US life expectancy: IHME report shows US drops 21 spots in global rank

A new report from the Institute for Health Metrics and Evaluation estimates that by 2040, the United States will plummet to 64th place in the world for life expectancy. The U.S. ranked 43rd in 2016, making the change the largest drop among high-income nations.

According to the study, recently published in the journal The Lancet, Americans' average lifespan will increase, but only by 1.1 year, from 78.7 years (2016) to 79.8 years in 2040.

With an average lifespan of 82.9 years in 2016, Japan ranks first in the world and is projected to fall to second place by 2040, with Spain taking top honors.

Researchers examined a variety of factors that affect life expectancy, using data from the Global Burden of Disease study. Of the 250 causes of death included in the study of 195 countries and territories, the top six factors were high blood pressure, high body mass index, high blood sugar, tobacco use, alcohol use and air pollution.

They estimate that issues such as diabetes, chronic kidney disease, obesity and lung cancer will lead to a significant increase in deaths by 2040.

“The future of the world's health is not pre-ordained, and there is a wide range of plausible trajectories,” lead author Kyle Foreman said in a statement. “But whether we see significant progress or stagnation depends on how well or poorly health systems address key health drivers.”

The researchers concluded “the intersection of deliberate policy action, technological innovation, and careful attention to rising environmental, social, and geopolitical risks will likely shape the range of possible health trajectories in the future.”

Last month, the Atlanta-based Centers for Disease Control and Prevention also noted that overall life expectancy in the country was down, largely due to increasing deaths from drug overdoses, chronic liver disease, suicide, Alzheimer's and blood infections.