How to Spot Those Sneaky Sources of Gluten

Tips for avoiding the protein from wheat, rye and barley
woman checking labels for hidden gluten ingredients

If you have celiac disease, even traces of gluten (a protein found in wheat, barley, rye and sometimes oats) can wreak havoc on your intestinal tract.

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When pain and distress persist despite remaining on guard against gluten in restaurants, dietitian Mia DiGeronimo, RD, LD, recommends considering these hidden sources. (And avoid any that aren’t labeled “gluten-free.”)

What foods have gluten that you wouldn’t expect?

1. Medications + supplements

Gluten may be used as a filler or coating in medications and supplements. Always review the ingredients list on any over-the-counter medications, or vitamin/mineral supplements. Any prescribed medications should be reviewed by your doctor to be sure they don’t contain gluten — and find gluten-free substitutes if you have celiac disease.

Research also suggests those with celiac disease have a greater need for nutrients like B vitamins, vitamin D and iron.

2. Meat, fish + poultry

Watch for hydrolyzed wheat protein in meat, fish and poultry. Processed lunch meats and deli meats like cold cuts, hot dogs, salami and sausage may contain gluten. Other foods like self-basting poultry or seasoned turkey breast may also contain gluten.

3. Meat (and fish) substitutes

Watch for gluten in veggie burgers, sausage, bacon and crumbles, and in imitation seafood and seitan.

4. Chips + fries

Potatoes and corn are naturally gluten-free, but potato chip seasoning may contain malt vinegar and wheat starch. Also be aware that tortilla chips and French fries may be fried in the same oil/fryer as foods that contain gluten. This will contaminate the oil and may cause harm to someone with celiac disease.

5. Oats

Oats are naturally gluten-free whole grain that contain important vitamins, minerals and fiber. But oats are at high risk for cross contamination. They’re sometimes grown next to wheat or packaged in facilities that have gluten-containing products. When shopping, beware of bulk bins. Only choose oats that are labeled “certified gluten-free.”

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6. Beverages + alcohol

Gluten may be in flavored coffees and teas. Beer, ale, lager and malt beverages may also contain gluten. Wine is naturally gluten-free. Distilled alcohol (for example, gin and vodka) are considered safe for people with celiac disease.

7. Eggs at a restaurant

Omelets and eggs may be made with pancake batter. Always ask the server to confirm.

8. “Gluten-free” pizza + baked goods

These may be contaminated by other grains.

9. Sweet treats + snacks

Flavored ice creams (like cookie dough) and gelatos may contain gluten. Look for gluten in candy (especially licorice), energy bars and granola bars, too. It is important to read labels every time you purchase the item to verify that all ingredients are gluten-free since manufacturing practices may change.

10. Soy sauce + miso

Soy sauce (except for tamari) is made with wheat. Miso, a soup base, may be made with barley.

11. Salad fixings

Salad dressings may contain gluten. Beware of salad bars as cross contamination may occur. If dining out, be sure to ask your server to avoid putting croutons on your salad.

12. Ezekiel bread

The popular sprouted bread is made from wheat and barley.

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13. Soups + gravies

Gluten may be used as a thickener, even in bouillon.

Tips for avoiding surprising sources of gluten

Know wheat in all its forms. Wheat berries, semonila, spelt, farina, graham, durum, emmer, faro, Khorasan, udon and einkorn all contain gluten. (Watch for “modified” products, too.)

Look out for tricky ingredients. If a product is NOT labeled gluten-free, but contains one of these in the ingredients list, do not buy it: starch, modified food starch, hydrolyzed vegetable protein, hydrolyzed plant protein, textured vegetable protein, dextrin, maltodextrin, glucose syrup, caramel, malt flavoring, malt extract, malt vinegar (distilled vinegar is OK), brown rice syrup.

When in doubt, leave it out. If you can’t confirm products are gluten-free, substitute fresh, nutrient-rich whole foods like meat, fish, poultry, fruits, and vegetables. Choose naturally gluten-free starches like rice, quinoa, corn, buckwheat, potatoes, sorghum and wild rice.

Prevent kitchen cross-contamination. Crumbs linger in shared toasters, cutting boards, and community peanut butter, jam and cream cheese. Wipe counters regularly, and clean gluten-free dishes with a separate sponge. Line shared flour sifters and backing pans with parchment paper or foil, and wrap gluten-free bakery in foil.

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