ENERGETIC: Sadiq Sawut, 121-year-old, from Xinjiang Uygur Autonomous Region (CFP)

There is no rest home in Bama. It is common to see five generations of one family living together harmoniously. All people there live peaceful lives without any tension. The only "competition" is the traditional folk song contest. All people, regardless of age, participate in the contest. It is the best entertainment for local people and is considered a good way to keep young, physically and mentally.

Natural conditions in Bama also contribute to the longevity of local people. Scientists found the content of manganese and zinc is extremely high in the soil of the northern mountain area, while that of copper and cadmium is low. Researchers said soil with a high content of manganese and a low content of copper can reduce the rate of cardiovascular diseases, while zinc can improve immunity.

Fresh air is considered to be another helpful factor. Most long-lived people in Bama live in the valley or by the riverside, where there is no pollution at all. Researchers said the content of negative oxygen ions per cubic centimeter of air in Bama reaches 2,000 to 5,000, and the number is as high as 30,000 in some villages known for their long-lived inhabitants. In other areas, the content of negative oxygen ions is usually between 1,000 and 2,000. In addition, people in Bama are less exposed to solar radiation, which is good for health.

From the story of Bama, many people would think longevity only exists in remote mountain areas or less developed regions. But in Guangdong Province, one of the most affluent regions in China, the number of long-lived people has also been increasing.

In Sanshui, a township in Foshan city, 30 km from Guangzhou, capital of Guangdong Province, high energy consumption and high pollution industries have been relocated or closed since the 1990s. At the same time, the number of centenarians there has increased markedly.

"Sanshui has struck a balance between economic development and environmental protection," said Zhao Baohua, Vice President of GSC.

Apart from this, experts say the soil, water and food in the Sanshui area are rich in selenium, a microelement that can effectively prevent cardiovascular diseases, arteriosclerosis and other diseases. Selenium deficiency may result in reduced immunity.

Research has shown lifestyle accounts for 60 percent of factors contributing to one's health and longevity. A healthy lifestyle could prolong one's life by at least 10 years. It also reduces one's chance of high blood pressure by 55 percent, chance of stroke by 75 percent, chance of diabetes by 50 percent and chance of cancer by nearly one third.

The World Health Organization has issued guidelines for a healthy lifestyle: regular diet, appropriate exercise, no smoking and limited drinking, and a balanced mind. The guidelines are in line with the traditional Chinese medical theories on maintaining health, said Hu Xiaofei, a professor at the Beijing Sport University who has studied traditional Chinese methods of health preservation for more than 20 years.

In Hu's latest book, he introduces traditional health preservation theories and methods, based on the regimen of Emperor Qianlong of the Qing Dynasty who died at 89 years old. Hu also created a set of exercise movements that can help to improve health and prolong one's life through three basic measures: mental activity, breathing and physical exercise.