And the people living shorter lives don't just include poorer people. Middle-income people in deeply unequal societies live shorter lives than middle-income people in more equal societies.
What can explain how inequality makes this deadly impact? We don't know for sure. But many epidemiologists scientists who study the health of populations point to the greater levels of stress in deeply unequal societies. That stress wears down our immune systems and leaves us more vulnerable to a wide variety of medical maladies.
We have, of course, no pill we can take to eliminate inequality. But we can fight for public policies that more equally distribute America's income and wealth. Other nations have figured out how to better share the wealth. Why can't we?