Leaky gut is a real medical term, but one that unfortunately has been picked up by the woo/toxin/alternative medicine crowd. Some researchers use the term intes

Leaky gut is a real medical term, but one that unfortunately has been picked up by the woo/toxin/alternative medicine crowd. Some researchers use the term intestinal permeability instead. Both terms refer to barrier dysfunction in the tight junctions that make up the cell wall of the intestines. By becoming more permeable, the gut wall lets bacteria through and allows them to either colonize the surrounding tissue and/or enter the blood stream, a phenomenon known as bacterial translocation. Patients with intestinal permeability may have detectable levels of bacteria in their blood. A healthy gut absorbs nutrients and water through the gut wall, but protects the body against pathogens. Studies show that some autoimmune conditions like psoriasis and Crohn's are associated with increased intestinal permeability. Unfortunately, "leaky gut syndrome" took this idea and ran with it, and as a result we have a lot of snake oil going around. As for this paper, the connection is really interesting, and seems to fill in some gaps. For example, one of the newest medications for psoriasis, Vtama, is an aryl hydrocarbon receptor agonist. Psoriasis has also been successfully treated with bile acids in at least two studies.