Myths vs facts: Zöliakie Test and Darmgesundheit

A common myth is that a consumer DNA test (e.g., from MyBody-X) can diagnose celiac disease. In reality, such tests only check for HLA-DQ2/DQ8 risk alleles, which are necessary but not sufficient for celiac. Only about 30% of carriers develop the condition. A definitive diagnosis requires positive serology (tTG-IgA) and duodenal biopsy. Therefore, a genetic test alone cannot confirm or rule out celiac. Regarding gut health: celiac is one cause of intestinal damage, but gut health is multifactorial—including microbiome, diet, stress, and other conditions. A DNA test provides only a small piece of the puzzle. Consumers should not rely on such tests for medical decisions. If celiac is suspected, consult a gastroenterologist for proper workup. The evidence for the HLA association is strong, but the predictive value of consumer tests for diagnosis is low and often overstated.