After immunotherapy, Asian foods might be safe for peanut-allergic people

People who are allergic to peanut are strongly advised to avoid Asian style foods due to the perceived high risks of peanut being present. A new study has sought to quantify the levels of peanut that may be introduced through sharing kitchen materials in an Asian restaurant setting. Comparing these levels with various improvements in an individual’s peanut tolerance, such as through immunotherapy, highlights potentially life-saving impacts.

Researchers created three versions of popular peanut-containing sauces and used these to represent common ingredients used in Asian restaurant kitchens. Different combinations of utensils, equipment, sauces and test conditions were prepared by a professional chef, with or without cleaning procedures that would represent common and normal daily practice.

Residual amounts of peanut-containing material on kitchen equipment and utensils were measured and used for quantitative risk assessment to model the risk reduction associated with building up an individual’s tolerance to peanut through a treatment such as immunotherapy.

Without being cleaned, samples taken from shared utensils had 23 to 1519 mg peanut protein. After a water rinse, 3 to 82 mg peanut protein was detected. Shared woks and pans had up to 20 mg peanut protein after rinsing.

If, through an immunotherapy treatment program, someone can achieve a tolerance threshold of 300 mg peanut protein, modelling showed that brief cleaning would reduce the predicted relative risk by 94.9 to more than 99.99 per cent. For someone with an initial tolerance of less than or equal to 100 mg peanut protein who can reach a threshold of 300 mg peanut protein, this would reduce the relative risk of an allergic reaction by 63.5 to 91.1 per cent – even when kitchen equipment was shared and not cleaned. This risk reduction could increase to 91.0 to 99.7 per cent if a person can reach a tolerance threshold of 1000 mg peanut protein.

Immunotherapy treatments that can boost a person’s tolerance threshold to achieve an eliciting dose of 300 or 1000 mg peanut protein are likely to prevent potentially life-threatening allergic reactions in peanut-allergic people who accidentally consume peanuts due to suboptimal restaurant kitchen practices.

Reference: Remington et al. 2020 Annals of Allergy, Asthma and Immunology. DOI: 10.1016/j.anai.2020.07.030.

Allergen Bureau note: Author Ben Remington is a member of the VITAL Scientific Expert Panel. See VITAL Science.