Food labelling is one of the most important tools that people with coeliac disease rely on every single day. A recent development in the way the presence of gluten is assessed and communicated on food packaging represents a significant step forward for food safety. In November 2025, the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) agreed a new scientific reference point for gluten in precautionary allergen labelling, and in July 2026 this was adopted into international guidance by the Codex Alimentarius Commission. This article explains what has changed, the science and background behind it, and what it means in practice for people following a gluten-free diet and for the food industry.

Coeliac disease is a chronic, immune-mediated (non-IgE) condition that occurs in genetically predisposed people when they are exposed to gluten proteins from wheat , rye, barley and contaminated oats. Sustained gluten ingestion causes damage to the lining of the small intestine and is associated with a range of adverse health outcomes, including nutrient malabsorption, osteoporosis and other systemic complications. A strict, lifelong gluten-free diet is currently the only treatment.

Crucially, coeliac disease is fundamentally different from an IgE-mediated food allergy. An IgE allergy (such as a wheat allergy) can cause an acute reaction after a single exposure, so allergen thresholds have historically been built around protecting against one-off exposures. Coeliac disease, by contrast, is driven by chronic, cumulative exposure - the total amount of gluten consumed over time. This distinction is central to understanding the new guidance.

Two different labelling questions currently sit side by side on packaging:

1. “Gluten-free” claims - a deliberate, verified claim that a product is safe for people with coeliac disease.
2. Precautionary allergen labelling (PAL) - voluntary “may contain gluten” statements used when there is a risk of unintended gluten presence, for example through cross-contact during manufacturing.

Until now there has been no agreed scientific basis for when a “may contain gluten” statement is genuinely warranted. This has led to inconsistent, overly cautious and sometimes vague statements (such as “made in a factory that also handles wheat”), which can unnecessarily restrict the choices available to people with coeliac disease and erode trust in labelling.

The experts modelled chronic (cumulative) daily gluten exposure rather than single exposures. Their overriding aim was to ensure that a person’s total daily gluten intake does not exceed 10 mg per day, the level below which the risk of harm to people with coeliac disease is considered acceptably low.

Modelling tested a range of possible reference doses (from 1 mg up to 10 mg of gluten), taking into account how often cross-contact occurs, the concentration of gluten when it is present, and how much of different foods people eat across multiple eating occasions. The analysis found that reference doses of 5-10 mg would not push median daily intake above the 10 mg ceiling. The experts then chose a conservative 4 mg reference dose to provide an additional margin of safety. Importantly, this replaces the previous approach based on 5 mg of total wheat protein, and for the first time is specific to gluten and to coeliac disease rather than borrowed from wheat-allergy science.

From reference dose to a real-world “action level”

The 4 mg reference dose is not applied directly to a label. Instead it is used to calculate a food-specific action level - a concentration threshold that depends on how much of that particular food a person would typically eat in one eating occasion. If a risk assessment shows that unintended gluten cannot be prevented or reduced below the action level, a “may contain gluten” statement should be applied. If it can, the precautionary statement is not needed.

A scientific recommendation only becomes influential once it is taken up by risk managers. At the 49th Session of the Codex Alimentarius Commission (July 2026), updated guidance on precautionary allergen labelling was adopted that, for the first time, includes a reference dose for cereals containing gluten. This means gluten cross-contact should now be evaluated using science specific to coeliac disease - accounting for combined exposure from wheat, barley, rye and related grains, and for the long-term cumulative risk unique to the condition.

Codex standards are not automatically law in any single country, but they are highly influential and often shape national and regional regulation over time. The direction of travel is towards more consistent, meaningful and risk-based labelling worldwide.

Codex standards are not automatically UK law, and the changes are being introduced mainly through updated guidance rather than new legislation, so consumers will not see labels change overnight. In the UK, this work is led by the Food Standards Agency (FSA). The FSA has indicated it intends to align the UK with the updated Codex precautionary allergen labelling standard, however further discussion and agreement on this is required before any timelines can be set. Visible changes on food labels will be introduced progressively over the coming years.

1. Greater scientific accuracy: Labelling decisions are now based on data reflecting long-term, cumulative exposure rather than assumptions carried over from IgE allergy models.
2. Better protection for people with coeliac disease: The approach is explicitly designed to keep cumulative daily intake below the 10 mg gluten threshold associated with harm.
3. Clearer, more trustworthy labelling: A consistent, risk-based trigger for “may contain” statements should reduce vague or unnecessary warnings and rebuild consumer confidence.
4. More choice: By removing precautionary statements where the risk is genuinely negligible, more products can be confidently included in a gluten-free diet.

The introduction of a coeliac-specific, science-based reference dose for precautionary labelling is a meaningful advance. It brings:

• Greater transparency in food products.
• Better risk management for people with coeliac disease.
• A reduction in unintentional gluten exposure - and in unnecessary, confusing warnings.

Clearer, risk-based labelling is central to safe and informed eating. For people with coeliac disease, the reassuring message is that the gluten-free diet and the 20 ppm standard remain unchanged; what is improving is the accuracy and usefulness of the information on the pack - supported by a shift towards consistent, evidence-based labelling across the food industry.