Oats have been a questionable item for Celiacs and the gluten intolerant since the creation of the Celiac disease diet. Oats themselves, as a grain, do not contain the gluten protein. This makes oats gluten free! Unfortunately, at least until just very recently, oats came with an extremely high level of cross contamination and were not allowed on the gluten free diet.
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Oats On a Gluten Free Diet