A new report confirms what we already knew: the rich live longer than the poor. The study looked at people in the United States who were in their fifties in 1991, and found that three-quarters of the richest among them are still alive today, compared to less than half of the poorest.

This isn’t really news, though it’s good to firm up the stats. Lots of other studies have concluded the same thing. A 2016 study found that the richest 1 percent of US women live more than a decade longer than the poorest 1 percent. And the gap is even wider for men. Bernie Sanders likes to share a statistic that life expectancy for men in West Virginia’s McDowell County, the poorest in the nation, is sixty-five years, while in Virginia’s Fairfax County, one of the richest, it’s eighty-two years.

The findings aren’t up for debate. The question that remains is: Why? How come the wealthy get to walk the earth longer than the poor? Unsurprisingly, some terrible ideas have been floated to explain the trend. In 2004, for example, some researchers claimed that rich people live longer because they are smarter and therefore have superior health literacy, which means they take care of their bodies better. In this view, the deficient poor are to blame for their struggles, both physical and economic. If only they were more intelligent, they would know how to make money, and also that smoking and fast food are bad for them.

To really explain why poor people don’t live as long as rich people, we need to look at the structure of capitalism, the thing that makes people rich and poor in the first place. Barring serious life-shortening disabilities and hereditary diseases, each human has the potential to live as long as every other human. But capitalism sorts humans into distinct classes. Most belong to the working class, which means they have to sell their labor to those who own companies in order to access the basic means of survival.

The owners of those companies are compelled, above all, to maximize profit. It’s not a matter of personal greed. It’s not even within their control. Maximizing profits is a mandate under capitalism. If corporations don’t ruthlessly pursue this aim, they’ll lose out to the competition and go under.

That profit motive drives the owners of corporations to do things like expand into new markets, privatizing the things people need and relentlessly jacking up their cost. It drives them to lobby the state for things like corporate deregulation, so they can pressure workers to improve productivity regardless of their safety and poison the environment regardless of health dangers to local communities. It drives corporations to lobby the state for tax breaks for themselves, money that inevitably comes out of social services for the same workers whose labor is lining their pockets. Finally, one thing that’s necessary for capitalists to maximize profits is suppressing the cost of labor itself, which requires, among other things, a permanent “reserve army” of the unemployed. That way bosses can say to any worker who asks for more money, “Hey, if you don’t like the terms and conditions of this job, someone else would be happy to take it.”

This entire arrangement places enormous stress on the working class. In countries that lack a robust welfare state like the United States, nobody is guaranteed a roof over their head, food on the table, or life-saving medical treatment unless they pay for it, and they can’t pay for it unless they work in exchange for wages. As a result, working-class people bust their asses to make ends meet. They work hard jobs that are bad for their health, exposed to toxic chemicals and performing repetitive motions that lead to injury. Oftentimes they work two or three of these jobs in order to pay for rent and keep the lights on. And even if they are lucky enough to cobble together the money to pay for the basic necessities like food and shelter, they can’t necessarily pay for emergencies, like the extra costs associated with cancer treatment.

Worst-case scenario, a person can’t find any job, and they end up living in their cars or out on the streets, without access to showers and steady meals, much less a healthy diet and exercise. Underemployed and seeing no path to a sustainable future, whole communities succumb to despair and witness a rise in depression, drug and alcohol addiction, violence, and suicide. These communities are often the hardest hit by pollution and by treatable diseases that nevertheless go untreated.

Poor people do not live shorter lives because they’re less smart than rich people. Decades of constant work in conditions that harm their health, and the anxiety and stress that attend financial insecurity, cut short their lives. “The stress of poverty is a death sentence,” said Bernie Sanders at a congressional hearing he convened in 2013. To eliminate the gap in life expectancy between the rich and the poor, we have to eliminate poverty itself.

We can go a long way toward eliminating poverty without eliminating capitalism. We can, for example, build up the welfare state so that people have guaranteed health insurance that isn’t tied to employment and is free at the point of service. We can invest public money in affordable and social housing so that housing costs cease to spiral and millions more can afford a roof over their head. We can regulate corporations and force them to pay their workers a living wage. But make no mistake: so long as capitalism exists, it will sort people into classes, and the capitalist class, driven to maximize profits, will seek to undo this social-democratic compromise. We can try to rein them in, but pulling against those reins is in their nature, and poverty is the direct result of their breaking free.

So we should strive for socialism. We should strive for a society where all work is performed to make society function best for the people who comprise it, not where work is allocated and structured to produce the highest possible profits for corporations, which inevitably means returning as little wealth as possible to the workers themselves. It’s not exactly around the corner, but we should strive for a society without classes at all. This would be a society where all people are truly equal, and where all have an equal chance of living into old age.