Every year, a new paper argues, tens of thousands of Americans die sooner than they should for an entirely preventable reason. It's not smoking, or not exercising, or eating sugar. It's dropping out of high school and college.
In 2010 alone, more than 145,000 deaths in the US could have been prevented if high school dropouts had finished their secondary education, three public health researchers argued in a recent paper. Getting college dropouts to graduate could have saved 110,000 more.
If everyone in the US had a bachelor's degree, they estimated, it could prevent half a million premature deaths each year.
In general, people with more years of education tend to be healthier. This could be because the knowledge they gain actually helps them — by making them more likely to exercise and eat well, or by making it easier for them to follow doctors' directions. Or it could be because having more education brings other social benefits.
The researchers framed the issue, with specific numbers of deaths they say were preventable, to emphasize that education is a public health issue. They want to make it clear that not being educated, just like choosing to smoke, can be deadly.
Healthier people are more educated. But it's not entirely clear why.
It's conventional wisdom that people with more education are also healthier. But it's surprisingly difficult to untangle why that's the case, because it's not clear whether it's the education or the degree itself that makes the difference.
People might be healthier because getting more education makes them better able to take care of themselves or not get sick in the first place. A 2001 study found that patients with more education were better at complying with treatment for conditions like diabetes and AIDS, for example. More educated people are also less likely to smoke, more likely to exercise, and less likely to be obese — all of which make people less likely to get sick in the first place.
But people with more education also earn more money and have a higher socioeconomic status. They've historically been more likely to have health insurance, less likely to be unemployed, and less likely to live in poverty.
Researchers who've studied the connection between education and health say those other factors can't entirely explain the health disparities between more- and less-educated people. But they admit that it's very difficult to tell whether it's the education itself that makes the difference.
Some research suggests it's the degree, not the education itself, that matters the most. This is called the "sheepskin effect" — that whatever benefits education alone might bring (such as the ability to better follow directions and thus follow a diabetes medication regimen, for example), they're not as great as the benefits from obtaining a degree.
An analysis of the Framingham Heart Study, which has followed the residents of a Massachusetts town since 1948 to track their health, found that how many years people had been to school didn't have an effect on their risk of heart disease. But whether they had a degree did.
The difference matters. If it's the degree alone that's important, we could substantially improve Americans' health by enrolling everyone in a diploma mill, or making it much easier to graduate from college. Since there's also a gap in health outcomes between high school degree recipients and dropouts, that suggests that raising the high school graduation rate from 80 percent to 90 percent or 100 percent really could make a difference.
But the degree might also be important because of the social status it brings. In that case, getting everyone to graduate might not make any difference at all, because degrees are a status hierarchy.
Economic and social benefits accrue partly because people with more education are relatively rare. Only about one-third of the US has a four-year college degree. In other words, leave aside that it's very unlikely that every American would ever get a college degree — even if they did, it might not save their lives.
The best option, the research suggests, might be to make the lives of people with less education look more like the lives of the educated, whether or not they finish their degrees.
How the researchers came up with their numbers
The paper, published in the scientific journal PLOS One, argues that finishing high school has the same health benefit as quitting smoking — or, to put it another way, that dropping out of high school has the same long-term effect on your health as becoming a smoker.
Using data from the National Health Interview Survey, which asks more than 1 million Americans about their health each year, they calculated mortality rate for Americans born in 1925, 1935, and 1945, broken down by sex and the level of education those people completed. Then they calculated how many fewer deaths there would have been if less-educated people died at the same rate as more-educated people.
They argue that a better-educated population could save a lot of lives, particularly from heart disease, which causes about 25 percent of the deaths in the US each year. Education appeared to be a much bigger factor in deaths from heart disease than from cancer, particularly among women: Researchers calculated that 16 percent of heart disease deaths among women born in 1945 who dropped out of high school were attributable to their lower level of education. (Cancer deaths were much less affected by education levels.)
Perhaps the researchers' most worrying finding was that the gap between less-educated Americans and their better-educated peers was widening across generations. Among people born in 1945, lack of education appeared to be a much bigger factor in dying young than it was among people born 20 years earlier.
If that's true, then attempts to get more Americans to graduate from high school and particularly college aren't just economic policies. They're often framed that way, because the US is falling behind other advanced countries in college graduation rates. But the researchers argue that getting more people to finish high school could also be considered a lifesaving intervention.