New Jersey, where life expectancy is 77.5 years, ranks 23rd- highest among the 50 states and Washington, D.C. Where people live, combined with race and income, are huge factors in why millions of the worst-off Americans have life expectancies typical of developing countries, Murray concluded. Asian-American women, for example, can expect to live 13 years longer than low-income black women in the rural South -- and 21 years longer than inner-city black men -- who have life expectancies similar to those in Third-World nations, the study found.

Health disparities are widely considered the result of minorities and the poor being unable to find or afford good medical care. Murray's county-by-county comparison of life expectancy shows that the reality is far more complex. Despite its long-lived Asian-American women residents, Bergen was not among the top 25 counties nationally for high life expectancy overall. This is because just 11.6 percent of Bergen County residents are Asian, while 82 percent are white and 6 percent are black, Murray said. The Asian-Americans in the study included immigrants and second-generation residents, he said.

Howard Shih, manager of census information at the Asian American Federation of New York, wondered whether wealth plays as much of a role in longevity as ethnic background. "I don't know if it's particularly being Asian or being well-off that's driving those numbers," he said. Each Asian subgroup seems to have a different explanation for its longevity. Raw tuna and green tea keep the Japanese alive, said Hiroyuki Gunji, a chef at Mitsuwa, a Japanese supermarket in Edgewater. East Indians depend on a diet heavy on vegetables and low on red meat , said Ravi Mehrotra, president of the Asian Indian Association of New Jersey. Prayer is the key for Filipinos, many of whom are Roman Catholic, said Nora Trivino, a member of the Filipino American Society of Teaneck. The Korean secret to long life is obvious, said Ji Yun Yoo of Fort Lee. "It has to be kimchi ," she quipped. Florence Chen, president of the New Jersey chapter of the Organization of Chinese Americans, even speculated that Bergen's diversity could help account for longevity. "Bergen County is very racially diverse," said Chen, who recently moved to Somerset County from Tenafly. "Maybe it's easier to be a minority, than, say, in Iowa." Murray analyzed census and mortality data from 1982 to 2001 by county, race, gender and income. He found some distinct groups that he called the "eight Americas": Asian-Americans, with an average per-capita income of $21,566, have a life expectancy of 84.9 years.

• Northland low-income rural whites, $17,758, 79 years.
• Middle America (mostly white), $24,640, 77.9 years.
• Low-income whites in Appalachia, Mississippi Valley, $16,390, 75 years
• Western American Indians, $10,029, 72.7 years.
• Black Middle America, $15,412, 72.9 years.
• Southern low-income rural blacks, $10,463, 71.2 years.
• High-risk urban blacks, $14,800, 71.1 years.

Disparities were most pronounced in young and middle-age adults. A 15-year-old urban black man was 3.8 times more likely to die before age 60 than an Asian-American, for example. Genetic inheritance does not appear to play a large role in these health disparities, Murray said. "The difference we observe in these groups is due to levels of chronic disease in young and middle-age adults, and almost all of that is due to tobacco, alcohol, obesity, cholesterol and diet," he said.

For now, the study has shown, "we have to put our energy into tackling the problem of chronic disease in young and middle-aged adults," he said. Murray's study is important, but not specific enough, said Diane Brown of the University of Medicine and Dentistry of New Jersey. The degree of neighborhood racial segregation and environmental exposure, such as industrial waste and pollution in a community, also influences longevity, said Brown, executive director of the Institute for the Elimination of Health Disparities at the UMDNJ School of Public Health in Newark. "I'm saying there are other factors that also need to be considered," she said. "It doesn't allow us to fully understand all the variation that occurs within the population of the counties." This article includes material from The Associated Press.