ABSTRACT
Microbiome members are surpassing the number of cells making up the human body, and there are 100–150 times more genes in the microbiome, as compared to the number of genes in the human genome. Among the microorganisms in the human intestine, more than 98% are bacteria. They can be roughly divided into three categories, which are Probiotics, Harmful bacteria, and Neutral bacteria. The human intestine normally contains microorganisms such as bifidobacteria, and lactobacillus. The ecological balance between the human body and the microorganisms is regulated by host factors and environmental factors. The relationship between intestinal microbes and the immune system can also be shown by lab experiments with mice. Antibiotics can be used to fight bacterial infections in the body. It can be seen that intestinal microbes are also affected by antibiotics. A high-fat diet changes the intestinal microbiota and stimulates the growth of intestinal tumors.
