Gluten is found in wheat (including all its varieties), barley, rye, and anything made from or with these grains. That covers obvious foods like bread and pasta, but it also shows up in less expected places: soy sauce, beer, salad dressings, and even some medications. Knowing the full picture helps you avoid surprises.
The Core Gluten Grains
Three grain families contain gluten: wheat, barley, and rye. Triticale, a hybrid of wheat and rye, also contains it. What trips people up is that wheat goes by many names on ingredient labels, and some of its varieties sound like entirely different grains. All of the following are forms of wheat and contain gluten:
- Spelt
- Farro
- Einkorn
- Emmer
- Durum
- Kamut (khorasan wheat)
- Semolina
- Farina
- Graham
- Wheatberries
If you see any of these on a label, that product contains gluten. Some health food brands market spelt or einkorn bread as easier to digest, and while the gluten structure in ancient wheat varieties differs slightly from modern wheat, they are not safe for anyone who needs to avoid gluten entirely.
Everyday Foods That Contain Gluten
The obvious ones are bread, pasta, cereal, crackers, baked goods, pizza dough, flour tortillas, and beer. But gluten also hides in foods you might not suspect, usually because wheat flour or barley derivatives are used as thickeners, binders, or flavoring agents.
Most commercially available soy sauce is fermented with wheat. Traditional miso can be made with barley. Many gravies, cream-based soups, and pre-made sauces use wheat flour as a thickener. Breaded or battered foods (chicken tenders, fish sticks, onion rings) are coated in wheat. Couscous is made from wheat semolina. Seitan, popular as a meat substitute, is essentially pure wheat gluten.
Other common sources include pancake and waffle mixes, croutons, stuffing, pretzels, licorice candy, some potato chips with malt vinegar flavoring, and communion wafers. Processed lunch meats and veggie burgers sometimes use wheat-based fillers. Even foods you’d assume are naturally gluten-free, like french fries, can be coated in a wheat-based batter or fried in shared oil with breaded items.
Malt and Brewer’s Yeast
Barley shows up in processed foods primarily through malt. Malt extract, malt syrup, malt flavoring, malt vinegar, and malted barley flour are all derived from barley and contain gluten. You’ll find malt in some breakfast cereals (including certain rice-based ones), malted milkshakes, flavored snack foods, and beer. If an ingredient list says “malt” without specifying a gluten-free source, assume it comes from barley.
Brewer’s yeast, a byproduct of beer brewing, also contains gluten. It appears in some nutritional supplements and savory spreads. Nutritional yeast, by contrast, is typically grown on molasses and is gluten-free, though it’s worth checking labels to confirm no cross-contamination.
Tricky Additives on Ingredient Labels
Several common food additives can be derived from wheat, though most of the time they aren’t. Understanding which ones to watch for and which ones are safe regardless of their source saves a lot of label anxiety.
Modified food starch is usually made from corn in the United States. When it comes from wheat, FDA-regulated products are required to state “wheat” on the label, either in the ingredients list or in a “Contains” statement. One exception: USDA-regulated products like meat and poultry may use wheat-based modified food starch without declaring wheat on the label.
Dextrin is another starch derivative that can come from wheat, though most U.S. manufacturers use corn. If a product contains wheat-derived dextrin but carries a “gluten-free” label, it must meet the FDA threshold of fewer than 20 parts per million of gluten. Without that label, check with the manufacturer.
Maltodextrin is considered gluten-free regardless of whether it starts as wheat or corn starch. The processing breaks it down enough that gluten is no longer present at detectable levels. The same applies to glucose syrup, which is sometimes made from wheat or barley starch but is processed so thoroughly that it falls well below 20 ppm of gluten.
The Oat Question
Oats themselves do not contain wheat, barley, or rye gluten. But they’re frequently grown near wheat fields, processed in shared facilities, or transported in shared equipment. The result is significant cross-contamination. One study testing 15 products marketed as gluten-free oat-only foods found that 67% exceeded the 20 ppm gluten threshold, meaning they wouldn’t actually qualify for a gluten-free label under FDA rules.
If you need to avoid gluten, look for oats specifically labeled as certified gluten-free. These are grown, harvested, and processed using dedicated equipment to prevent contamination. Regular grocery store oats, even if they seem like a naturally gluten-free grain, frequently carry enough contamination to cause problems.
Beverages and Alcohol
Beer is brewed from barley and contains gluten unless it’s made from alternative grains like sorghum or rice and labeled gluten-free. Some beers are marketed as “gluten-removed,” meaning they’re brewed with barley and then treated with enzymes to break down gluten proteins. These remain controversial because testing methods may not reliably detect the fragmented gluten that remains.
Wine and distilled spirits (vodka, gin, whiskey, rum) are generally considered gluten-free. Distillation removes gluten proteins, so even whiskey made from wheat or barley is safe for most people. Flavored spirits, wine coolers, and pre-mixed cocktails may have gluten-containing additives, so check the label. Malt beverages like hard lemonade or malt liquor contain barley-derived gluten.
Medications and Non-Food Products
Wheat starch is used only very rarely as a filler in oral medications in the United States. The FDA has noted that it is aware of no oral drug products currently on the U.S. market that intentionally contain wheat gluten as an inactive ingredient. Corn and potato starches are far more common in pharmaceutical manufacturing.
That said, some pill ingredients like modified starch, pregelatinized starch, and sodium starch glycolate could theoretically be derived from wheat. Starch breakdown products used in medications, including maltodextrin, dextrose, and sugar alcohols like sorbitol and mannitol, are processed enough that they’re unlikely to contain meaningful gluten even if wheat was the starting material.
Lip balms and lip sunscreens occasionally contain wheat germ oil. If the oil is highly refined, it’s unlikely to have detectable gluten. Even unrefined versions applied to the lips would contribute an insignificant amount of gluten through incidental ingestion. Cosmetics applied to skin (not lips) pose no risk because gluten must be ingested to cause a reaction in people with celiac disease.
Grains and Starches That Are Gluten-Free
Many grains and starches are naturally free of gluten. Rice, corn, quinoa, buckwheat (despite the name, it’s not related to wheat), millet, sorghum, teff, and amaranth are all safe. So are potatoes, tapioca, arrowroot, cassava, beans, soy, chia, flax, and nut flours. These form the base of most gluten-free cooking and baking.
Buckwheat deserves a special mention because its name causes confusion. It’s actually a seed related to rhubarb, not a grain, and contains no gluten. Pure buckwheat soba noodles are gluten-free, but many commercial soba noodles blend buckwheat with wheat flour, so read the ingredients carefully.
How to Read Labels Confidently
In the U.S., any product labeled “gluten-free,” “no gluten,” “free of gluten,” or “without gluten” must contain fewer than 20 parts per million of gluten. That’s the lowest level that can be reliably measured with validated testing methods, and it’s the same standard used across most of the world.
For products without a gluten-free claim, the FDA requires that wheat be declared on labels of foods it regulates. Barley and rye, however, are not among the major allergens that require mandatory disclosure, so they can appear under vague terms like “natural flavoring” or simply be listed as “malt.” When in doubt, look for a certified gluten-free seal from organizations like the Gluten-Free Certification Organization, which tests products to a stricter 10 ppm standard.