In 2016, the U.S. ranked only 43rd among 195 countries with an average lifespan of 78.7 years. In 2040, that’s only 21 years from now, Americans are forecast to drop 21 spots, to 64th, as other nations make faster gains.

The top five health drivers that explain most of the future trajectory for premature mortality are high blood pressure, high body mass index, high blood sugar, tobacco use, and alcohol use, Foreman said. Air pollution ranked sixth.

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