I'm a label reader and I like to know what I am putting in my body. I have been seeing "xanthan gum" listed as an ingredient in many different types of food, like this Annie's salad dressing. I finally decided to find out what it is exactly.
Xanthan gum is made by fermenting corn sugar with the Xanthomonas campestris bacterium (that's where it gets its name). This bacteria is the same one that causes black spots to form on broccoli or cauliflower. It's added to products as an emulsifier to help ingredients blend more effectively, and it's also used as a thickener. Xanthan gum is usually found in salad dressings and sauces, but you may also see it in frozen foods to prevent ice crystals from forming. It's also added to fat free foods to give them a smoother consistency. Some toothpastes contain this additive, and xanthan gum is also used in gluten-free baked goods to give the dough a sticky consistency.
Since it's made from corn sugar and added to foods in small amounts, it's not unhealthy for us. The only people who need to watch out are those who have a corn allergy.