How Our Gluten-Free Verdicts Work

The four verdicts

• NOT GLUTEN-FREE

  A Tier 1 ingredient (wheat, barley, rye, malt, regular soy sauce…) or an allergen statement naming a gluten grain is on the label. Claims never override Tier 1.

• RISKY — CHECK SOURCE

  A conditional (Tier 2) ingredient is present — like uncertified oats or an unsourced starch — and the product isn’t certified gluten-free. The ingredient can be fine; the label doesn’t prove it.

• LIKELY GLUTEN-FREE — VERIFY

  No gluten ingredients found, but something keeps us from full confidence: no gluten-free claim on the package, a “may contain” gluten-grain warning, an ingredient we couldn’t identify, or an AI-assisted classification.

• GLUTEN-FREE

  A clean pass against the lexicon plus a gluten-free label claim — or third-party certification covering conditional ingredients. Only fully deterministic scans can be green.

Ingredient tiers

• Tier 1 — Unsafe

  Ingredients that contain gluten: wheat in all its species (durum, semolina, spelt, kamut, farro, einkorn, emmer, triticale), barley, rye, malt in every form, brewer’s yeast, regular soy sauce, seitan, couscous, bulgur, graham, matzo, panko, farina. The only exceptions are wheat-derived ingredients that U.S. law explicitly allows in labeled gluten-free food (see wheat starch below).

• Tier 2 — Conditional

  Ingredients whose gluten status depends on sourcing or handling: oats (cross-contact), unsourced “starch” or “modified food starch,” dextrin, hydrolyzed vegetable protein, yeast extract, brown rice syrup, wheat/barley grass. A named gluten-free source (e.g. “modified food starch (corn)”) resolves them; certification covers them.

• Tier 3 — Advisory

  “May contain wheat,” shared-facility and shared-equipment statements. These are voluntary and unregulated. They never make a verdict red on their own, but a gluten-grain “may contain” keeps a product from being called fully gluten-free.

• Tier 0 — Safelist

  Hundreds of ingredients with no gluten relevance, including famously misunderstood ones: maltodextrin (no malt in it), glucose syrup (gluten removed by processing even when wheat-derived), distilled vinegar, and U.S. caramel color. These resolve instantly and never trigger false alarms.

Current lexicon: 18 unsafe, 8 conditional, 3 advisory and 87 safelisted entries covering 1103 label phrases — every entry cited to a primary source.

Regulatory anchors

• FDA gluten-free rule — 21 CFR 101.91

  A food labeled “gluten-free” must contain less than 20 ppm of gluten. The rule explicitly permits properly processed wheat starch — which is why a labeled product containing wheat starch can genuinely be gluten-free.

• FALCPA — wheat-only disclosure

  U.S. allergen law requires declaring wheat — but NOT barley or rye. A “Contains” statement without wheat proves nothing about gluten. This is the single most important thing to know about reading U.S. labels, and the reason “no wheat” never equals “gluten-free.”

• GFCO certification — 10 ppm

  Third-party certification tests to a stricter 10 ppm standard and audits facilities. We treat certification as a stronger signal than the FDA claim: it clears conditional ingredients like oats that a bare label claim does not.

The review process

1. Every lexicon entry carries a written rationale and a citation to the FDA, a celiac organization, or peer-reviewed guidance — no entry ships without one.
2. The lexicon is versioned. Every verdict displays the exact lexicon version that produced it.
3. Katie Wilson, RN — founder of Lets Go Gluten Free — reviews every lexicon entry, verdict rule, and the copy on this page before launch and at every release.
4. A 50-product hand-graded test gate runs on every change. The hard rule: zero products that contain gluten may ever scan as GLUTEN-FREE. A red gate blocks release.
5. When an ingredient isn’t in the lexicon, a conservative AI classifier may assist — but AI-assisted scans are capped at “LIKELY — VERIFY” and never marked fully gluten-free.