That changes U.S. politics. Research has shown that the haves have different political positions from the have-nots. By living longer and healthier lives, the haves have more opportunity to influence the politicians who craft the policies and programs that distribute public goods and services.

Meanwhile, because low socioeconomic status leads people to be sicker and to die earlier, poor Americans have far less chance of shaping political life — or of pursuing the policies that would help improve their health and lengthen their lives, such as improvements in health care, education, child care, neighborhood safety, nutrition, working conditions and so forth.

Here’s how we did the research

To demonstrate how this insidious cycle between poverty, bad health, and early death works, we draw on our new study. For this analysis, we looked at data from the National Institute on Aging’s Midlife in the United States Study — a 1995 nationally representative survey that followed respondents until 2005, recording which of them died and survived during this 10-year period.

This data set includes a wide range of psychosocial, physical and mental health indicators, as well as various measures that registered how often individuals engaged in politics through volunteer work, attending social meetings and giving donations to political campaigns, among others.

We measured the gap in political participation between respondents who did or did not survive until 2005. What we discovered was that before respondents with poor health died, they were 56 percent less politically active than their peers who survived because of better health.

More broadly, we found that low socioeconomic status was directly linked to bad health, which in turn led to premature death. All of that reduced poor Americans’ ability to engage in political life.

To further test our theory, we also considered the possibility that the poor are generally less involved in politics — whether or not their health is good or bad, and whether or not they live a long time. This didn’t change what we found.

Why is this premature mortality so significant?

Millions of impoverished Americans die young

Political participation of the poor is overall lower because of poverty, bad health and many other factors, but millions of impoverished Americans across the country also die prematurely. For instance, in 2015, research funded by the National Institutes of Health and the Social Security Administration revealed that, since 1990, among the bottom quarter of Americans with the least education, life expectancy has either stagnated or decreased. That’s for well over 40 million people.

Add to this negative trend the fact that mortality among the poor increases during middle age — which is when citizens generally get more involved in politics. The premature disappearance of the poor, then, occurs precisely at the moment when they would be expected to reach their “participatory peak” in society. But they don’t live long enough to achieve that milestone.

If these health disparities among Americans were evened out to prevent the premature mortality of the poor, we could see a significant rise in overall participation in the U.S. For instance, turnout in presidential elections could increase from the current 55 percent to well over 70 percent.

There are political consequences to premature mortality among the poor

But as poor Americans die prematurely, they also erase from the statistics the adversities that cause their premature deaths in the first place. This masks the true level of social stratification and political disadvantage of vulnerable populations.

This selective elimination makes the U.S. electorate — those citizens who actually vote — more socioeconomically homogeneous over time. Today, wealthier Americans are therefore overrepresented in the middle to older age brackets of society, where many poor people never manage to get into because of their shorter life spans.

Inequality in the U.S., in other words, is not solely the result of economic difference. Health, too, has considerable potential to stack the deck against the poor. Socioeconomics, longevity and political participation mutually reinforce each other, making it especially difficult for poor Americans to gain political clout.

All of that is worse in the U.S. than in other developed nations

Such disparities aren’t as extreme in other developed countries. The U.S. has the highest rates of poverty and wealth inequality among the world’s wealthiest countries, such as Germany, Japan and the United Kingdom. At the same time, it has lower rates of economic mobility than Spain.

In terms of health, the U.S. has the highest infant mortality rate among developed countries as well as the lowest life expectancy overall. While the citizens of other wealthy nations live longer every year, in the U.S., longevity has declined for the second consecutive year — with early mortality concentrated among the poor.

In the U.S., those social groups that might pressure for policies to alleviate these disparities are precisely those who die at higher rates than their wealthier peer groups. As a result, political participation in the U.S. is more skewed toward the rich than in countries with lower inequality (such as Australia, Canada, Germany, the Scandinavian nations or Japan), where fewer people die prematurely because their governments provide better health care for the poor.

Javier Rodríguez is assistant professor in the department of politics and co-director of the Claremont Inequality and Policy Research Institute at Claremont Graduate University.