In a new study, researchers found while lifestyle choices and genetics go a long way toward predicting longevity, certain community characteristics also play important roles.
American communities with more fast food restaurants, a larger share of extraction industry-based jobs, or higher population density have shorter life expectancies.
The findings can help communities identify and implement changes that may promote longer lifespans among their residents.
The research was conducted by a team from Penn State, West Virginia, and Michigan State Universities.
American life expectancy recently declined for the first time in decades.
In the study, the team wanted to explore the factors contributing to this decline. Because of regional variation in life expectancy, they knew community-level factors must matter.
By analyzing place-based factors alongside personal factors, they were able to draw several conclusions about which community characteristics contribute most strongly to this variation in life expectancy.
Life expectancy refers to the length of time a person born in a given year can expect to live.
The team analyzed on a county-by-county basis how life expectancy in 2014 has changed from a 1980 baseline, using data from more than 3,000 U.S. counties.
They developed a model to determine the relationship between a dozen community variables and each county’s 2014 life expectancy.
The researchers found three additional community factors that each exert a significant negative effect—a greater number of fast-food restaurants, higher population density, and a greater share of jobs in mining, quarrying, and oil and gas extraction.
For example, for every 1% point increase in the number of fast-food restaurants in a county, life expectancy declined by .004 years for men and .006 years for women.
This represents a 15-20 days shorter life span for every man, woman, and child in a community, for each 10% point increase in fast-food restaurants in a community—or a 150-200 day shorter life span if the number of fast-food restaurants were to double.
Similarly, a 1% point increase in a county’s share of jobs in the mining, quarrying, oil and gas sectors was found to decrease average life expectancy by .04 years for men (or 15 days) and .06 years (22 days) for women.
The research also revealed several community factors that are positively related to life expectancy, including a growing population, good access to physicians, and a greater level of social cohesion.
Places with residents who stick together more on a community or social level also appear to do a better job of helping people in general live longer.
Another interesting finding was that lower population density, or living in more rural areas, is associated with higher life expectancy.
This suggests that living in large, densely-settled metropolitan areas, with all of their amenities and other advantages, comes at the expense of lower life expectancy.
The team also found exceptionally low life expectancies in the areas of the Pine Ridge and Rosebud Reservations in South Dakota.
Similar ‘cold spots’ of low life expectancy are in the arctic and interior portions of Alaska, the Deep South surrounding the Mississippi River, and in the Appalachian regions of Kentucky and West Virginia.
The research also revealed four “hot spots” of high life expectancy: a section of the Northeast spanning from Philadelphia to New England, southern Minnesota and the eastern Dakotas into Nebraska, an area in Colorado, and an area spanning central Idaho into the upper Rocky Mountains.
The lead author of the study is Elizabeth Dobis, a postdoctoral scholar at the Penn State-based Northeast Regional Center for Rural Development (NERCRD).
The study is published in Social Science and Medicine.
Copyright © 2020 Knowridge Science Report. All rights reserved.
