Probiotics have been advocated as a relatively new approach to treating disease. As more and more information on the microbiome becomes available, probiotics look increasingly promising. However, one study questioned how probiotics can affect healthy specimen. The animal study tested how probiotics can affect the composition of other microbiotas in the body, namely the respiratory and blood microbiotas.
The study found that probiotics can inhibit colonization of pathogens by crowding out harmful bacteria with normal gastrointestinal flora. Interestingly, oral probiotics can actually prevent disease or decrease severity of diseases occurring outside of the gastrointestinal tract. The administration of a probiotic actually affected the microbiota of the respiratory tract as well. This all adds to the growing evidence that probiotics can improve the health of patients with dysbiosis. It has been proposed that the gut cross-talks to the body, allowing it to influence things such as immune function. The gut microbiome is proving to be incredibly important to immune homeostasis, and it seems that probiotics can assist with that.
Vientós-Plotts, A. I., Ericsson, A. C., Rindt, H., & Reinero, C. R. (2017). Oral Probiotics Alter Healthy Feline Respiratory Microbiota. Frontiers in Microbiology, 8, 1287. http://doi.org/10.3389/fmicb.2017.01287