortality; SES differentials; Life expectancy; 18th–20th century; Europe; North America; Inequality; Living conditions