Overweight and obese people might be able to start losing weight by consuming beneficial bacteria after a discovery by scientists at a top medical institution in Shanghai, who aim to use the findings to develop a new weight-loss drug.

Bacteroides thetaiotaomicron, or BT, a bacteria that resides in and dominates the human intestinal tract, was found to be able to lower fat content in the diet and slow down weight gain, according to researchers from the Shanghai National Clinical Research Center for Endocrine and Metabolic Diseases at Shanghai Ruijin Hospital.

The discovery, published online by the scientific journal Nature Medicine, has opened the door for further studies on the bacteria's employment in food and drugs that are expected to help lose weight, though more research still needs to be done to test its safety and efficiency.

"In the past, genetic and environmental factors have been cited as the main causes of obesity," said Ning Guang, chairman of the center and an academician at the Chinese Academy of Engineering.

"But the microbes living in the intestinal tract are the first to 'taste' food and serve as the leading cause of weight gain," he said.

The findings have been released at a time when the number of obese people in China - already the largest number worldwide - continues to rise and poses an increased health risk given the improved living standards and prevalence of modern sedentary lifestyles.

Worldwide, more than 2 billion people, or one-third of the global population, are now overweight or obese, according to a new study by The New England Journal of Medicine.

The study found that obesity numbers have tripled in children and young adults in countries like China, Brazil and Indonesia. Those numbers are particularly troubling because it means more young people are on track to become obese and develop health problems.

But the scientists at Ruijin Hospital discovered that BT has the capability to metabolize glutamate, the main ingredient in MSG - the intake of which could contribute to the high levels of overweight adults.

However, experts warned that the diet and genetic background of Chinese people are different to those of Westerners, and so are the microbes in their intestinal tract.

Therefore, the study results are more relevant to helping develop a new weight-loss drug for Chinese people, rather than their Western counterparts.