The gut-skin axis encompasses inflammatory bowel diseases, vascular diseases, malabsorption, food intolerances, and the microbiome(see“Intestinal Diseases” and “Skin Changes”). This bidirectional network consists of neural, endocrine, and immunological signaling pathways as well as metabolic processes. The gut microbiome —including the microbiota and its metabolites such as short-chain fatty acids, bile acids, and tryptophan metabolites—plays a central role.
There is a bidirectional interaction between the gut microbiome and skin diseases; examples include psoriasis, atopic dermatitis, and acne. Correcting dysbiosis through dietary changes, probiotics, and prebiotics can alleviate the severity of skin symptoms. In addition, the skin microbiome plays a crucial role in numerous diseases.