Probiotics are popular nutritional supplements nowadays. Probiotics are defined as: live microorganisms, when consume sufficient amounts, can provide numerous health benefits.  Most of these probiotic microorganisms reside in our intestines. Having a healthy intestinal flora can bring us many health benefits, including improving digestion, enhancing immune function, weight management, promoting healthy skin and reducing the risk of many diseases.
Let’s look at the main benefits of probiotics :
Since the beginning of 2020, COVID-19 has ravaged the globe, and scientists from all over the world are looking for medication and treatment solutions. With the breakthrough of life sciences, especially microbiology research, a new concept of "lung-gut" axis was proposed,  to some extent it coincides with the theory from traditional Chinese medicine. Experts are proposing the use of intestinal microecological regulators to maintain its balance and prevent secondary bacterial infections. It also allows us to see the health value of probiotics in clinical medicine.
references: Bermudez-Brito M, Plaza-Díaz J, Muñoz-Quezada S, Gómez-Llorente C, Gil A: Probiotic Mechanisms of Action. Ann Nutr Metab 2012;61:160-174. doi: 10.1159/000342079 2. Baud D, Dimopoulou Agri V, Gibson GR, Reid G, Giannoni E. Using Probiotics to Flatten the Curve of Coronavirus Disease COVID-2019 Pandemic. Front Public Health. 2020 May 8;8:186. doi: 10.3389/fpubh. 2020.00186. PMID: 32574290; PMCID: PMC7227397.