Hidden sources of Gluten / Wheat

Wheat, barley and rye proteins. (Rule out coeliac disease with a clinician before removing gluten long-term.)

Where it hides

Traditional soy sauce, teriyaki sauce, and many marinades — standard soy sauce is fermented with wheat unless specifically labeled gluten-free
Broths, bouillon cubes, and gravy mixes — hydrolyzed wheat protein or flour is often used as a thickener or flavor carrier
Spice blends and pre-shredded cheese — an anti-caking agent is often added — usually cellulose or potato starch, but occasionally wheat starch or flour — so it's worth a label check rather than assuming wheat
French fries, eggs, or "gluten-free" items at restaurants — shared fryer oil or a shared grill/prep surface with breaded foods causes cross-contact even when the dish itself is gluten-free
Deli meats and imitation seafood (surimi) — wheat starch or flour is used as a binder/filler in processed proteins
Beer, malt vinegar, and malted milk products — malt is derived from barley, one of the gluten-containing grains, and is easy to overlook since it reads as a flavoring, not a grain

Information only — not medical advice or a diagnosis. Settle structures a self-experiment and helps you track what you observe.