What Foods Have Gluten? Complete A-Z List (2026)

Celiac Safety Glossary

Gluten

Gluten is a family of storage proteins (prolamins and glutelins) found naturally in cereal grains like wheat (including varieties like spelt, kamut, and farro), barley, and rye, which acts as a binder to give food elasticity and shape.

Cross-contamination

Cross-contamination (or cross-contact) occurs when gluten-free food comes into contact with gluten-containing food or surfaces — such as shared cutting boards, toasters, fryers, or utensils — rendering otherwise safe food dangerous for people with celiac disease.

Gluten-free certification

Gluten-free certification, such as the GFCO (Gluten-Free Certification Organization) seal, verifies that a product contains fewer than 10 parts per million (ppm) of gluten — stricter than the FDA's 20 ppm threshold for "gluten-free" labeling.

Avenin (Oats)

Avenin is a protein found in oats that is structurally similar to gluten. While most celiacs can tolerate pure, uncontaminated oats, a small percentage of celiacs react to avenin itself.

Malt (Barley)

Malt is fermented barley used as a flavoring or sweetener in cereals, chocolates, and beer; it is a major source of hidden gluten that is often overlooked on ingredient lists.

Wheat starch

Wheat starch is wheat flour that has had the gluten protein washed out. While some European gluten-free foods use codex-grade wheat starch (tested below 20 ppm), it can still trigger reactions in sensitive individuals.

📚Sources & Citations

• •Celiac Disease Foundation — celiac.org — Comprehensive research and patient resources on celiac disease
• •Beyond Celiac — beyondceliac.org — Research-driven celiac disease advocacy and resources
• •GFCO (Gluten-Free Certification Organization) — gfco.org — Certification standards (<10 ppm)
• •FDA Gluten-Free Labeling — fda.gov — Federal regulations for <20 ppm labeling

Content reviewed and fact-checked by our clinical & nutrition team. Last updated July 2026.