The Centers for Disease Control and Prevention revealed that there are 70,000 more deaths in 2017 than the previous year, with 2.8 million deaths total.
In 2017, Americans overall could expect to live to 78.6.
"We're seeing the drop in life expectancy not because we're hitting a cap [for lifespans of] people in their 80s".
"We're a developed country, we have a lot of resources, we should have increasing life expectancy, not decreasing life expectancy", he added. It was the most deaths in a single year since the USA government began counting more than a century ago.
Drug overdoses increased to 70,237 in 2017, compared to 63,632 the year before, the government stated in an accompanying report.
The heroin overdose death rate remained constant at about 5 deaths per 100,000 people for both 2016 and 2017; that said, it is seven times higher than in 1999.
"Life expectancy gives us a snapshot of the nation's overall health and these sobering statistics are a wakeup call that we are losing too many Americans, too early and too often, to conditions that are preventable", CDC director Robert Redfield said. And it is thanks in large part to increases in drug overdose death and suicide, according to supplementary reports simultaneously released by the CDC. It is the third straight year life expectancy in the U.S. has declined or stayed flat, reversing course after decades of improvement.
The 2017 decline was due to a drop in life expectancy among men, who saw their estimated life expectancy at birth decline from 76.2 years in 2016 to 76.1 years in 2017.
The figures mark an "appalling performance not seen in the United States since 1915 through 1918", the Washington Post reported.
Barring the unusual experience of the early 20 century, "we've never really seen anything like this", said Robert Anderson, a CDC official.
What are some other reasons?The life expectancy figure is based on current death trends and other factors.
The age groups particularly affected in 2017 spanned the 25-34 range, as well as 35-44 and 54-54. The rate increased from about 6 overdose deaths per 100,000 people in 1999 to almost 22 per 100,000 in 2017. These are, in order of most to fewest deaths: heart disease, cancer, unintentional injuries, chronic lower respiratory diseases, stroke, Alzheimer's disease, diabetes, influenza and pneumonia, kidney disease, and suicide. But increases in cocaine overdoses (especially among African Americans) and methamphetamine overdoses are also driving up death rates. Suicide is the tenth leading cause of death in the United States for the tenth year in a row.
Between 2016 and 2017, suicide rates increased by 3.7 percent. The age-adjusted rate of suicide among females increased from 4.0 per 100,000 in 1999 to 6.1 in 2017, while the rate for males increased from 17.8 to 22.4.
Urban-area suicide rates were 16% higher in 2017 than 1999, and rural-area suicides increased by 53% over the same time period.
Anderson said provisional data for the first four months of 2018 show a plateau and possibly a small decline in drug overdose deaths.