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Underweight Asians Face Higher Risk of Death

A new study of more than 1.1 million people in six Asian countries finds that, like Westerners, Asians are more likely to die if they are overweight or obese. However, some of the highest death rates were seen in people who were severely underweight.

Many previous studies have found that the risk of death increases as body-mass index increases. Body-mass index, or BMI, is a measure of body fat based on height and weight. The trouble is, those studies mostly analyzed Europeans and other Westerners. So scientists couldn't be sure if the results applied to other groups.

To find out, Wei Zheng of Vanderbilt University and his colleagues collected data from China, Taiwan, South Korea, Japan, Bangladesh, and India. Adding up all the numbers, they concluded that the relationship between BMI and death rate in these Asian populations is generally consistent with studies of Westerners.

"Those people with lowest mortality in East Asian countries are those with normal weight," Zheng said. "And then with the reduced BMI and also increased BMI, they have increased risk of death."

That part about those with "reduced BMI" is important because proportionately, more people in Asia are at the lower end of the BMI scale.

"For example, those with BMI less than 15, so this study shows really those with very low BMI have very high risk of death. This is a clear message for those people, [they] need to gain weight."

The study also highlighted a surprising difference between East Asians and South Asians. Among the Indians and Bangladeshis, a higher BMI - in the overweight and obese range - did not translate into a notably higher death rate. Zheng says it might be that their weight reflected prosperity and a higher position in their community.

"They had relatively high socioeconomic status, so they had better access to health care," he suggested.

Long History, Unclear Future for 'Golden Rice'

This is the VOA Special English Agriculture Report.

White rice is the world's most popular form of rice. But it goes through a milling process that removes many nutrients. As a result, people who eat a poor diet based on white rice may not get enough vitamin A.

Each year an estimated two hundred fifty thousand to half a million children go blind from vitamin A deficiency. The World Health Organization says half of them die within a year of losing their sight. Vitamin A deficiency is a problem especially in Africa and Southeast Asia.

So scientists thought of an answer. They combined white rice with plant compounds that the body can change into vitamin A. The rice contains beta-carotene and other carotenoids. These plant colorings give the rice a golden color.

The scientists also thought of a plan to give away this Golden Rice for free to poor farmers. But the rice is genetically engineered. They say it cannot be made using traditional methods to breed plants.

The scientists worked for ten years, until nineteen ninety, to develop the technology to add genes to rice. Then it took nine more years to get the genes they wanted into the seed.

The first field tests took place in two thousand four at Louisiana State University in the United States. Golden Rice is currently being tested in the Philippines. It is still not available for general use.

Co-inventor Ingo Potrykus says rice with two added genes will be available in twenty-thirteen. One gene comes from maize, or corn, and the other from a soil bacterium.

Mr. Potrykus is retired from the Swiss Federal Institute of Technology. He blames the delays on too many rules about genetically modified crops.

Opponents say such crops may cause environmental damage by breeding with conventional plants. Opponents also question the safety of biotech foods.

Mr. Potrykus says Golden Rice has never been shown to be unsafe for the environment or people. Many agricultural organizations support the project.

But there are also critics, including researchers for the environmental group Greenpeace. Several months ago they questioned whether Golden Rice could do much for vitamin A deficiency. They said releasing genetically modified rice in Asia could permanently change traditional rice varieties and wild ancestors of rice.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. For more news about rice research, go to . I'm Bob Doughty.

States Put Pressure on Public Unions

This is the VOA Special English Economics Report.

Americans have been watching the protests in the Middle East and North Africa -- and closer to home. Workers in Wisconsin, and now some other states, have been protesting efforts to limit the negotiating power of government employees.