‘May contain gluten’ explained

Food-label warnings like ‘may contain gluten’ can be tricky to interpret. If you have coeliac disease or are sensitive to gluten, chances are you’ll be a little confused about this type of labelling. 

What does ‘may contain gluten’ mean?

Statements such as  ‘may contain…’, ‘may contain traces of…’ or ‘processed on equipment also used for…’ are different ways of indicating a potential risk of gluten cross-contact. This risk can occur at any stage of production — during growing, harvesting, storage, transport, or manufacturing — either in the finished product itself or in one of its ingredients.

What doesn’t it mean?

Precautionary statements do not mean gluten is present at a detectable level (more than 3 parts per million). To visualise this, imagine 3 crumbs of gluten in a million gluten-free crumbs. Under Food Standards Australia New Zealand law, it is illegal to include a ‘may contain’ warning on a food that contains detectable gluten. It is also illegal to use a precautionary statement on a product that is labelled ‘gluten free’.

Even when a precautionary statement is used, manufacturers must have strict processes and procedures in place to minimise gluten cross-contact. Any unintended gluten must be kept at the lowest practicable level, remain below 3 ppm, and be effectively controlled.

‘May contain gluten’ statements aren’t regulated

Precautionary warning statements are voluntary, so manufacturers choose whether put them on their products. Therefore, it’s impossible to tell whether foods without a statement have a lower risk of gluten cross-contact than those with a statement. The majority of foods without a ‘gluten free’ claim are made in a facility that also handles gluten. In most cases, it’s possible that a tiny trace of gluten could have entered the food i.e. it ‘may contain’ gluten. 

We’re well protected

In New Zealand and Australia, food manufacturers must declare gluten when it’s present at levels above 3ppm. In England, America and most of Europe, the threshold is higher — 20 ppm. This means the maximum amount of gluten that could legally be present in a food with a precautionary statement is lower here than in many other countries. As a result, people following a gluten-free diet in New Zealand and Australia are well protected.

Eating out and at home

Any food prepared in a restaurant or café that also handles gluten-containing ingredients is, in effect, a ‘may contain gluten’ food. The same applies to meals cooked in a home kitchen where gluten is present. In fact, the risk of gluten cross-contact when eating out is often higher than with packaged foods, where strict manufacturing controls and testing apply.

If you want to feel more confident eating away from home, my online guide ‘How to Eat Out as a Coeliac’ walks you through exactly how to minimise cross-contact risk, ask the right questions, and make safer choices. 

How much gluten makes someone with coeliac disease sick?

A 2019 review (35 studies) of coeliac disease research found that although the amount of tolerable gluten varies among people with coeliac disease, a daily gluten intake of <10mg is unlikely to cause gut damage¹. Let’s explore that further:

• 3ppm is the highest amount of gluten permitted in foods with a ‘may contain gluten’ warning. 3ppm equals 0.003 milligrams of gluten per gram of the food.
• If you ate 100g of crackers and they had exactly 3ppm of gluten in them, that would mean you’d eaten 0.3mg of gluten.
• To reach 10mg of gluten, you’d need to eat around 3,300g of a food that contained 3ppm of gluten. That’s quite a lot. 
• If you eat a very large amount of ‘may contain’ foods in one day, it’s possible to exceed the limit that may cause gut damage.
• If you eat a small to moderate amount of ‘may contain’ foods, you’re unlikely to.

Coeliac society advice

Coeliac Australia has this to say: “Research into the use of precautionary (‘may contain’-type) statements in Australia has shown that manufacturers tend to overuse rather than underuse them. Part of what we do involves working with manufacturers where we can to minimise the unnecessary use of precautionary labelling to maximise food choices without compromising food safety”. Coeliac Australia recommends that those with coeliac disease avoid eating food with precautionary warning statements relating to gluten².

Coeliac New Zealand does not recommend automatically avoiding foods with precautionary statements, as this could unnecessarily restrict your choice of foods. Instead, they advise taking a cautious, informed approach³.

What does this mean for you?

My take on eating foods with precautionary gluten warnings:

• Eating small amounts of “may contain” foods is unlikely to cause gut damage.
• The more ‘may contain’ foods you eat in one day, the higher the chances are that you’ll exceed the daily limit that may cause gut damage. Eating plenty of unprocessed foods i.e. fruit, vegetables, plain meat, eggs, milk, etc will reduce your risk.
• You don’t need to limit yourself to foods labelled ‘gluten free’. Doing so can be unnecessarily restrictive and expensive.
• Gluten-free foods that are not labelled as such, and that don’t carry a “may contain” warning, are very unlikely to harm you. If you’re unsure how to identify these foods safely, my online guide ‘Is it gluten free?’ will help. 
• Use your symptoms to guide you. If you notice that a specific ‘may contain’ product isn’t agreeing with you, swap it out for something else and carry on.
• If you’re coeliac, get your blood antibody levels tested annually. This helps check that gluten isn’t sneaking into your diet. If your results are normal and you feel well, keep doing what’s working for you!

 

Need personalised nutrition advice?
Elly McKenzie is a New Zealand-based nutritionist specialising in practical, evidence-based support for gut health, coeliac disease, irritable bowel syndrome, food allergies/intolerances, and general nutrition (including healthy eating, high cholesterol/blood pressure and pre-diabetes).

Consultations are available in person at her Mount Maunganui clinic (Tauranga) or across Aotearoa via secure Telehealth. Book a consultation or get in touch to learn more.

 

References

1. Al-Toma A, Volta U, Auricchio R, Castillejo G, Sanders DS, Cellier C, Mulder CJ, Lundin KEA. European Society for the Study of Coeliac Disease (ESsCD) guideline for coeliac disease and other gluten-related disorders. United European Gastroenterol J. 2019 Jun;7(5):583-613. doi: 10.1177/2050640619844125. Epub 2019 Apr 13. PMID: 31210940; PMCID: PMC6545713.
2. Coeliac Australia 2021.
3. Coeliac New Zealand Website 2021.