Probiotics are the patron saint of human health. Probiotics originated from Greek, which means "pro-life". 1908, ElieMetchnikoff, a bacteriologist who won the Russian Nobel Prize in Physiology and Medicine, published a research report saying that lactic acid bacteria in fermented milk can inhibit harmful bacteria in the intestine and promote human health and longevity, which makes the importance of probiotics increasingly valued. The concept of probiotics was first put forward in 1 965, when Lilly DM first described probiotics as "substances or microorganisms beneficial to the balance of animal intestinal flora". 1989, it was revised by Dr. Roy Fowler in Britain as: "Probiotics are living microorganisms that have been supplemented to improve the balance of intestinal flora and have a good health effect on host animals." Modern scientific research has confirmed that probiotics can improve the balance of microorganisms in the intestinal tract of the host, adjust the composition of intestinal flora and promote human health and longevity. Intestinal flora balance There are more than 10 trillion bacteria in the intestine. As you can imagine, the large intestine is full of bacteria. Some are attached to the wall of the large intestine, some are buried in food scraps, and there are hundreds of them. These intestinal bacteria include both "good" bacteria that are beneficial to human health and "bad" bacteria that are harmful to health. The ratio of beneficial bacteria to bad bacteria in the intestine can reflect the health status of the body very dynamically and sensitively. Lactic acid bacteria and bifidobacteria are beneficial bacteria in the intestines of healthy people, and they are in a state of abundant survival. They can inhibit the growth of harmful bacteria. However, due to various reasons, the proportion of beneficial bacteria and harmful bacteria has been out of balance for a long time, and the intestinal environment is prone to change, leading to various sub-health and even diseases, such as "three highs" (hypertension, hyperlipidemia and hyperglycemia) and cancer. "Good bacteria"-Bifidobacterium Among many normal intestinal flora, the most important probiotics are all kinds of Bifidobacterium. A few days after the baby was born, Bifidobacterium became the dominant bacteria of intestinal flora. The content of Bifidobacterium in the intestine is the highest in infancy, reaching109-10/g feces, accounting for 85-99% of the total intestinal bacteria, and it can still reach108-10 after weaning. In old age, the number of bifidobacteria in the intestine is obviously reduced, and some people can't even detect it. It is worth noting that with aging, the number of Bifidobacterium decreased gradually, while the number of Clostridium aerogenes increased gradually, showing a balanced relationship. This shows that the aging of human body is closely related to the decrease of Bifidobacterium. No wonder some people think that the number of bifidobacteria in the intestine is an important index to measure the health level of human beings. The view that Bifidobacterium is related to health and longevity has also been confirmed in the investigation of longevity elderly people at home and abroad. A survey of many healthy centenarians in Bama Yao Autonomous County, a famous longevity area in China, found that the number of bifidobacteria in the intestines of these centenarians was particularly high, reaching 108- 109 per gram of feces, which was equivalent to the level of children and adolescents and 100 times that of the general elderly. There is a similar situation in Shui Yuan Village, Yamanashi Prefecture, Changshou Prefecture. The number and detection rate of bifidobacteria in the intestines of 80-year-old people in this village are similar to those of adults aged 20-40, but the content of harmful bacteria is less than that of ordinary elderly people. The effect of Bifidobacterium on human body is 1, which can treat constipation and chronic diarrhea. 2. Anti-tumor effect; 3. Protect the liver; 4. Prevention and treatment of hypertension and arteriosclerosis; 5. Improve lactose indigestion; 6. Nutritional function; 7, anti-aging effect.