Education may be the “best predictor of who will live longest”, research suggests.
Life expectancy has been on the decline in the US.
It peaked in 2014, when the average American lived to 78.8.
Lifespan has since decreased, with most making it to 78.5 in 2017.
Officials blame this on everything from inaccessible healthcare to drug addiction.
To learn more, scientists from Yale looked at race and education - two factors “most often linked to life expectancy”.
The team analysed more than 5,000 people across four US cities who took part in the Coronary Artery Risk Development in Young Adults study when they were in their 20s.
The participants were followed for up to 29 years, during which time 395 died.
Results, published in the American Journal of Public Health, suggest education “is the best predictor of who will live the longest”.
Of those who died, around 13% had “a high school degree or less”.
Around 5% of the fatalities were in university graduates.
Race was also found to play a role, with around 9% of the black participants dying prematurely, compared to 6% of the white volunteers.
Black men were found to be significantly more likely to die by murder, while the white males were more at risk of succumbing to Aids.
Overall, most died from heart disease or cancer.
When the scientists looked at ethnicity and education together, the impact of race “all but disappeared”.
Of those who died with a high school degree or less, 13.5% were black and 13.2% white.
By contrast, 5.9% and 4.3% of the fatalities among college graduates were black and white, respectively.
Each “educational step” was found to result in “1.37 fewer years of lost life expectancy”.
The results remained true after the scientists adjusted for other factors that influence lifespan, like income.
“These findings are powerful,” said study author Dr Brita Roy.
“They suggest improving equity in access to and quality of education is something tangible that can help reverse this troubling trend in reduction of life expectancy among middle-aged adults.
“These deaths are occurring in working-age people, often with children, before the age of 60.”
Income aside, educated people have been shown to have greater self-esteem, social support and a “sense of control over life”.
These qualities may act as a “buffer” against stress, which can be dangerous.
Educated people may also be more aware of healthy behaviours, like eating well, exercising regularly and not smoking.
They may opt to live in “healthier areas”, with access to green spaces and few fast food chains.
The association can work both ways, with unhealthy children often struggling at school.
Research suggests those with asthma may find it difficult to concentrate.
Disabilities can also impact a student’s hearing, attention span and cognitive abilities.