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Don't use drugs, stay in school — kids hear this kind of advice all the time. What they don't hear is that not having a good education could be just as dangerous to their health as smoking.

That's the takeaway of a new study, published Wednesday in the journal PLOS ONE. The authors of the study calculated the health risks of low educational attainment in the U.S. and found that more than 145,000 deaths could have been prevented in 2010 if adults who did not finish high school had earned a GED or high school diploma — comparable to the mortality rates of smoking.

In addition, another 110,000 deaths in 2010 could have been saved if people who had some college went on to complete their degree.

[What does your education say about your health?]

The death counts are an estimate of education's impact on mortality, and do not indicate  direct causality.

These figures are based on health risk associated with low education, which is a figure calculated through existing data on mortality rates for different levels of educational attainment. The data is adjusted to different populations and then multiplied by the population to get a number of deaths.

There are factors, such as childhood health or genetic predispositions, that are not accounted for to inflate the counts. Still, it's the same method used to calculate deaths associated with smoking and diet behaviors, so the numbers are comparable.

"As a scientist, the onus is on the researchers to demonstrate causality," said Patrick Krueger, an author of the study and a professor at the University of Colorado Denver. "Our paper doesn't look at causality directly, but we rest on previous studies."

There have been scores of papers published, the study says, establishing that poor education can lead to riskier behaviors, inadequate health care, poor nutrition and poor housing and working conditions. That leads to increased stress levels, affecting things like the immune system and cardiovascular health.

It's a complicated causal link, but Krueger says the evidence is strong enough to say there is a strong inverse relationship between educational attainment and adult mortality. In general, that means a better education translates to higher quality of life.

[How well-educated is your home county?]

There's been an increased interest over the past decade in academic communities to see how social factors contribute to the diseases that affect death rates. The push is in part to examine what's causing deaths beyond direct medical problems. Originally it started with more obvious behavior factors, like food and drug consumption, but it's expanded over time to include things such as segregation, poverty and income inequality.

"It's hard to get an individual to quit smoking, but it's easier to do on a population level," Krueger said.

Broader impact estimates, he suggested, are easier to spur policy changes, such as taxing products linked to harm. In terms of education, he said, that could mean putting a greater emphasis on expanding high school degrees, which he said is the strongest piece of data in the study.

"It's pretty reasonable for everyone to get a high school degree," he said. "It wouldn't be reasonable for everyone to get a doctorate degree."

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