IgG Unverträglichkeitstest: can a microbiome test help?

IgG food intolerance tests are often marketed to identify food sensitivities, but the scientific evidence is weak. IgG antibodies to foods are commonly part of a normal immune response and do not reliably indicate intolerance. Medical guidelines generally advise against these tests. A microbiome test cannot help here: it measures gut bacterial composition, not IgG reactions. While the microbiome may play a role in genuine intolerances (e.g., lactose intolerance) or irritable bowel syndrome, microbiome tests are not validated for diagnosing food intolerances. The evidence for microbiome testing in this context is limited to observational studies, not clinical trials. In short, a microbiome test cannot confirm or replace IgG test results. For suspected food intolerance, a supervised elimination diet or validated tests (e.g., lactose breath test) are more appropriate. Caveat: consumer tests for both IgG and microbiome lack robust clinical validation and should not guide dietary changes without professional advice.