At the other extreme are Native Americans in South Dakota, whose average life expectancy is 58 years. "That's comparable to the life expectancy in Southeast Asia and in sub-Saharan Africa," said Richard M. Suzman, associate director of the National Institute on Aging, which partially funded the study.
The difference is not directly related to income, insurance, infant mortality, AIDS or violence. Rather, the contributing factors, in order of importance, are tobacco, alcohol, obesity, high blood pressure, high cholesterol, diet and physical inactivity, said Dr. Christopher J. L. Murray of the Harvard School of Public Health, who led the study.
"Those seven are likely to explain a lot of the patterns that we see," he said. "They also give us some hints about the types of public health and medical care interventions that could make a difference in these disparities."
The life-span disparities are so severe that the researchers concluded that there are "eight Americas," each with its own racial, geographic, income, and life expectancy. The report did not separate out Latinos.
"There are millions of Americans that have life spans the same as in developing countries," Murray said. "That alone is pretty remarkable, considering we spend $5,000 a year per person on healthcare."
The data show that the gaps between groups have not been closing over the last two decades. If anything, they are increasing, Murray said, despite a series of policy initiatives.
"In simple terms, there has been a lot of discussion and effort, but no progress," he said.
Briefly, the eight Americas are defined as:
* 10.4 million Asians, average per capita income $21,566, in 1,889 counties, life expectancy 84.9 years.
* 3.6 million low-income whites in 112 rural counties in the Northern Plains and Dakotas, average income $17,758, life expectancy 79 years.
* 214 million middle-income Americans scattered through the country, average income $24,640, life expectancy 77.9 years.
* 16.6 million low-income whites in 467 rural counties in Appalachia and the Mississippi Valley, average income $16,390, life expectancy 75 years.
* 1 million western Native Americans in 359 counties, average income $10,029, life expectancy 72.7 years.
* 23.4 million middle-income black Americans in 1,632 counties, average income $15,412, life expectancy 72.9 years.
* 5.8 million southern low-income blacks in 427 rural counties, average income $10,463, life expectancy 71.2 years.
* 7.5 million high-risk urban blacks in 13 urban counties with the highest homicide rates, average income $14,800, life expectancy 71.1 years.
When the data is broken down by counties, the lowest life expectancy, 66.6 years, is found in Bennett, Jackson, Mellette, Shannon, Todd and Washabaugh counties in South Dakota -- all areas with large, reservation-based Native American populations.
The counties with the longest life span, 81.3 years, are Clear Creek, Eagle, Gilpin, Grand, Jackson, Park and Summit counties in Colorado, Montgomery County, Md., and Lyon and Sioux counties in Iowa.
The gap has been growing since 1984, Murray said. "The counties that started the best just keep getting better. Those at the bottom either stayed the same or got worse."
According to the state data, Hawaii is the healthiest, with a combined life span for men and women of 80 years.
The District of Columbia is the worst, with a life expectancy of 72 years.
It is followed by Mississippi, 73.6 years, Louisiana, 74.2 years, Alabama, 74.4 years, and South Carolina, 74.8 years.
California ranks 10th with a combined male and female life expectancy exceeding 78.2 years.
Personal choices may be more important than access to medical care, Murray added.
Although 85% of the population has health insurance, half of those with high blood pressure fail to get it controlled, he said. Two-thirds of those with high cholesterol do not receive statins to bring it down and two-thirds of those with diabetes fail to get it managed, he added.