Probiotics discovered by scientists can be roughly divided into three categories, including: ① Lactobacillus (such as Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus jejuni, Lactobacillus Raman, etc. ); ② Bifidobacterium (such as Bifidobacterium longum, Bifidobacterium brevis, Bifidobacterium ovatum, Bifidobacterium thermophilus, etc.). ); ③ Gram-positive cocci (such as Streptococcus faecalis, Lactococcus, Streptococcus intermedia, etc.). In addition, some yeasts and enzymes can also be classified as probiotics. When the human body has enough probiotics, people will be in a healthy state. However, once the flora in the body is out of balance, such as when the proportion of strains changes greatly or exceeds the normal value, a series of diseases such as diarrhea, allergy, loss of appetite, fatigue and low immunity will follow, and human health will turn red. At this time, adding probiotics properly to help balance the flora in the body can restore people's health. Many probiotic strains can produce digestive enzymes in the gastrointestinal tract, which can help people digest food better and absorb nutrients in food. Probiotics can also competitively inhibit harmful microorganisms from absorbing nutrients and entering the blood circulation system.