Can IgG Unverträglichkeitstest help with gut health?

IgG food intolerance tests (e.g., NutriCheck) are often marketed to improve gut health, but they lack scientific validation for that purpose. The measured IgG4 antibodies merely indicate immune exposure—meaning the body has encountered certain food proteins—not intolerance or harm. Major allergy and immunology societies (e.g., DGAKI, EAACI) advise against these tests because they frequently lead to unnecessary and potentially harmful elimination diets. True gut health depends on microbiome diversity, inflammatory markers, mucosal integrity, and nutrient status—none of which are assessed by IgG tests. Eliminating multiple foods simultaneously can cause deficiencies in iron, B12, calcium, and other nutrients. A more evidence-based approach includes symptom-guided challenges, breath tests for lactose/fructose malabsorption, or targeted stool analysis under medical supervision. The evidence for IgG-based intolerance tests is best classified as 'marketing'—they primarily benefit the seller, not the patient.