What makes Bama's residents live longer?

Bama Yao autonomous county in Guangxi Zhuang autonomous region was established in 1956. The local authority conducted a population census and was stunned by the result: Of a population of 130,000, there were 15 people aged more than 100 and dozens aged above 80.

At that time, the life expectancy in China was only 45, according to World Population Prospects, the 2008 Revision, released by the United Nations.

This record of longevity has been sustained. Experts from the Ministry of Health are drawn to the spot, seeking the secret of long life, says Chen Jinchao, the director of Guangxi Bama Longevity Research Institute.

"Although there isn't a single overriding factor to explain the longevity of Bama's residents, it is widely accepted that the natural environment and lifestyle here play important roles," Chen says.

The most remarkable thing is that villagers here have a tradition of healthy lifestyle.

In the past, due to poor transportation facilities, salt and meat were hard to get in these remote villages, located deep in the mountains. Cooking oil was mostly extracted from plant sources.

As a result, their regular diet was low-fat, low-salt, and included items that were boiled rather than fried. The habit hasn't changed much since.

Meanwhile, because of the bad infrastructure, such as absence of electricity and transport, alcohol and cigarettes were in short supply and entertainment sources were limited. Going to bed early and getting up early was the logical choice, which is still pretty much the practice.

Besides, the elderly are well respected in the county. Bad behavior toward the elderly tends to draw a lot of flak, and such offenders are generally shunned, Chen notes. "The natural environment, the climate and geology here have shaped the lifestyle practices followed here," Chen says.

The county is located between plateau and marine climates, fostering a healthy growth of vegetation. It rains throughout the year, except in winter.

As a result, the oxygen in the air is much higher than the average level in China, and the humidity is neither too much nor too little. "We don't need to use skincare products, since the air is clean, fresh and moist all the time," Chen says.

The water and the earth are rich in micronutrients that are important to build a strong body, such as zinc, strontium, and magnesium. Hazardous minerals are scant and there is no industrial pollution.

Vegetables boiled in local water taste sweet, because the earth is so rich in micronutrients, Chen says.

"Achieving longevity is a very complicated issue," says Zhang Tiemei, vice director of the Beijing Institute of Geriatric Medicines with Beijing Hospital.

"A balanced lifestyle is the most important and easiest way, but lifestyle is influenced by many factors, such as career, living environment and education.

"Longevity should be the result of healthy aging, rather than trying to achieve longevity for its own sake."

As more and more elderly rush to Bama, Zhang sounds a note of caution.

On one hand, living in a remote, somewhat strange place would mean being cut off from one's friends and family. It would take some adjusting to the new environment both physically and mentally.

On the other hand, the elderly are quite vulnerable, especially physically, and even a cold may develop into life-threatening pneumonia.

"Migration is a personal choice, but may not always be a wise one for someone who is old," Zhang says.