Gluten is found in wheat, rye, barley, some processed oats and any food made with these grains. Wheat-based flours, pasta, couscous, bread, flour tortillas, muffins, cereal, crackers, beer, oats and most pastries commonly contain gluten. There are replacements for many of these foods that are made without gluten.
There are many foods that may not be expected to have gluten as an ingredient, but which actually do have ingredients with gluten in them. Some of these foods are broths, bouillon cubes, breadcrumbs, croutons, fried foods, imitation fish, lunch meats, hot dogs, malt, matzo, modified food starch, seasoned chips, salad dressing, self-basting turkey, soy sauce, seasoned rice and pasta mixes. There are many additives that have gluten in them as well.
It is always beneficial to check the label or ingredient list on foods before eating them to find out if there is gluten in the food. The label "wheat-free" does not always mean that the foods are gluten free. If there are any concerns or questions, contact the manufacturer to be positive that there is no gluten in the food items. While pure oats are gluten free, many commercially processed oats have been contaminated by wheat products containing gluten. It is often recommended to avoid oats if gluten-free eating is required.