Since two replies to this comment suggest the underlying cause might be " less toxic environments, better ecology (less polluted, less crowded areas - less infe

Since two replies to this comment suggest the underlying cause might be " less toxic environments, better ecology (less polluted, less crowded areas - less infections, less harards, etc)" and " better health care", the answer is no. According to the original paper, life expectancy in the lowest quartile "were not significantly correlated with access to medical care, physical environmental factors, income inequality, or labor market conditions." https://jama.jamanetwork.com/article.aspx?articleid=2513561 https://jama.jamanetwork.com/article.aspx?articleid=2513561 The big correlates seem to be income and behavior (e.g. smoking, obesity).