Hi, I am little confused, does oat contain gluten?
Naturally no; commercially, yes. If oats are processed and mixed with ingredients such as wheat, barley, and rye then they contain gluten, this is what NCBI Says.
Naturally, oats are gluten-free, but the problem is that oats are almost always processed in the same facilities as other grains that contain gluten (wheat, barley, rye), so they easily get contaminated and therefore not gluten-free.