Gluten intolerance or non-celiac gluten sensitivity refers to a condition associated with gastrointestinal symptoms caused by eating gluten-containing foods despite having negative tests for celiac disease. Therefore, patients with gluten intolerance can't digest gluten-containing foods well, but they don't also have celiac disease. Gluten intolerance or non-celiac gluten sensitivity refers to a condition associated with gastrointestinal symptoms caused by eating gluten-containing foods despite having negative tests for celiac disease. Therefore, patients with gluten intolerance can't digest gluten-containing foods well, but they don't also have celiac disease.