Most children born today are projected to live longer than they were decades ago, but sadly, this is not the case in every place across the country.

New research indicates the lifespan gap among US counties is large and growing. The data showed a gap of 20.1 years between the counties with the longest and shortest life expectancies. A child born in 2014 in Oglala Lakota County, South Dakota can expect to live for 66.8 years, whereas a child born in the same year in Summit County, Colorado can expect to live for 86.8 years.

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“These findings demonstrate an urgent imperative, that policy changes at all levels are gravely needed to reduce inequality in the health of Americans,” Dr. Ali Mokdad, an author on the study, said in a statement. “Federal, state, and local health departments need to invest in programs that work and engage their communities in disease prevention and health promotion.”

In the study, published in JAMA Internal Medicine, the researchers calculated the life expectancy for every US county from 1980 to 2014. The average life expectancy for babies born in 2014 was about 79.1 years, which climbed a little more than 5 years from the 1980 life expectancy.

US Counties With Highest Life Expectancy

Summit County, Colorado - 86.8 years

Pitkin County, Colorado - 86.5 years

Eagle County Colorado - 85.9 years

US Counties With Lowest Life Expectancy

Oglala Lakota County, South Dakota - 66.8 years

Todd County, South Dakota - 68.5

Sioux County, North Dakota - 68.6

The researchers also looked at the risk of dying, and analyzed which risk factors, socioeconomics and race, and health care contribute to inequality.

“Risk factors like obesity, lack of exercise, high blood pressure, and smoking explain a large portion of the variation in lifespans, but so do socioeconomic factors like race, education, and income,” explained lead author Laura Dwyer-Lindgren.

All three counties with the lowest life expectancies are entirely on Indian reservations. Prior research has indicated that Native Americans have higher levels of poverty and lower levels of education than the national average, according to Pew Research Center. Other clusters of counties with low life expectancies were found in Kentucky, West Virginia, and Alabama. Many of those counties even saw a decrease in life expectancy since 1980.

In their paper, the authors note this research indicates a need for public health policies to help reverse the trend of increasing disparities in the United States.

“The inequality in health in the United States - a country that spends more on health care than any other - is unacceptable,” said Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation, where the the research was conducted. “Every American, regardless of where they live or their background, deserves to live a long and healthy life. If we allow trends to continue as they are, the gap will only widen between counties.”

See also: Life Expectancy Around The World: In Which Countries Do People Live The Longest?

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