Zöliakie Glutenunverträglichkeit-Test: which blood markers matter?

For diagnosing celiac disease (gluten-sensitive enteropathy), validated blood markers include IgA antibodies against tissue transglutaminase (tTG-IgA) as the first-line test, along with IgA endomysial antibodies (EMA) and deamidated gliadin peptide antibodies (DGP-IgA/IgG). In case of IgA deficiency, IgG-based alternatives (e.g., tTG-IgG, DGP-IgG) are used. These markers are only reliable when the patient is on a gluten-containing diet. Importantly, commercial IgG food intolerance tests (e.g., for gluten) are not scientifically validated for celiac diagnosis and are not recommended by medical guidelines. They reflect immune exposure, not disease. The evidence for the celiac-specific markers is strong (human-strong), whereas IgG panels are considered marketing-grade without clinical validation. A definitive diagnosis still requires duodenal biopsy. Always consult a physician before making dietary changes based on such tests.