Different countries have different rules regarding food allergy advisory labeling. The summary below applies to U.S.
The current law
In the U.S., the Food Allergen Labeling and Consumer Protection Act (FALCPA) of 2004 is a law requiring that the 8 major allergens or allergenic food groups — milk, egg, fish, crustacean shellfish, tree nuts, wheat, peanut, and soy — be declared on ingredient labels using plain English words. The FALCPA only applies to the 8 major allergens.
Food allergy management in 4 steps (click to enlarge the image).
Unclear advisory labels
Certain phrases are used by the food industry when a particular allergen is not an intended ingredient of the food, but rather may contact or become a part of the food despite accepted manufacturing processes. Various terms include: "may contain," "processed in a facility with," "manufactured on shared equipment with."
As of year 2014, these terms are applied entirely at the discretion of the manufacturer. There is no law that mandates such listing.
Unfortunately, such confusing labeling is common. An audit of 20,000 supermarket products found that 17% of the products had some form of advisory labeling. Numerous products have advisory labeling and ambiguities that present challenges to consumers with food allergy. Advisory warnings included "may contain" (38%), "shared equipment" (33%), and "within plant" (29%). Nonspecific terms, such as "natural flavors" and "spices," were found on 65% of products and were not linked to a specific ingredient for 83% of them. Additional ambiguities included unclear sources of soy (lecithin vs protein), nondisclosure of sources of gelatin and lecithin, and simultaneous disclosure of "contains" and "may contain" for the same allergen, among others.
Clearer additional allergen labeling regulation could improve safety and quality of life for individuals with food allergy. (Audit of manufactured products: use of allergen advisory labels and identification of labeling ambiguities. Pieretti MM, Chung D, Pacenza R, Slotkin T, Sicherer SH. Allergy Clin Immunol. 2009;124(2):337).
Advisory labeling can be both beneficial and detrimental to food-allergic individuals. The risk of allergen exposure is likely reduced, although if the terms are applied too broadly to food products that pose little risk, allergic consumers may chose to ignore the warnings in order to expand their dietary options.
What to do?
The general recommendation for patients is to avoid foods that include the culprit allergen in an advisory statement, because it is impossible for the consumer to determine the actual risk, and serious reactions from cross-contact have been reported.
A study examined products with milk advisory labeling (Risks associated with foods having advisory milk labeling. Crotty MP, Taylor SL. Allergy Clin Immunol. 2010;125(4):935). Detectable milk was found in 42% of these products, a much higher frequency than similar studies of peanut.
Audit of manufactured products: use of allergen advisory labels and identification of labeling ambiguities. Pieretti MM, Chung D, Pacenza R, Slotkin T, Sicherer SH. Allergy Clin Immunol. 2009;124(2):337
Risks associated with foods having advisory milk labeling. Crotty MP, Taylor SL. Allergy Clin Immunol. 2010;125(4):935
Management of food allergy: Avoidance. UpToDate, 2014. http://buff.ly/1hGvaXg
FDA: Food Allergen Labeling And Consumer Protection Act of 2004 Questions and Answers http://buff.ly/1mx6L7a
Comments from Twitter:
KFA Div of AAFA.org @kfatweets: A real conundrum for those of us who deal with this.