Life expectancy for U.S. men slipped for a third straight year, according to new data from the National Center for Health Statistics.

The average male lifespan stood at 76.1 years in 2017, a four-month decline since 2014.

Drug overdose rates for men are almost twice as high as a decade ago.

Life expectancy for American men dropped for a third consecutive year, with the National Center for Health Statistics citing an increase in so-called "deaths of despair," such as the rise in drug overdose deaths.

The average lifespan of men in the U.S. dipped to 76.1 years in 2017 (the latest data available), amounting to a four-month decline in life expectancy since 2014. The findings shed additional light on economic research into the sharp increase in recent years in deaths from overdoses and suicides among white men with less education.

In 2017, the life expectancy at birth for males was 76.1 years. Life expectancy at birth for males has decreased each year since 2014. For more data on life expectancy #HealthUS #lifeexpectancy https://t.co/lKhXRC5GvK pic.twitter.com/W4bpfoED1B — NCHS (@NCHStats) October 30, 2019

Princeton economists Anne Case and Nobel laureate Angus Deaton first highlighted the issue in 2015 with their research on how white, less-educated Americans had veered off track. In 1999, the mortality rate for this demographic was about 30% lower than those of African-Americans. But by 2015, their mortality rate had eclipsed that of blacks by 30%, the economists found. The reason? A spike in death rates due to alcohol and drug poisoning, suicide, and alcoholic liver disease and cirrhosis.

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The new data from the National Center for Health Statistics underline the scale of the problem. Drug overdose deaths for males over age 15 has almost doubled over the last decade, the agency found, rising to 29.1 deaths per 100,000 men in 2017, from 14.9 deaths per 100,000 in 2007.

"The recent increases were especially pronounced among men aged 25–34 and 35–44," the NCHS report noted. "From 2013 to 2017, the drug overdose death rate increased by an average of 18.5% per year among men aged 25–34 and by an average of 18.8% per year among men aged 35–44."

America is an outlier

Unlike other industrialized countries, the U.S. is seeing a plateau or decline in life expectancy, making it an outlier since higher health expenditures are typically tied with longer lives. One theory attributes that to different health outcomes for rich and poor households, an issue that has been exacerbated by rising income inequality in the U.S.

Wealthier Americans are more likely to live into their 70s and 80s than people in the middle class and the poor, according to a September report from the U.S. Government Accountability Office. In other words, being poor can be hazardous to your health.

And that can lead to significantly different life expectancies, according to a recent Harvard analysis of 15 years' worth of IRS data. Men who are among the richest 1% of Americans live almost 15 years longer than those who are in the poorest 1%, the Harvard analysis found. The gap was about 10 years for the richest versus poorest women.

Poor Americans are more likely to skip or delay health care treatment because of cost, the NCHS study said. It's an issue that impacts about 1 in 6 Americans who live at or below the poverty line, the study found.

Young women are also experiencing a sharp uptick in drug overdoses, although the rate remains lower than that seen among men, the NCHS noted. The drug overdose death rate for women over age 15 jumped 64% from 2007 to 2017, hitting 14.4 deaths per 100,000 women, it added.

Life expectancy for women, black and Latino residents has held steady since 2014, the agency said.