A sweeping new study led by researchers at the Yale School of Public Health (YSPH) reveals striking disparities in life expectancy across U.S. states and the District of Columbia over the past century. The study provides new insights into how public health policies, social conditions, and environmental factors appear to have fundamentally shaped Americans' longevity based on where they live. Their findings paint a sobering picture: while some states saw dramatic gains in life expectancy, others, particularly in the South, experienced little or no improvement over an entire century. "For females born in some Southern states, life expectancy increased by less than three years from 1900 to 2000," said the study's lead author Dr. Theodore R. Holford, PhD '73, Susan Dwight Bliss Professor Emeritus of Biostatistics at YSPH. That's a staggering contrast when you consider that in states like New York and California, life expectancy rose by more than 20 years over the same period.