What do studies say about Gluten Test?

Scientific evidence on gluten sensitivity tests, especially IgG-based food intolerance panels, is weak. These direct-to-consumer tests are often marketed for detecting non-celiac gluten sensitivity but lack robust clinical validation. For celiac disease diagnosis, guidelines from ESPGHAN and other bodies recommend IgA antibodies against tissue transglutaminase (tTG) and confirmatory duodenal biopsy, not IgG panels. IgG antibodies to gluten can be present in healthy individuals without any intolerance, leading to high false-positive rates. The few studies that exist show poor reproducibility and no consistent association with symptoms. Therefore, the evidence level for such tests is best described as 'marketing' or 'mixed' – they are commercially driven rather than evidence-based. Consumers should not rely on these results for dietary decisions without consulting a healthcare professional. If gluten-related disorders are suspected, validated medical tests (e.g., IgA-tTG, HLA-DQ2/DQ8 genotyping) should be used. The provided context does not contain direct studies on gluten tests but does reference the lack of validation for IgG food intolerance tests.