Where to live is a critical question for the retirement years.

For decades the answer seemed to be move somewhere warm. Retirement and living in a sunshine state are almost synonymous in popular culture. The nation's fastest-growing metropolitan area over the past decade was The Villages, a retirement community in Florida, new Census Bureau data shows.

The reality has long been that most retirees choose to "age in place" or "age in community" (the catchphrase I prefer). Aging in place often involves staying in your current home. But aging in place can also mean choosing to stay in a community or region. The alternatives include downsizing into a smaller home, joining a continuing care community, and living in a multigenerational home.

The primary draw of aging in community is to remain close to friends and family. Retirees who want to keep earning an income also find it easier to get work by tapping into the local network they've built.

A recent scholarly paper adds another factor to weigh: The impact of the local environment on mortality risk. In "Place-Based Drivers of Mortality: Evidence of Migration," three economists find that moving to certain locations during the Medicare years can affect life span.

"The idea behind our approach is to take two patients from the same origin (say, Boston), one of whom moves to a low-mortality area (say, Minneapolis), and the other of whom moves to a high-mortality area (say, Houston); and to compare their mortality outcomes after they move," write economists Amy Finkelstein (MIT), Matthew Gentzkow (Stanford) and Heidi Williams (Stanford).

They found on average that when a 65-year-old moves from a metro area with lower-than-average longevity into a metro area with higher-than-average longevity, a person's life expectancy can increase by 1.1 years.

That's a big jump considering average life expectancy for 65-year-olds in the U.S. is 83.3 years.

I've only pulled one strand from their much broader scholarly study. Their research highlights the importance of taking an environmental scan when deciding whether to leave the state or stay, especially judgments about the quality of medical care and the quality of everyday life.

While this isn't a brief against relocating somewhere warm, it's disturbing that a large swath of the Southern and Southwestern U.S. showed negative effects on longevity. Mortality risk is one more factor to consider while exploring your options during retirement.

Chris Farrell is senior economics contributor for "Marketplace" and economics commentator for Minnesota Public Radio.