We are often told that Chicago is “a tale of two cities,” a place where the wealthy and the poor, black and white, the haves and have-nots, live on opposite sides of town and rarely mingle outside the tight boundaries of race, class and neighborhood.

Sadly, then, we weren’t surprised at news that emerged last week: Chicago has the largest life expectancy gap between neighborhoods in the country, according to research done at New York University School of Medicine.

A stunning 30-year gap.

We were surprised, no, but deeply troubled to learn that people who live in impoverished, mostly black Englewood can expect to live until 60 — not even reaching retirement age — while people who live in high-end, mostly white Streeterville can expect to live essentially another lifetime, to 90.

That 30-year gap is yet another sign of the high price Chicagoans pay for decades of entrenched segregation and inequality. If you live in one part of town, you can expect to see your grandchildren grow up, and maybe even welcome a great-grandkid or two.

But if you live in another part of town, good luck in beating the odds and being around long enough to see your own kids make it through college.

Chicago was the starkest example of the disparities in life expectancy found by NYU researchers. But several other cities were close behind, and the study generally found that cities with the highest levels of racial and ethnic segregation also suffer from the biggest gaps in life expectancy.

Close on Chicago’s heels are Washington, D.C., with a life expectancy gap of 27.5 years; New York City, 27.4 years, and New Orleans and Buffalo, each with gaps of 25.8 years.

The problem goes beyond lack of access to health care, as one Rush University doctor made clear in an interview with WTTW. Whether a person lives to 90 or dies at 60 also depends on the social and economic conditions in a community, such as good schools, well-paid jobs, low crime rates and even access to grocery stores and places to exercise.

“Social conditions themselves create these terrible gaps in disease and premature mortality,” David Ansell, a physician and senior vice president for community health at Rush University, told WTTW.

To close the gap, Chicago must “dig deeper” into the social conditions that helped create it, as one NYU researcher urged city leaders across the country to do.

Dig deeper to find solutions. Move past the tendency to shrug our shoulders, weary of yet another story about our city’s sorry legacy of segregation.

Take steps to make Chicago a thriving, vibrant global city, where everyone has a chance to live a long, healthy, productive life.

We saw welcome signs of that kind of “digging deeper” last week, when Chicago’s aldermen held a surprisingly thoughtful discussion about affordable housing during a confirmation hearing for the city’s new housing commissioner. At last, perhaps, elected city officials are getting serious about making sure that working-class and lower-income people can find a decent place to live without forking over half their pay.

We hope to see more “digging deeper” down the road, too. On curbing violence, it goes without saying. On improving schools, so that children in low-income neighborhoods can get a good education and go on to college, just like children in more privileged circumstances. And on creating jobs, too, so that neighborhoods left to languish during decades of disinvestment thrive and help grow the city’s economic base.

The story of Chicago is that folks on one side of town die a full 30 years earlier, on average, than folks on another side of town.

We can rewrite the story.

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