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On June 9, the White House announced that a program that lessens the burden of student loan repayment will be extended to another 5 million people, who will soon be able to limit their monthly payments to no more than 10% of their monthly income.

That will certainly lessen the financial and psychological pressure on people struggling to repay those loans, but it may affect people's health in other unexpected ways too. 

We've known for a long time that debt is associated with mental health problems like depression and with higher suicide rates, but a few recent studies show that people with a lot of debt are also more likely to suffer from high blood pressure and other general health problems. And while poor mental health tends to contributes to poorer physical health, researchers say that they didn't expect to see such strong effects on physical health in young people.

How Personal Debt Is Harmful

The national student loan debt load is now approximately $1.2 trillion, having more-than tripled since 2004. It's bigger than either credit card or auto loan debt, and is the only type of consumer debt that has grown since consumer debt peaked in 2008.

That growing burden has prompted some researchers to investigate the complicated relationship between debt and health.

"There had been a fairly strong and consistent link between debt and depression, debt and thoughts of suicide," said Elizabeth Sweet, the lead author of one study out of Northwestern University, told Time Magazine. "But very little had been done to look at the impact on physical health."

Sweet's team analyzed a study that followed a group of young adults over a 15 year period. They were able to use data that included information about both personal debt and health for 8,400 people.

They found that household debt was a significant predictor of health. They focused on all personal debt except home mortgages, including student loans, credit cards, auto loans, and medical or legal bills (student loans make up the greatest proportion of these types of debt, especially for young people).

Since this group had been enrolled in the study for a number of years already, researchers were able to control for pre-existing health conditions. They also controlled for demographic factors like race, income, and pre-existing psychiatric conditions.

People who owed more had higher levels of stress and depression and worse overall health, particularly if they owed more than they owned (a home was not included on the assets side, just as a mortgage was not included on the debt side). People who subjectively judged that their debts exceeded the value of their assets were also more likely to have higher blood pressure. This effect was small but significant, as even a small rise in blood pressure can strongly increase the risk of stroke and hypertension.

The impact of mental health on physical health is important here. Many of these physical problems can be triggered by chronic stress, depression, and anxiety. It also seems plausible that people who are stressed about bills are likelier to forego medical care, an alternate explanation for the correlation between ill health and too much debt.

Seeking Solutions

Other  recent studies  have found similar connections between debt and poor health.

Being sick is expensive, and since personal debt is associated with poorer health in young people, that could have long-lasting effects for the rest of their lives. That's one reason why finding ways to deal with the rapid rise in student loan debt is important.

Still, researchers say there are relationships between debt and health that still need to be investigated, and, of course, debt isn't all bad. Debt is positively associated with income, the researchers note, possibly because people need to go into debt for school or to make investments.

But the researchers say that they were particularly surprised by the strong negative health effects they observed.

"You wouldn't necessarily expect to see associations between debt and physical health in people who are so young," Sweet said in a statement. "Since the 1980s American household debt has tripled. It's important to understand the health consequences associated with debt."