There is a relationship between the maintenance of the integrity of the intestinal barrier function and the balance of the intestinal microbiota, particularly regarding the type, quantity, and other parameters of bacterial metabolic products. Increased inflammation increases intestinal permeability. The anti-inflammatory approach enhances the integrity of the gut. To have a healthy barrier function, one needs to have a healthy microbiota profile. Intestinal permeability is monitored through laboratory tests conducted on stool samples. For this purpose, a fecal zonulin test is being conducted. The reference value for the zonulin test in stool is <42 µU/g. Again, the alpha1 antitrypsin test conducted on stool also indicates intestinal barrier function. The occludin (Occludin) test from serum is also a sensitive test that can be used for intestinal permeability. For the brain barrier, the GFAP test (Glial Fibrillary Acidic Protein) or the S100B test, which show the functions of astrocyte cells, can be performed.

In the case of increased intestinal permeability, the repair and strengthening of impaired barrier functions can be achieved through certain appropriate medical interventions. After the correct diagnosis, the repair of both barriers can be ensured with experienced, good interpretation, and correct methods and practices. This process is critically important for brain health. The brain should be protected by the repair of two barriers and should contribute to preventing unwanted molecules from reaching the brain and triggering unwanted reactions within the brain. On one hand, while appropriate reparative interventions are applied for the brain, on the other hand, the disorders in barrier permeability that contribute to the triggering and maintenance of pathological reactions within the brain should be repaired, and front brain barriers should be established.