**7. Conclusion**

The effects of probiotics have been widely investigated in a broad spectrum of diseases and are currently suggested as a possible treatment or prevention for several diseases. Different mechanisms are known for the beneficial effects of probiotics, including directly eliminating or preventing pathogens growth by producing antimicrobial substances, eliminating toxins, competing for binding to receptors of epithelial cells, regulating the immune response, reintroducing the microbiota balance, enhancing tight intestinal connections, and also increasing mucus production. Probiotic therapy seems to be a safe and effective method especially, for patients with UC for remission induction and preventing relapse of UC, but, evidence has not proven the efficacy of this supplement on CD patients so far. However, it is needed to taking into account that the biological effects of probiotics on a special disease can be distinctly strain-specific. Therefore, more randomized clinical trials of various probiotic strains in both form of single and mixture on those patients are needed to definitively prove the effectiveness of probiotic microorganisms on these diseases.
