New research suggests a low level of education may be as deadly as smoking.

Researchers at University of Colorado, New York University, and the University of North Carolina at Chapel Hill found a link between risk of death and education levels.

This is alarming because low levels of education are common. More than 10 percent of U.S. adults ages 25 to 34 do not have a high school degree, while more than a quarter have some college but no bachelor's degree.

 "In public health policy, we often focus on changing health behaviors such as diet, smoking, and drinking," researcher Virginia Chang said in a statement. "Education -- which is a more fundamental, upstream driver of health behaviors and disparities -- should also be a key element of U.S. health policy."

Previous studies show that a higher level of education is a strong predictor of longevity due to many factors, including higher income and social status, healthier behaviors, and improved social and psychological wellbeing. Evidence from studies including natural experiments consistently show a strong association between education level and mortality and suggest that a substantial part of the association between education and mortality is causal.

For the recent study, researchers collected and analyzed data on more than a million people from 1986 to 2006 to estimate the number of deaths that could be attributed to low levels of education.

They found that more than 145,000 deaths could be saved in the 2010 population if adults who had not completed high school went on to earn a GED or high school degree, which is comparable to the estimated number of deaths that could be averted if all current smokers had the mortality rates of former smokers. In addition, 110,068 deaths could be saved if adults who had some college went on to complete their bachelor's degree.

"Our results suggest that policies and interventions that improve educational attainment could substantially improve survival in the U.S. population, especially given widening educational disparities," said Patrick Krueger, assistant professor in the Department of Health & Behavioral Sciences at the University of Colorado Denver. "Unless these trends change, the mortality attributable to low education will continue to increase in the future."

Healthy People 2020 -- an initiative to improve Americans' health decade by decade -- set goals for increasing the proportion of students completing high school by 2020. The researchers said that based on their findings, meeting these goals could have a substantial impact on future survival patterns.

"Broadly, life expectancy is increasing, but those with more education are reaping most of the benefits," said Chang, associate professor of public health at NYU's Steinhardt School of Culture, Education, and Human Development and College of Global Public Health. "In addition to education policy's obvious relevance for improving learning and economic opportunities, its benefits to health should also be thought of as a key rationale. The bottom line is paying attention to education has the potential to substantively reduce mortality."

The findings are detailed in the journal PLOS One.