wie testet man glutenunverträglichkeit — what does this mean exactly?

Testing for gluten intolerance is not straightforward because the term covers different conditions. For celiac disease (an autoimmune disorder), established tests exist: blood antibodies (tTG-IgA, total IgA) followed by duodenal biopsy if positive. HLA typing (DQ2/DQ8) can assess genetic risk but is not diagnostic alone. For non-celiac gluten sensitivity (NCGS), there is no reliable biomarker; diagnosis is made by exclusion and controlled gluten challenge. Direct-to-consumer DNA tests claiming to detect 'gluten intolerance' based on single SNPs are not scientifically valid. They may test HLA variants but lack clinical correlation and do not measure antibodies or symptoms. Such tests cannot diagnose celiac disease or NCGS. Anyone with genuine symptoms should see a doctor for proper workup. Self-imposed gluten-free diets without medical guidance risk nutrient deficiencies and delayed treatment.