Evidence check: Zöliakie Test in the context of weight loss

A celiac test (e.g., tTG-IgA antibodies or HLA-DQ2/DQ8 genotyping) is a diagnostic tool for celiac disease, an autoimmune enteropathy. Untreated, it can cause weight loss, but the test is not validated as a weight-loss strategy. Evidence is based on clinical practice: testing is indicated when celiac is suspected (e.g., chronic diarrhea, malnutrition). Without symptoms or risk factors (e.g., family history), screening for weight loss is unsupported. The MyBody-X context does not mention a celiac test; existing DNA tests (e.g., FADS1, APOE) are irrelevant. A positive result requires medical follow-up and a gluten-free diet, which is not recommended for weight loss in non-celiac individuals. Caveat: No randomized trials support using a celiac test for weight management. Evidence grade: practice/unclear.