New research has revealed that life expectancy for the least-educated white Americans has been on the decline – falling by four years since 1990, the New York Times reported.

While trends have shown that the most educated Americans have been continually increasing in life expectancy, four recent studies have revealed small declines in mortality.  This most recent study – out of the University of Illinois at Chicago – looked specifically at those who did not have a high school diploma, and whites showed the sharpest decline.

Further analysis of mortality data showed that white women lacking a diploma had the biggest decline – losing five years of life between 1990 and 2008, according to the New York Times.  In contrast, the life expectancy for black women without a high school diploma had exceeded that of their white counterparts since 2008.

S. Jay Olshanksy, public health professor at the University of Illinois and lead investigator, said that he and his colleagues do not exactly know why they saw these trends, but they have a few theories.  They cited the recent rise in prescription drug overdoses among whites, the fact that less educated whites have higher smoking rates, the obesity epidemic and the continual increase of less educated people lacking health insurance, the New York Times said.

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