What role does Leaky Gut Test play in Müdigkeit?

A leaky gut test measures markers like zonulin or lactulose/mannitol to assess intestinal permeability. The hypothesis: increased permeability may allow toxins and bacteria into the bloodstream, triggering inflammation and nutrient malabsorption, which could contribute to fatigue. However, the evidence is weak: zonulin tests lack standardization, and a positive result does not prove a causal link to tiredness. Fatigue is multifactorial – sleep, stress, thyroid, iron, vitamin D, and mental health are often more relevant. Consumer leaky gut tests are not clinically validated for diagnosing fatigue. The MyBody-X knowledge base notes that DNA tests for fatigue are also limited; combining with blood biomarkers (e.g., B vitamins, ferritin) is recommended. In summary, a leaky gut test may offer a clue but is not a reliable diagnostic tool for fatigue. Evidence: mechanistic/mixed.