"We all sort of suspected there was quite a big number, but when we came down to the actual figure it was certainly revealing," said Aliya Jiwani, health policy researcher and lead author of the report, which was published by the journal BMC Health Services Research.

Jiwani said that while "the administrative costs have been an issue" in the health-care world for years, "the fixes that have been put in place have only aggravated the issue."

In fact, the paper notes that "administrative costs as a percentage of total care health care spending more than doubled from 1980 to 2010."

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The authors of the paper write that the savings from eliminating trillions of dollars in administrative waste over the years "could cover all of the uninsured" people currently in the U.S. if a single-payer system were adopted. They estimate the cost of covering all of the roughly 40 million Americans still lacking health insurance would be equal to just about half of the $375 billion in projected savings.

The balance of those savings, they write, could "upgrade coverage for the tens of millions who are under-insured."

While the paper identified a very big number of wasted dollars, it remains a big question of whether that could lead to a single-payer system anytime soon.

Congress has not seriously considered a single-payer system for the entire nation, such as one that could take the form of Medicare, the federally run program that covers Americans age 65 and over. Vermont recently scrapped its plan to move to the entire state to a single-payer system because the estimated costs were too high.

And the Affordable Care Act remains relatively unpopular in national opinion polls even as it offers federal subsidies, or tax credits, to help people sign up in private individual insurance plans sold on government-run exchanges.

Ed Haislmaier, a senior research fellow of health policy studies at the conservative Heritage Foundation, said "there's a whole lot of reasons" not to move to a single-payer model.

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Health insurance paperwork wastes $375 billion