Obesity can easily lead to fatty liver and even liver cancer, and Japanese researchers have confirmed through animal experiments that this is due to the increase of Gram-positive bacteria in the intestinal tract after obesity makes liver cells age, which leads to cancer. The study was published in the June 27 issue of the online edition of the British journal Nature. The researchers coated two groups of rats with low concentrations of cancer-inducing chemicals, then fed one group of rats a high-fat diet and the other a normal diet, and the rats that became obese all developed liver cancer, while the other group of rats did not have liver cancer. The number of Gram-positive bacteria in the intestines of the obese rats was more than 3,000 times that of the normal-weight rats. The team found similar cellular damage in obese liver cancer patients and therefore hypothesized that there is a similar pathogenesis of liver cancer in humans.