Evidence check: IgG Unverträglichkeitstest in the context of gut health

Evidence for IgG-based food intolerance tests in the context of gut health is weak. These tests measure IgG antibodies to foods, but IgG is a normal physiological response to food exposure and does not indicate intolerance or allergy. Medical societies (e.g., DGAKI, EAACI) advise against using IgG tests for diagnosing food intolerances. Claims linking IgG to gut health, inflammation, or 'leaky gut' lack support from controlled trials. Many commercial tests rely on marketing rather than science. For genuine gut health assessment, validated stool tests (microbiome, calprotectin) or IgE allergy testing are appropriate. Caveat: IgG tests may lead to unnecessary dietary restrictions, nutrient deficiencies, and anxiety. Evidence grade: marketing / unclear.