We all know that the rich suffer lower mortality than the poor. When correlations between socioeconomic status and health outcomes emerge, generally there is an assumption that the differences are due to disparate access to health care, or, more vaguely to the mysterious effect of low social status on someone’s health.
However, this study shows that even after controlling for the effect of socioeconomic status (the rich have higher IQs on average), IQ has a role to play; it is correlated with lower mortality. As noted above intelligence does not explain everything, but its role is unfortunately not considered all too often. If, for example, intelligence has some correlation with time preference, and time preference modulates one’s risk calculus, the causal chain which might result in disparate health outcomes is obvious.
This may be skewed by the fact that a number of physical problems can cause a lower IQ. Downs Syndrome is associated with both lower IQ and a number of physical ailments that limit life span. I imagine the same is true for things like brain damage at birth.
Is a lower IQ really related to less healthy / more self-destructive behavior? I’d certainly expect that someone with a higher IQ is more likely to be able to handle partial differential equations, but I know plenty of people who are probably at the higher end of the IQ scale who smoke, drink excessively, etc.
I would strongly suggest that you click the link and read my two posts there. The evidence documented in multiple studies (which I cited and quoted there) is extremely solid that, on average, those who have lower IQs really do make less intelligent choices that lower their lifespans significantly compared to those with higher IQs, individual exceptions notwithstanding. They smoke more often and are less likely to quit, exercise less, are more likely to be obese, are more likely to be murdered and to commit suicide, and are more likely to die an accidental death. All controlled for SES and educational level.
Whatever IQ actually measures it at least correlates with avoiding known risk factors, with having the smarts to hang out with a less violent crowd and the smarts to get themselves out of dangerous circustances without harm, and with the smarts to not overdose either by accident or on purpose, or to get too close to the edge, etc.