Medscape: Beyond the “Big 8”

[GoingNuts]

Beyond the 'Big Eight' Allergens: Foods Most Likely to Spur Symptoms
Marcia Frellick
 December 16, 2025
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Summarize This Article
A retrospective study of almost 200 foods that caused a possible food allergy and 45 foods that caused a probable food allergy in an outpatient allergy clinic yielded new insight on triggers beyond those typically associated with allergic reactions.


The study, published in The Journal of Clinical Allergy and Immunology, was led by Emily Kallen, MD, with the Department of Dermatology and Allergology at the University Medical Center Utrecht in Utrecht, Netherlands.

Studies typically have focused on the "Big Eight," the researchers noted — cow's milk, hen's egg, wheat, soy, peanut, tree nuts, fish, and shellfish. But this study assessed both possible and probable predictors for allergic reaction to a broad array of food groups and severity of reactions.

The study included 1085 patients, of whom 66.9% had a probable food allergy (patients reported symptoms with sensitization) and 33.1% had a possible food allergy (patients reported symptoms, independent of sensitization). Patients reported symptoms to 192 foods, and sufficient sensitization data were available for 45 foods, according to the report.


Adult patients who had symptoms within 2 hours of consuming any food between July 2018 and September 2023 were included retrospectively. Sensitization was measured by skin prick test and/or specific immunoglobulin E for the triggering food when possible.

30 Foods Cause 80% of Symptoms

Among the findings was that almost 80% of the reported symptoms were caused by 30 foods. "Fruit, tree nuts, and legumes most commonly caused an allergy, and insects, meat, and spices or herbs least commonly. Severe symptoms were most frequently reported for seeds or pits, nuts, and legumes."

Of patients who had a possible fruit allergy, apple allergy was most commonly reported (44.4%). "About a third of the patients reported symptoms to kiwi, hazelnut, walnut, or peanut; about a quarter to cherry; and a fifth to almond, peach, or pear," the authors wrote.


Among other findings:

The most common atopic comorbidity was allergic rhinitis, present in 85.9% of patients.
The average number of foods reported to cause a reaction within a patient was 5, with a maximum of 31.
Of all the foods reported to cause a reaction per patient, the most severe reaction was mild in 17.6% of cases, moderate in 40.8%, and severe in 41.6%.
Foods Causing Severe Reactions

In terms of severity, seeds and pits (39.8%) and fish (39.2%) were most likely to cause severe reactions, followed by legumes, nuts, and crustaceans (about a third of patients reported severe reactions).

But when looking at absolute numbers of patients, severe reactions were seen most frequently for nuts (n = 252), legumes (n = 218), and fruits (n = 149). "So, in absolute patient numbers, fruit belongs to one of the food groups most frequently causing severe reactions even though it is generally seen as a food causing mild symptoms," the authors wrote.


"We are seeing more symptoms around fruit," such as itching in the mouth or ears, in the US, allergist Payel Gupta, MD, from the Allergy and Asthma Network, told Medscape Medical News.

There are several reasons for that, she says, including the fact that fruits and vegetables share similar proteins with different types of pollen. "Pollen allergies in general are getting worse, secondary to climate change, and pollen seasons are getting longer. The more we're exposed to, the more possibility for our bodies to become sensitized, which can lead to allergy," Gupta said.

Limitations in Data

She cautions against additional concern about eating fruits and vegetables and other foods important to a healthy diet based on these findings. One important indicator of a food allergy is if patients are having the reaction every time they eat a certain food. "If it's sometimes, it's not a true food allergy. We want to be very, very careful before we tell someone they have a food allergy," Gupta said.

She pointed to limitations in the Kallen and colleagues study, including that it was retrospective and included just more than 1000 people in a single outpatient clinic. Additionally, she notes, Netherlands data are not broadly generalizable to a US population, which is more heterogeneous.


"If patients are complaining of a possible food allergy, the best thing to do is to refer to an allergist and not try to do the testing themselves," Gupta said. She says a message to nonallergist physicians is, "Definitely don't send large food allergy panels. Allergists never do those panels. They exist in the system, but really they shouldn't" because they produce false positives and lead to patient anxiety and food avoidance.

Kallen and Gupta reported having no relevant financial relationships.