Gluten is a protein found in some grains, notably wheat, barley, and rye. The symptoms of celiac disease (such as diarrhea, weight loss, and abdominal bloating) may or may not occur after eating foods that contain gluten. But if you have celiac disease, eating gluten triggers an immune response that is not normal and can lead to damage of your small intestine. This damage can occur even when you do not notice symptoms.

Some foods and food products may contain gluten even when it is not specifically listed as an ingredient. The following foods and food products may have hidden gluten:

Milk products

• Ice cream and other frozen dairy products
• Cheese spreads
• Yogurt with fruit

Processed foods

• Hot chocolate mixes or cocoa, chocolates, and candy bars
• Bouillon cubes, soup mixes, and canned soups
• Processed meats and poultry, such as hot dogs, sausages, and luncheon meats
• Imitation meat and seafood

Other products

• Nondairy creamer, salad dressings, soy sauce, gravy and other sauce mixes, mustard, ketchup, tomato sauce, and peanut butter
• Drink mixes and herbal teas
• Hydrolyzed vegetable protein, which is a filler product used in many prepared or processed foods
• Communion wafers used in religious services

If you have celiac disease, it is important for you to learn about sources of hidden gluten. You may not always have symptoms, so you cannot judge whether a food is safe by how you feel after eating it.

Some medicines contain gluten. Ask your doctor whether the medicines you take contain gluten. You can also ask your pharmacist when buying nonprescription medicines, but often you must contact the manufacturer of the medicine to find this information.

Gluten may also be in products such as vitamins and other health supplements, lipstick, lip balm, and children's modeling dough (such as Play-Doh).