Where you live affects your happiness and health, but how exactly?

The Philadelphia skyline is seen along the banks of the Delaware River, Wednesday, Oct. 18, 2017. (Matt Rourke/AP Photo)

The Philadelphia skyline is seen along the banks of the Delaware River, Wednesday, Oct. 18, 2017. (Matt Rourke/AP Photo)

Every year, Gallup and Sharecare rank U.S. cities for well-being, based on how residents feel about living in their communities, and their health, finances, social ties and sense of purpose. Perhaps unsurprisingly, places like Naples, Fla., and Boulder, Col., tend to top the list, while Southern and Midwestern towns including Canton, Ohio, and Fort Smith, Ark., often come in last. But what hard data underpin the differences between these communities?

A study published Wednesday takes a step toward teasing out which attributes might contribute to well-being in communities around the country.

A Yale-led team of researchers has identified 12 community factors independently related to well-being. The factors included some obvious ones, such as higher levels of education and income, as well as some surprises, including a higher percentage of black residents, a higher percentage of bicycle commuters, and better access to preventive care, such as mammograms. The results appear in the journal PLOS ONE.

Well-being has been associated with longer life expectancy and better health outcomes. Previous studies have also shown that where someone lives can improve or diminish well-being.

For this study, the researchers compared two types of data: well-being data, gleaned from the Gallup-Sharecare Well-Being Index, based on surveying more than 300,000 Americans; and community attributes that researchers suspected would influence well-being drawn from the Robert Wood Johnson Foundation County Health Rankings, as well as other sources. This data included county-level information on high school graduation rates, percent of children in poverty, and the number of preventable hospital stays, among other things.

Using a statistical model, researchers whittled down more than 75 community attributes to determine which stood out.

Many of the potential factors are highly correlated with one another — for example, lower median income is correlated with lower education and less access to healthy food. Researchers wanted to figure out which characteristics measurably affected well-being independent of those other factors.

To the researchers’ surprise, they discovered that just 12 factors related to demographics, clinical care, social and economic factors, and the physical environment explained over 90 percent of the variation in well-being across the country.

“That’s higher than I would have expected,” says Brita Roy, assistant professor of medicine at the Yale School of Medicine and lead author of the study.

In what Roy called an unexpected but notable result, her team found that communities with higher percentages of black residents reported higher levels of well-being.

“Having something that shows greater diversity is actually better for all of us I think is a really important finding,” Roy says.

Research by Carol Graham at the Brookings Institution and others has shown high levels of optimism within the black community, which could account for the correlation in the paper.

But percentage of black residents is not the same as an overall measure of diversity, says Anita Chandra, director of RAND Justice, Infrastructure, and Environment. A better measure of diversity is diversity exposure, which calculates how one ethnic or racial group is situated and exposed to all the other groups in a community.

Another unexpected finding was the connection between well-being and the percentage of residents commuting by bicycle. People living in places where they could commute to work by bike reported feelings of satisfaction and fulfillment.

This could be because places with bike-friendly infrastructure might also support other types of policies that improve living in that area. Or it could be that commuting by bike improves physical health, which in turn improves a sense of well-being; a study in Heart this week showed walking or cycling to work cut the risk of dying from heart disease or stroke by 30 percent.

The researchers hope their findings could lead to future research and even policy applications.

“We are starting to move in the direction of trying to understand at the community level how we can actually work to improve well being for all members of the community,” says Roy.

The study had limitations. It was cross-sectional, meaning researchers used one snapshot in time to see what was linked together, rather than using data over time. “We can’t prove causality at this point,” Roy says. “We don’t know if we improve these twelve factors, will we actually lead to improved well-being. But it certainly provides us with a first step in understanding what perhaps we should test.”

The study also didn’t include psychosocial data, such as levels of trust in community, trust in government and social cohesion. Those data weren’t available.

Chandra says this study serves as a call for collecting more and better information to help us grasp the full picture of what impacts wellness. “We collect a lot of data, but we still have these gaps in our understanding of community and individual well-being,” Chandra says.

She says in addition to surveys that measure an individual’s sense of well-being, like the Gallup-Sharecare index, researchers need to gather information on larger scale community and civic well-being to bring everything together.

“That’s really where policy makers and practitioners can make decisions about resource allocation and where to put time and investment and policies in place,” she says.

Nevertheless, she says this study is another important piece of the puzzle in understanding what drives overall health.

“There are things that communities can do that make it more possible for people to feel more positive about their community,” she says. “And some of these things are very much in our control.”

Dana Bate is a health and science reporter living in Philadelphia. You can follow her on Twitter: @danabate.

Copyright 2018 NPR. To see more, visit http://www.npr.org/.

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