WASHINGTON — Women in large swaths of the U.S. are dying younger than they were a generation ago, reversing nearly a century of progress in public health and underscoring the rising toll of smoking and record obesity.

Nationwide, life expectancy for American men and women has risen over the last two decades, and some U.S. communities still boast life expectancies as long as any in the world, according to newly released data. But over the last decade, the nation has experienced a widening gap between the most and least healthy places to live. In some parts of the United States, men and women are dying younger on average than their counterparts in nations such as Syria, Panama and Vietnam.

Overall, the United States is falling further behind other industrialized nations, many of which have also made greater strides in cutting child mortality and reducing preventable deaths.

In 737 U.S. counties out of more than 3,000, life expectancies for women declined between 1997 and 2007. For life expectancy to decline in a developed nation is rare. Setbacks on this scale have not been seen in the U.S. since the Spanish influenza epidemic of 1918, according to demographers.

‘There are just lots of places where things […]