As the GOP inches closer to repealing and replacing Obamacare, there’s no shortage of claims flying around about the impact giving people health insurance — or taking it away — has on American lives.

Researcher, policy wonk, and New Yorker writer Atul Gawande had heard them all: Medicaid doesn’t work, driving down coverage rates will result in more deaths, insurance coverage doesn’t actually improve health or mortality, and on and on.

So he wanted to comb through the research himself to see what studies on the health effects of health insurance show. Together with resarchers Benjamin Sommers and Katherine Baicker — who are two of the leading experts on this subject — Gawande just put out a review of that literature. Their analysis was published Wednesday in the New England Journal of Medicine, on the eve of the long-awaited release of the Senate health reform bill, the Better Care Reconciliation Act.

The trio’s conclusions are pretty unequivocal.

“The bottom line,” Gawande told Vox, “is that if you’re passing a bill that cuts $1.2 trillion in taxes that have paid for health care coverage, there’s almost no way that does not end up terminating insurance for large numbers of people.”

He continued: “If you are doing that, then there’s clear evidence that you will be harming people. You will be hurting their access to care. You will be harming their health — their physical health and mental health. There will be deaths.

“As a doctor, I find this unconscionable.”

For every 300 to 800 people who get insurance, about one life is saved per year, they found. The cost to society is somewhere between $300,000 and $800,000 per life saved. “Other policies that save lives — for example, health worker safety protections and environmental regulations — cost closer to $7.6 million per life saved,” he said. That means health insurance is a pretty good deal.

It also means the debate about the repeal and replacement of Obamacare, and whatever health law, if any, comes next, is really a debate about what we value as a society and whether we consider these costs worthwhile.

For a summary of their findings, check out Gawande’s tweetstorm yesterday:

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