It's no secret that life expectancy in some areas of the U.S. is higher than in others. Data from the CDC shows that on average Hawaiians live to 81, while West Virginians only see 74 birthdays. 

But why is that? Is it just that some parts of the country attract wealthier people with better access to health care and quality diets? Or perhaps active, health conscious people tend to cluster together?

If that's the case, the issue is underlying demographics. Your health outcomes are impacted by your socioeconomic status, race, genes, and habits. Moving from Mississippi to Minnesota won't change those factors and shouldn't, therefore, have much impact on how long you can expect to live

Or is it the case that the environment is driving a lot of the differences in life expectancy? If that's true, a person who moves from a low life expectancy state to a higher life expectancy state should actually live longer without changing the basic facts about who they are. 

A recent study by MIT economist Amy Finkelstein and colleagues set out to figure out how much each of these explanations accounts for the variation in life expectancy across the U.S. The results were just published in American Economic Review and they're good news for those looking to live a little longer: Moving to the right place, the researchers found, can actually add years to your life. 

Want an extra year of life? Pack up that moving van. 

To figure out the role of what researchers call "health capital" (basically how healthy the population of a particular location happens to be) from the effects of the location itself (maybe the air is cleaner or the hospitals are better, for example), the team examined the Medicare records of 6.3 million seniors aged 65 to 99. Of those six million-plus people, two million moved a significant distance during the study period. 

"The idea is to take two elderly people from a given origin, say, Boston. One moves to low-mortality Minneapolis, one moves to high-mortality Houston. We then compare how long each lives after they move," says Finkelstein, explaining the study's basic methodology. 

Crunching numbers in this way, the researchers determined that where you live as an older adult actually does have a significant impact on how long you can expect to live. 

"The results show that when a 65-year-old moves from a metro area in the 10th percentile, in terms of how much those areas enhance longevity, to a metro area the 90th percentile, it increases that person's life expectancy by 1.1 years. That is a notable boost, given that mean life expectancy for 65-year-olds in the U.S. is 83.3 years," reports MIT News

The research also showed that, when you zoom in to the details, these effects aren't even. While native-born residents of some cities, like Santa Fe, have higher-than-average life expectancies, moving to these locations doesn't seem to have big benefits to longevity. The reverse can also be true. Longtime residents of Charlotte, North Carolina, for example, aren't especially long-lived. But transplants to the city see an outsize boost in life expectancy. 

Why does moving to Charlotte or Chicago add years to your life? 

So why will you probably live longer if you pack your bags for Chicago or Charlotte? The short answer is the researchers aren't sure yet, but they're working on figuring it out. (I've covered related research into what sets global hot spots for extreme longevity apart here on before.) In the meantime, some suspect that the ease of accessing quality health care or local levels of pollution might play a significant role. 

Whatever explanation this line of research eventually uncovers, the basic lesson is useful to those thinking of relocating today. Where you choose to go actually does matter for your health, so you may want to consider whether your potential new hometown will help add or subtract years from your life. Check out this article for a handy color-coded map to help guide your thinking.