The last century brought increases in life expectancy in the U.S., but the trend is leveling off, a new study says.
Researchers analyzed data going back to 1930, and projections through 2055. Results showed that the average life expectancy for an American born today is 78.49 years, and that number will rise by about three years by 2055, the researchers said.
In 1900, life expectancy in the U.S. was 47.3 years, in 1930 it was 59.85 years, and it rose to 77.7 years by 2006, according to the study.
The data also showed a five-year gap between the life expectancies of well-off and the poor in the U.S. One possible reason for this is that those with low income often cannot pay to treat chronic conditions that may lead to earlier mortality, the researchers said.
“Life expectancy is dramatically impacted," by income, said study researcher Justin Denney, an assistant professor of sociology at Rice University in Texas.
The overall increase in life expectancy was not due a steady rise during the 20th century, the researchers said.
"When broken down, these numbers show that those gains were mostly experienced between 1930 andthe 1950s and 1960s,” Denney said. "Since that time, gains in life expectancy have flattened out," he said.
The study also showed that life expectancy in the U.S. lags behind other developed countries, trailing the world’s highest expectancy of 89.68 years in Monaco, and Japan, where life expectancy is 83.91 years.
The researchers based their analysis on data from the Human Mortality Database, which is administered by researchers at the University of California, Berkeley and the Max Planck Institute for Demographic Research in Germany.
The study will be published in an upcoming issue of the journal Social Science Quarterly.
Pass it on: Well-off Americans live five years longer than the underprivileged.
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