Counties are the smallest unit for which mortality data are routinely available, allowing consistent and comparable long-term analysis of trends in health disparities. Average life expectancy has steadily increased in the United States but there is limited information on long-term mortality trends in the US counties This study aimed to investigate trends in county mortality and cross-county mortality disparities, including the contributions of specific diseases to county level mortality trends.

Silicon Valley residents have one of the highest life expectancy rates in the nation, with the average baby born in 1999 on track to live to 80, according to research appearing in today's edition of the journal PLoS Medicine. On average, that's eight years longer than their grandparents might live.

While most Americans enjoyed a clear jump in life expectancy from 1960 to 2000, a startling number — especially women — living primarily in the Deep South and in Appalachia actually saw a drop in life spans beginning in 1983, says a study that came out Monday.

For the first time since the Spanish influenza of 1918, life expectancy is falling for a significant number of American women. In nearly 1,000 counties that together are home to about 12 percent of the nation's women, life expectancy is now shorter than it was in the early 1980s, according to a study published today.