A new analysis of life expectancy around the world and within the US finds Americans are lagging behind other industrialized countries, and also identifies vast disparities within the United States.

Life expectancy for American men was about 75.5 years in 2007, the most recent year reported. That put the US in 37th place, behind Australia, Japan, Canada and many European countries. American women fare better, with a life expectancy of almost 81 years. But the global ranking has steadily fallen over two decades, putting US female life expectancy also in 37th place among almost 200 countries and territories.

Ali Mokdad is a professor at the Institute for Health Metrics and Evaluation of the University of Washington, which compiled the life expectancy data. He says increases in life expectancy have lagged in the United States compared with other countries.

"We've seen an improvement almost everywhere in the world, and in countries that are developed, we're seeing a higher improvement, a faster improvement rate, than we are seeing in the United States."

Mokdad says the reason is that America has made less progress in reducing risk factors that can shorten life, such as obesity and high blood pressure.

The report highlights substantial disparities within the United States, too.

Color-coded maps show life expectancy in each of the nation's 3,000-plus counties. Red and orange signify the shortest projected life span and those colors cluster together in the South.

That's the region where lower socioeconomic status and high rates of health risk factors; plus more limited access to quality medical care all contribute to shorter lifespans.

"Less education, less income in some of these rural counties, more likely to be smokers, more likely to be obese," Mokdad says. "They don't have health insurance or they don't have adequate access to health care, and the quality of medical care is not as good as well."

In the United States, many public health responsibilities are local, not national. Some communities restrict smoking in the workplace. Some have bicycle paths. Some organize farmers markets.

"So programs like this are efficient. They work. They change the environment. And this is a long-term investment, like you build a school, you're going to see the impact of that school 20 years down the road. The same for public health: a long-term investment in their community to increase physical activity and improve diet are needed in this country."

Dr. Ali Mokdad of the University of Washington, Institute for Health Metrics and Evaluation, is discussing a new study of the institute on life expectancy published in the journal Population Health Metrics.

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（來(lái)源：VOA 編輯：崔旭燕）