Evidence check: IgG Unverträglichkeitstest in the context of allergy

IgG food intolerance tests are often marketed to identify 'delayed' food sensitivities, but they lack scientific validation for diagnosing allergies or intolerances. IgG antibodies indicate prior exposure to a food, not an adverse reaction. Major allergy organizations, including the American Academy of Allergy, Asthma & Immunology, advise against using these tests because they can lead to unnecessary dietary restrictions and nutritional deficiencies. The evidence is mechanistic at best; no robust clinical trials support their clinical utility. Consumers should rely on validated methods such as IgE testing, skin prick tests, or physician-supervised elimination diets. Caveat: A positive IgG result does not mean the food should be avoided.