Intestinal barrier defects lead to "leaky gut syndrome", defined as an increase in intestinal permeability that allows the passage of luminal content into intestinal tissue and the bloodstream. Such a compromised intestinal barrier is the main factor underlying the pathogenesis of inflammatory bowel disease, but also commonly occurs in various systemic diseases such as viral infections and metabolic syndrome. The non-pathogenic yeast CNCM I-745 has demonstrated its effectiveness as a probiotic in the prevention and treatment of antibiotic-associated, infectious and functional diarrhea. Via multiple mechanisms of action implicated in intestinal barrier function, has beneficial effects on altered intestinal microbiota and epithelial barrier defects in different pathologies. The well-studied probiotic yeast plays a crucial role in the preservation and/or restoration of intestinal barrier function in multiple disorders. This could be of major interest in diseases characterized by alterations in intestinal barrier function.