Gluten-Free Symbols on Food

The Crossed Grain mark, the schemes behind it, and the parts-per-million threshold each one sets. Also the difference between a licensed mark and a manufacturer printing gluten free on its own packaging, which is not the same guarantee.

The Crossed Grain

An ear of wheat inside a circle with a bar struck through it. It is a registered trademark of the Association of European Coeliac Societies, licensed country by country through national member societies. Coeliac UK licenses it in the United Kingdom. A licensee is audited and pays for the license, and many packs print a license code under the mark, which is the part that makes it checkable rather than decorative.

The thresholds, which are not all the same

Scheme	Threshold for a gluten-free claim	Set by
Codex Alimentarius	Not more than 20 mg/kg, that is 20 parts per million	The Codex standard for foods for special dietary use for people intolerant to gluten
European Union	20 ppm or below for gluten-free; 100 ppm or below for very low gluten, which applies only to specially processed cereal ingredients	Regulation (EU) No 828/2014
United States	Less than 20 ppm	The FDA gluten-free labeling rule. The claim is voluntary, but making it obliges you to meet the rule
GFCO (a circled GF)	10 ppm	The Gluten-Free Certification Organization, a program of the Gluten Intolerance Group

Twenty ppm is the common floor because most regulators followed the Codex figure. A mark set at 10 ppm is stricter than the law requires, which is the whole reason some brands pay for it.

A printed claim is not a certification mark

The words gluten free typed onto a pack by the manufacturer are a regulated claim in the EU, the UK and the US, and the product must meet the threshold. What is missing is the third party. A licensed mark adds an outside audit of the process, not just the finished number. Both are stronger than the category below.

May contain, and made in a facility

Precautionary allergen labeling is voluntary. There is no threshold behind it, no audit, and no consistent wording. May contain gluten, not suitable for, and made in a facility that also handles wheat are the manufacturer’s own risk statement. Just as importantly, the absence of that wording does not prove the absence of cross-contact, because nobody is obliged to add it. Most people with celiac disease treat any of these phrases as a reason to put the pack down.

Oats

Oats do not contain gluten, but they are routinely contaminated in the field, in transport and at the mill, which is why gluten-free oats are grown and handled on a separate chain. Some people with celiac disease also react to avenin, the oat protein itself. That is why a certified product can carry the Crossed Grain and still print contains oats, and why some schemes exclude oats from certification entirely.

Food allergy symbols, since gluten sits inside the wider allergen declaration rules
Food brand symbols for the other certification marks that share the label
Food symbols for the full map of what is printed on a package