Fermented by Xanthomonas campestris, xanthan gum can be used as a thickening agent in place of gluten. Since the process is more dependent on technology than whole foods, I was wondering if it should be excluded from a paleo diet (or if there were other reasons for its exclusion).
I assume you mean xanthan gum.
Hmm, a polysaccharide from the coating of a bacteria created in a lab in the 60's (probably not by hippies). Oh yeah! Totally paleo!
All snarkiness aside, I would put it up there with carageenan (another "natural" substance best avoided). It may or may not cause you any particular difficulty - but why would you want to ingest it? The precautionary principle would be "Just say no."
The wiki article notes some people have allergic reactions to it. And large amounts of it are a great laxative - so there's that.
I've been baking gluten-free for 5 years and never used the stuff, so I don't see any reason for doing so. Many GF recipes seem to use it pretty gratuitously - it's added to cakes, muffins, cookies and so forth where the whole goal (when working with wheat flour) is to stir as lightly as possible so as NOT to develop the gluten. If I need extra hold-togetherness in a recipe, I use an extra egg or flax-seed meal.
I follow a low carb/specific carbohydratish diet for colitis. Xanthan is not supposed to be legal on scd but I have experimented with and it doesn't cause a flare of symptoms for me. Using very small amounts occasionally as a thickener allows me to have some items that I otherwise couldn't like cobblers or gravies. Having these treats from time to time really helps me stay on my diet and symptom free. I can't tolerate flours or arrowroot or cornstarch.
Your question is a good one. with grains and starchy roots forbidden there is nothing left to thicken liquids with. The "good for you" or "bad" is determined by the type of lectin it contains and whether that posses a problem for health. If some people want to make a religion out of eating paleo then by all means they should. I'm interested in health.
That said, the bacteria xanthum gum is derived from is cultured on corn, wheat, dairy or soy. Xanthum gum has been found to contain gluten. As such while xanthum gum in itself may be fine it most probably contains lectins from the growth medium, all of which is a problem.
But if it not a problem for you then it is not a problem. You may find some brands/batches cause ill effects while others do not due to what it is grown on.
P.S. To all Paleo snarks. What our ancestors ate is not known. Mostly is is an educated guess. Some foods are know with certainty (dairy) others not.