Primary objective of the study is to evaluate the efficacy of acute intake of a small amount of flour derived from Triticum monococcum (a variety of ancient wheat) in patients with celiac disease, in gluten free diet. A small amount of toxic gluten (2.5 milligrams) can modify intestinal permeability in celiac patients, so this parameter can be a good indicator to verify if gluten from Triticum monococcum can be considered a non toxic gluten and to test the hypothesis of its introduction in a gluten free diet.