Leaky Gut Test: what does this mean exactly?

A 'Leaky Gut Test' (e.g., measuring zonulin, LPS, or alpha-1-antitrypsin in stool) is marketed as a way to detect increased intestinal permeability. However, the scientific evidence is weak: zonulin is not a specific marker, tests lack standardization, and their clinical validity is unproven. Many commercial tests are used to sell expensive diets or supplements. There is no universally accepted definition or diagnostic criteria for 'leaky gut syndrome.' While some research links intestinal permeability to conditions like IBS or autoimmune diseases, routine testing is not recommended by major medical societies. A positive result may indicate altered permeability, but interpretation is uncertain. Instead, focus on established medical evaluations (e.g., lactulose-mannitol test under medical supervision). The risk is unnecessary dietary restrictions or false reassurance. Bottom line: these tests are currently more marketing than evidence-based medicine.