This article is about “may contains” in the United States. For the Canadian version, click here .
Walk down any aisle at the supermarket and you’ll be greeted with labels of warning: “May contain peanuts”, “This product was produced in a facility that also has wheat”, and “Made on equipment that also processes milk” are just some examples.
Advisory labels or “may contains” (also called precautionary warnings) alert customers that traces of an allergenic food might unintentionally have wound up in a packaged food.
This inadvertent cross-contact can occur because of shared processing lines or baking equipment, or because workers use the same gloves while producing a number of products.
While advisory labels can be helpful to allergic consumers, they are voluntary and are not required under labeling regulations in United States.
What you need to know about “may contains” labels:
– The wording of the warning label does not give an indication as to the risk of the allergen being present. Allergists generally advise avoiding foods with advisory labels containing your allergen.
– The Food and Drug Administration states that advisory labels “should not be used as a substitute for adhering to current good manufacturing practices and must be truthful and not misleading.”
– Because advisory labels are voluntary, there is no guarantee products without these warnings will not contain traces of allergens. If you are ever unsure about a packaged food, Allergic Living suggests calling the manufacturer to find out about its food allergy management practices. If company representatives can’t adequately answer your questions, avoid the food.
– Food manufacturers that develop products with allergy concerns in mind are invaluable to consumers with food allergies. Become familiar with them (e.g. you will read about many in Allergic Living magazine). Some will promote right on a label that they produce in a “dedicated facility” without certain allergens – e.g. peanut or milk or wheat.
Extra Caution: If your child is peanut-allergic and a product has a precautionary warning for nuts but not peanuts, you would be wise to contact the manufacturer to ensure it isn’t including peanuts in the term “nuts”. (While peanuts are technically legumes, the term “nuts” can often gets used as a catchall.)
Do ‘May Contains’ actually contain the allergen – or is this just a case of companies protecting themselves against litigation?
While it may be that some companies simply add a “may contain” for legal protection, you can’t assume that is so. In at least three studies now, foods with precautionary labels did contain the allergen in question.
See our article Advisory Labels: May Contain Confusion  about a 2013 study in which products with “may contain” warnings were tested for the presence of peanut allergen.
See also: How to Read a Label When You Have Food Allergies