The total number of intestinal flora in healthy people is as high as 10 14, which is about 10 times of the total number of human cells. The sum of genes encoded by different microorganisms in the intestine is 150~300 times that of the whole human genome, which is also called "the second human genome".
At present, the bacteria that can be detected in human body are Bacteroides, Actinomycetes, Firmicutes, Mycobacterium verrucosum, Proteus and so on. Among them, Firmicutes and Bacteroides account for 90% of intestinal bacteria as dominant flora.
According to the biological function of intestinal flora, it can be further divided into:
1, beneficial bacteria: such as Bifidobacterium and Lactobacillus, accounting for about 90%;
2. Conditional pathogens: such as enterococcus, Escherichia coli and Bacteroides, accounting for about10%;
3. Harmful bacteria: such as Pseudomonas aeruginosa, Staphylococcus, Pseudomonas and Clostridium, accounting for about 0.0 1%.
The normal communication between intestinal flora and its metabolites and the body is conducive to maintaining the health of the host. Intestinal flora can affect human health in different ways by affecting the host's immune system, hormone level and brain center.
When intestinal microecology is disordered, it may cause a series of acute and chronic diseases, such as diabetes, obesity, inflammatory bowel disease, neurodegenerative diseases and tumors.
Simply put, intestinal flora, that is, intestinal microorganisms, is mainly composed of thousands of different microorganisms and 15000 kinds of bacteria, the number of which is about equal to the total number of human cells, forming the first protective barrier of intestinal flora. In the human intestine, there are many beneficial or harmful flora. In recent years, many scholars have shown that intestinal flora is related to obesity, diabetes, depression, cardiovascular diseases, immune metabolic diseases and so on. So, what do you know about intestinal flora?
These huge flora can be roughly divided into three categories: probiotics, neutral bacteria and harmful bacteria.
In recent years, obesity has become the third major disease that threatens human health worldwide after cardiovascular and cerebrovascular diseases and cancer, and about 40% people in the world are facing obesity and overweight problems. The latest research shows that obesity may not only refer to traditional factors such as lack of exercise, overeating and some acquired diseases such as thyroid dysfunction, but also have a great relationship with human intestinal flora. The main cause of obesity caused by intestinal flora is that it decomposes nutrients in human body into short-chain fatty acids. Reducing the intake of high-fat food will reduce the production of short-chain fat in the body. In addition, eating more foods rich in lactic acid bacteria and probiotics can effectively reduce the content of short-chain fat in the body, thus preventing obesity.