THURSDAY, April 21, 2016 (HealthDay News) -- If you're an American aged 20 or under, your expected life span is now less affected by whether you're rich or poor than it used to be, a new study finds.
Researchers at Princeton University report that the life expectancy gap between rich and poor youth in the United States narrowed between 1990 and 2010.
"Our big message here is that the health of the next generation in the poorest areas of the United States has improved tremendously, likely due to social policies that helped the most disadvantaged families," study co-lead author Hannes Schwandt, an assistant professor at the University of Zurich, said in a Princeton news release.
Schwandt and Princeton researcher Janet Currie led the study, which tracked U.S. Census data from 1990 to 2010, assessing changes in life expectancy of Americans from birth.
Overall, the gap in life expectancy between rich and poor American adults rose during the study period, a finding the researchers said was consistent with previous studies.
However, the life expectancy gap between rich and poor Americans up to age 20 has declined rapidly. This finding was most pronounced in poorer counties across the United States, the researchers said.
The rate at which children and young adults of both sexes died fell rapidly, especially in poorer counties, the researchers said. This positive change accelerated for young children between 1990 and 2000, the study authors added, and there was significant improvement among older children between 2000 and 2010.
The researchers cited better health care, food and nutrition programs, and lowered pollution rates as factors that may be helping boost the health of young people.
"There have been tremendous improvements in the health of poor American children over the past 20 years," Currie said.
"One thing we hope that people will take away from this study is a sense that differences in mortality are not inevitable but are strongly mediated by policy," she added. "Health insurance, income support, anti-tobacco initiatives and reductions in pollution really do make a noticeable difference at the population level, especially at younger ages. So we hope the results will encourage policymakers to take measures that promote public health."
Life expectancy for Americans overall rose between 1990 and 2010, the study found. However, income continued to play a key role. For example, U.S. males from rich counties can expect to live six years longer than those in poor counties, the study found, and that gap is three years for females.
Schwandt had one theory about the continuing disparities.
"Smoking rates have decreased dramatically over the past 50 years, but the decline occurred first among the rich and only later among the poor," he noted. "In cohorts who entered old age during the past 20 years, the rich had largely stopped smoking while smoking rates remained high among the poor. Hence, the increasing inequality that we're currently seeing in old-age mortality may simply be the consequence of the great reduction in smoking that occurred with some lag among the poor."
The study was published April 21 in Science.
The U.S. National Institute on Aging has more about healthy aging and longevity.