Q: What is the link between food allergies and eczema (atopic dermatitis), especially in young children? How is it determined if a food allergen is contributing to eczema?

Allison Ramsey, MD: Eczema, or atopic dermatitis, is a common rash that presents early in infancy and it’s closely associated with food allergies. We know infants and toddler with eczema have a much higher rate of sensitization, meaning a positive skin test or positive blood work to food.

Up to 30% of eczema patients will develop an immediate reaction to a food, meaning when they’re exposed to the food allergen, they will develop symptoms such as hives, itching, respiratory symptoms and/or gastrointestinal symptoms. The foods that cause skin reactions are the most common food allergens, including milk, egg, soy, peanut, tree nuts, wheat, fish and shellfish, and sesame.

Board-certified allergists are able to perform skin testing, blood tests or oral food challenges to determine whether a food is linked with eczema symptoms.

Sometimes food allergens can contribute to poor eczema control over time, especially in severe cases. For example, if a child consumes milk every day and milk is an allergen, this can lead to poor eczema control.

Allergists tend to err on the side of keeping the diet broad, but when chronic exposure to a specific food allergen leads to poor eczema control, sometimes eliminating that food from the diet can lead to skin improvement.

Food allergy and eczema are closely related and it is helpful to have an allergist involved in care to make sure patients treat their eczema effectively and follow an optimal diet.

Allison Ramsey, MD, FACAAI, is a board-certified allergist and immunologist in Greece, New York and is affiliated with Rochester Regional Health. She is a Fellow of the American College of Allergy, Asthma and Immunology (ACAAI).

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