Foods that contain wheat, barley, triticale and rye grains contain gluten; oats may also be a source if they have come into contact with gluten-containing grains, according to WebMD. Common foods that contain gluten include breads, pastas, bagels, malted breakfast cereals and pizzas.
Because some oats are exposed to wheat, rye or barley during the processing cycle, oats can be a source of gluten, warns WebMD. However, many people who are intolerant of gluten can eat oats in moderation without experiencing any symptoms. Those newly diagnosed with celiac disease should generally avoid oats until a gluten-free diet has been commenced and the symptoms of celiac disease are under control. Then, if desired, oats in 2-ounce increments can be added to ensure tolerance in the diet. Shopping for oats that are known to not be exposed to gluten-containing grains is advisable.
Many people who are gluten sensitive may need to avoid or limit milk products during initial treatment. This gives the intestine a sufficient amount of time to recover; typically up to 6 months without milk is recommended.
Unless labeled as gluten free, beer should also be avoided, notes WebMD. This includes beers both with and without alcohol, including stouts, ales and lagers. WebMD also warns that gluten is sometimes hiding in non-foods, including lip balm, lipstick, nutritional supplements and medicines.