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The cause of obesity was found to be bacteria
Medical expert of the article
Last reviewed: 01.07.2025
Obesity is one of the most common problems in developed countries, excess weight provokes the development of many diseases and increases the risk of premature death. The reasons for gaining extra pounds are, naturally, a sedentary lifestyle, poor nutrition and overeating, as well as genetic predisposition.
But in recent years, it has become increasingly clear to scientists that enterobacteria, a special class of bacteria that live in the gastrointestinal tract, play an important role in the biology of humans and animals.
Scientists from Shanghai Jiaotong University have concluded that a bacterial infection may be to blame for obesity. The results of the specialists' research were published in the scientific journal "International Society for Microbial Ecology".
Experts have been studying the link between excess weight and stomach infection for eight years. The important role of enterobacteria in obesity was first established after clusters of this class of bacteria were found in volunteers in large quantities, experts report.
To confirm or disprove their hypothesis, Chinese scientists decided to conduct an experiment on mice.
The rodents were fed fatty food and their mobility was limited. One group of animals was infected with enterobacter bacteria. It turned out that only those rodents that were infected gained excess weight - they quickly began to gain kilograms. Those mice that were "clean", despite the slaughter feeding and sedentary lifestyle, did not gain weight.
Mice were injected with bacteria for ten weeks.
"Our experiments provide clear evidence that obesity may not be the result of a sedentary lifestyle, overeating or unhealthy eating habits, but a bacterial infection," says Zhao Lipina, lead author of the study and a professor at Shanghai Jiaotong University. "Enterobacteria inhibit the process of fat breakdown and imbalance the secretion of genes responsible for controlling metabolism, thus pushing the body to produce fat and accumulate it."
Enterobacter bacteria are part of the flora in the human intestine, but can play a negative role, provoking the process of obesity. Also, in the course of research, specialists discovered that enterobacteria secrete substances that provoke the body's insensitivity to insulin.
According to Professor Zhao, he has already cured at least one obese patient. The doctor says that the overweight man lost weight over 23 weeks and as a result was able to lose 29% of his body weight. But in addition to losing weight, Dr. Zhao's patient was able to get rid of diseases: he recovered from fatty liver infiltration and hypertension. The professor says that he was able to achieve such amazing results with the help of a diet that was aimed at suppressing the activity of enterobacteria. And the patient's diet consisted of traditional Chinese medicines, whole grains and prebiotics - indigestible carbohydrates.