Bacteria Could Cause Obesity!

A number of things could lead to overweight or even obesity, for instance, high fat diet, lack of physical activities, genes, or lack of sleep. Researchers in Shanghai, China recently reported that obesity could be caused by bacterial infection.

In a paper published on 13 December 2012 by ‘Journal of the International Society for Microbial Ecology’, researchers from Shanghai Jiao Tong University found that mice bred to be resistant to obesity even when fed high-fat foods became excessively overweight when injected with a kind of human bacterium and fed with a rich diet.

After following an 8-year search by scientists around the world to explain the association between gut bacteria and obesity, the Chinese researchers identified a human bacterium that caused obesity. The bacterium, which is also known as enterobacer, encourages the body to make and store fat, and prevents it from being used by deregulating the body’s metabolism-controlling genes.

Enterobacter also release chemicals, called endotoxins, which cause insulin resistance and a slower uptake of glucose from the blood after eating. Patients tend to eat more since they take longer to feel full.

As part of the experiment, mice were injected with the bacterium that was found in high quantities in the gut of a morbidly obese human volunteer for up to 10 weeks. Their weight gain was compared with mice without feeding with the bacterium. The latter did not become obese despite being fed with a high-fat diet and being prevented from exercising. Results of the experiment showed that the bacterium might causatively contribute to the development of obesity in humans.

The study also found that the human volunteer, who was prevented from doing any exercise, lost 29 percent of his body weight in 23 weeks after being placed on a special diet that cut the bacterium's presence in his gut to undetectable levels. The volunteer also recovered from diabetes, high blood pressure and fatty liver disease.

Diet used in the trial, including whole grains, traditional Chinese medicinal foods and non-digestible carbohydrates, changed the pH in the gut that limited the bacterium’s activity.

Since 1980, obesity worldwide has more than doubled, according to the World Health Organization (WTO). Overweight or obese people are at a higher risk of suffering from heart disease, stroke, cancer, and diabetes.

According to other heath experts not involved in the study, it is possible that the bacteria could be infectious and picked up from some unknown environmental factor, or a parent, and it might not be behavioral after all. The new findings could highlight a way to intervene in obesity and could allow new drugs to be developed for treatment.