A majority of children with IgE-mediated food allergies did not report reaction to foods with precautionary allergen labeling (PAL), according to new findings, and those who did had mild reactions which could indicate management possibilities for ingestion of PAL-containing foods in some with allergies.¹

These findings resulted from research conducted to address the confusion presented by PAL statements on food product packaging such as the phrase “may contain,” a statement known to be ignored by as many as 40% of those with allergies.^2,3

Given the limited amount of real-life data on the risks of PAL food introduction in communities, this research was conducted by its investigators and it was authored by François Graham, MD, MSc, from the Department of Allergy and Immunology at the Centre Hospitalier de l'Université de Montréal in Canada.

“The aim of our study was to assess the real-life risk of reacting to foods with PAL in children with IgE-mediated food allergy regularly ingesting these foods,” Graham and colleagues wrote.

Background and Findings

The investigators, in the period between 2018 - 2021, recruited children with clinician-confirmed food allergies from the pediatric allergy unit of the Geneva University Hospitals. In order to be eligible, the study participants had to be between 2 - 18 years old, have confirmed IgE-mediated allergies to at least a single food such as tree nuts, peanut, sesame, wheat, soy, egg, or milk, and regularly consume foods with PALs.

Among the most common food allergy diagnoses, the research team found the following:

• Peanut allergy was most frequently diagnosed at 58%
• Cashew was second most at 52%
• Hazelnut was third at 42%
• 76% of study participants repored multiple food allergies and had a median number of 3

Overall, the team ended up with a total of 100 participants in their study and found that the median age at the time of their survey was shown to be 6 years old, and participants had been found to be living with these allergies to certain foods for a median of 4.3 years.

At diagnosis, 75 oral food challenges (OFCs) were done on 60 participants, and all OFCs were found to have positive results and a median reaction severity grade of 2 according to the Sampson scale of 1 - 4.

The investigators noted the median cumulative reactive dose (CRD) for the combined number of allergens was shown to be 430 mg of protein. Additionally, they reported that a substantial 57% of children consumed food products with PALs 2 - 5 times per week and 28% consumed such foods each day.

The team reported that the majority of reactions to food products with PALs were shown to be mild and occurred within 10 minutes after consuming the food. The majority of those in the study were found to have not reported any reaction to foods with PALs—at a rate of 82%—and for those who did, the reactions were shown to be both rare and mild.

The investigators noted that participants had a relatively high median reactivity threshold, which could help to explain their higher tolerance level to these types of foods. However, 1 in 5 of the participants did react to PAL foods on a minimum of 1 occasion in the past.

Additionally, the research team reported that food reaction risk with PALs was shown to be not affected by age, gender, food allergy type, or atopic background. They added that the median sIgE in the study was shown to be somewhat higher in reactors compared to those who did not react–with 6.92 kU/L versus 4.23 kU/L, respectively.

That being said, the difference was not shown to be statistically significant. The team also found that OFC CRD was shown to be somewhat lower in those who reacted compared to those who did not—419.5 mg of protein versus 535.5 mg of protein, respectively.

The investigators concluded that there is rising interest in alternatives to strict food allergen avoidance and the adoption of an individualized management tactic to PAL based upon reactivity thresholds.

“Future larger prospective studies from different centers including heterogeneous food allergy profiles and reactivity thresholds are needed to better characterize the real-world consumers' risk when faced with these products and to better identify the patients that can introduce them safely,” they wrote.

References

1. ^{Graham F, Benhamou AH, Liu YJ, Caubet JC, Eigenmann PA. Real-life evaluation of tolerance to foods with precautionary allergen labeling in children with IgE-mediated food allergy [published online ahead of print, 2023 Jul 26]. Allergy. 2023;10.1111/all.15821. doi:10.1111/all.15821.}
2. ^{Marchisotto MJ, Harada L, Kamdar O, et al. Food allergen labeling and purchasing habits in the United States and Canada. J Allergy Clin Immunol Pract. 2017;5(2):345-51 e2.}
3. ^{Blom WM, Michelsen-Huisman AD, van Os-Medendorp H, et al. Accidental food allergy reactions: products and undeclared ingre- dients. J Allergy Clin Immunol. 2018;142(3):865-875.}