Israeli Study Debunks a Common Fear About Food Allergies

Parents of children with food allergies frequently fear that accidental skin contact with allergenic foods may trigger a severe systemic allergic reaction. Findings from a recent Israeli study offer reassuring, evidence-based guidance that could help ease unnecessary anxiety.

A large multicenter Israeli study, led by Dr. Idit Lachover-Roth, Director of the Allergy and Clinical Immunology Unit at Rambam Health Care Campus, aimed to evaluate the risk of systemic allergic reactions following controlled skin exposure to common food allergens in children with confirmed food allergies (FA).

According to Dr. Lachover-Roth, the study was driven by a desire to better understand what actually triggers significant allergic reactions in children with FA. The study is one of the largest prospective studies of its kind to evaluate a broad range of allergenic foods under controlled conditions.

Dr. Lachover-Roth headed the research that was conducted at Meir Medical Center and Schneider Children's Medical Center, both operated by Clalit Health Services. A total of 293 children, aged 1–18 years, were recruited from the allergy clinics at the two medical centers: 192 (65.5%) with confirmed FA comprised the study group, while 101 (34.5%) served as the control group. Participants underwent patch testing in which the allergenic food: milk, peanuts, eggs, sesame, or tree nuts, was applied to the forearm for 15 minutes. A total of 465 patch tests were performed: 263 in the FA group and 202 in the control group.

The findings, recently published in the international journal Acta Paediatricas, were both consistent and reassuring. In 83.7% of exposures, no reaction occurred—not even at the site of contact. Approximately 15% of children developed only a mild localized skin reaction, such as redness or slight swelling at the contact site. Only three children (1.1%) developed a somewhat more extensive skin reaction limited to the tested arm, which resolved after treatment with an antihistamine. Most importantly, not a single child experienced anaphylaxis or any systemic allergic reaction.

Younger age was the strongest predictor of skin reactivity, with younger children more likely to develop a mild localized skin reaction. Children with milk allergies also had a slightly higher rate of localized reactions. Even in these cases, however, no episodes of anaphylaxis were observed.

"Many families live in a constant state of vigilance because they fear that even accidental skin contact with an allergenic food could lead to anaphylaxis," explains Dr. Lachover-Roth. "Although a few previous studies have examined the effects of skin exposure, the question has never been investigated on this scale. Our findings show that when allergenic food comes into contact with intact skin—even in children with confirmed food allergies—the risk of a serious reaction is extremely low, approaching zero. These results allow us to provide families with evidence-based guidance and help reduce fears that are not supported by scientific data."

The researchers emphasize that the study does not change current medical recommendations. Children with FA should continue to avoid eating foods to which they are allergic, carry an epinephrine auto-injector when prescribed, and prevent oral exposure. Furthermore, the study did not examine contact with broken skin or mucous membranes, where the risk may be different.

Dr. Idit Lachover-Roth with a patient - Photography: Rambam HCC

"The fear of accidental contact with allergenic foods often leads to persistent anxiety and significantly affects the quality of life of both children and their families," says Dr. Lachover-Roth. "Our findings demonstrate that accidental exposure of intact skin to allergenic foods carries a very low risk of a clinically significant reaction. As long as standard safety precautions are followed, families can reduce unnecessary anxiety about accidental skin contact with allergenic foods."