Going Gluten-Free: The Complete Beginner's Guide (2026)

Celiac Safety Glossary

Celiac disease

Celiac disease is a serious autoimmune disorder in which ingesting gluten — a protein found in wheat, barley, and rye — triggers an immune response that damages the small intestine's villi, affecting approximately 1 in 100 people worldwide according to the Celiac Disease Foundation.

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.

Brewer's yeast

Brewer's yeast is a byproduct of beer brewing that is heavily contaminated with gluten from barley; it is a common hidden ingredient in savory snacks and seasonings.