Murray's team looked at the biggest national health surveys, with data on millions of Americans. They broke it down county by county—and then compared the numbers to other big surveys in other countries.
"In the highest-performing counties, life expectancy rivaled countries with the highest life expectancy in the world, such as Switzerland and Japan," they wrote.
"In the lowest-performing counties, life expectancy was lower than the life expectancy of countries receiving foreign aid such as Algeria and Bangladesh. The lowest life expectancies in the U.S. remained around 73 years for females and below 65 for males between 1985 and 2010."
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"There are places with the best life expectancy in the world in the U.S., and there are places in Mississippi, for example, or West Virginia where life expectancies are in the mid-60s for men and low 70s for women. That's about the same as a number of poor developing countries," Murray says.
"The United States spends more than the rest of the world on health care and leads the world in the quality and quantity of its health research, but that doesn't add up to better health outcomes," Murray said in a statement.
One place the U.S. does better—treating some cancers.
"Five-year survival for breast cancer and colorectal cancer are higher in the U.S. than in many OECD countries," they wrote.
The biggest killers: clogged arteries (known medically as ischemic heart disease), lung cancer, stroke, chronic obstructive pulmonary disease and road accidents.
But the diseases that caused the most misery, known in the lingo as disability-adjusted life years, are low back pain, major depressive disorder, other musculoskeletal disorders, neck pain, and anxiety disorders.
In fact, Americans are more disabled now than they were 10 years ago, the researchers found.
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"The gap between life expectancy and healthy life expectancy, a measure of the expected number of healthy years that an individual loses to disability—increased from 9.4 to 10.1 years. In other words, individuals in the U.S. are living longer, but not necessarily in good health," they concluded.
"The United States spends the most per capita on health care across all countries, lacks universal health coverage, and lags behind other high-income countries for life expectancy and many other health outcome measures. High costs with mediocre population health outcomes at the national level are compounded by marked disparities across communities, socio-economic groups, and race and ethnicity groups."
One underlying cause is poor diet. "The most important dietary risks in the U.S. are a diet low in fruits, low in nuts and seeds, high in sodium, high in processed meats, low in vegetables and high in transfats," they wrote.
"Unhealthy diets and a lack of physical activity in the U.S. cause more health loss than smoking, alcohol, or drug use," said Dr. Ali Mokdad, who worked on the reports.
But Dr. Steven Woolf of Virginia Commonwealth University, who chaired a National Academy of Sciences panel that reported on U.S. health in January, says it's more complex than just bad habits.
"It's unsophisticated to say it's because we are not eating right," Woolf said in a telephone interview.
"There is a large contingent of Americans who react by saying this is a matter of personal responsibility. To some extent that's true but there is much more about the way our lives are structured in the U.S."
Counties that score higher in terms of health have social services that support parents and better education outcomes, Woolf argues.
How does your county rate? Check the U.S. health map
And Jeff Levi of the Trust for America's Health sees a telling pattern in the county-by-county breakdown of U.S. health.
"Those distinctions are really about income and education level," Levi told NBC News.
"OECD countries are spending more on education and income support than we do and that is what is helping to create this healthier environment," he added. "We need to really try to get at the social and environmental causes of these issues and really focus on true prevention, which is not managing in a clinical setting but creating the conditions where this doesn't happen in the first place."
Woolf says a lot has to do with public perception. "We are much more afraid of plane crashes and being struck by lightning and not afraid of the things that are far more likely to claim our lives," he said.
"The other reflex people have is to say social programs are important but we just can't afford it. We have plenty of money for it," he added.
"If you look at how much money the United States spends on heath, our budget for health exceeds that of every other country in the world."
—By Maggie Fox, NBC.