To understand what foods contain gluten, you need to know where gluten comes from.
Gluten is a protein found in the grains wheat, barley and rye (for more information, see my article What Is Gluten?). Because those so-called "gluten grains" wheat in particular are so ubiquitous in our food supply, food manufacturers use gluten in many, many different products, some of which are more obvious than others.
Even if you're just starting out on the gluten-free diet, you almost certainly realize that foods made with flour conventional breads, cookies, cakes, donuts, rolls, bagels, muffins, scones and other pastries, plus conventional pasta and pizza, along with many conventional cereals contain gluten.
If a product includes wheat, it contains gluten and wheat can appear on ingredients labels under many different words, including: flour, bread flour, wheat flour, white flour, whole wheat flour, pasta, bulgur, spelt and kamut. Any of those words on a food label indicate the food isn't safe for someone on a gluten-free diet.
Barley appears less frequently than wheat on the dinner table. However, beer always has barley in it (unless it's gluten-free beer), and barley is used to make malt. In addition, soups and casseroles sometimes include pearl barley (almost always listed as such on a label), and barley extracts can serve as a sweetener in some processed foods, frequently hidden under the words "natural flavor."
Generally, rye the least common of the gluten grains appears only in rye bread and in some forms of alcohol; it's rarely used in other processed foods.
There are multiple other foods that frequently (but not always) have gluten. These include: canned soups (flour is used as a thickener instead of cream), sausage (bread crumbs are used as a filler), soy sauce (wheat is the first ingredient) and even low-fat ice cream (starch, often wheat starch, is used to provide texture).
In addition, many processed foods contain gluten as an ingredient, including spice mixtures, salad dressings, sauces and other condiments, plus frozen dinners and various prepared side dishes. It's even possible for yogurt and other milk products to contain gluten ingredients.
Therefore, if you want to avoid gluten in your diet, you'll need to check the ingredients of every food product you use!
Here's some more information on what foods contain gluten:
If you're planning to start a gluten-free diet, here's what you need to know: