There always seems to be a new layer of learning when it comes to gluten-free. Just when you think you’ve got it all covered and are safe, out pops another fact that complicates matters. I've recently learned that xanthan gum may be a problem, and here's how it plays out.
Gluten is a protein in wheat flour that holds baked goods together—it’s the “glue” that provides structure and stretch. Gluten-free baked goods need a substitute for this strong binder; otherwise they crumble. (That’s the basis for the name of my website: When my family first started eating gluten-free baked goods, we kept saying, “It crumbles!”)
Xanthan gum is a standard ingredient in gluten-free baked goods because of its binding qualities. Xanthan gum is a bacteria grown in a lab, most commonly from corn, but it can be made from wheat (!), dairy, or soy. If xanthan gum is made from wheat, it is possible that the gluten protein could still be present even though the product says it’s gluten-free! This can cause problems for gluten-sensitive people. It may be the reason why certain individuals can tolerate xanthan gum only some of the time—their intolerance depends on xanthan gum’s origin.
I consider xanthan gum a possible hidden source of gluten, and sometimes I wonder if it is affecting me. It's used as a stabilizer in salad dressings, cosmetics, and even, believe it or not, laxatives.
Bottom line: Beware that xanthan gum, present in many “gluten-free” products, could be derived from wheat and could, therefore, cause problems for you if you are sensitive to gluten.