Food Allergies

AAP Summary of IgE Test Characteristics and Limitations

Treatment decisions for infants and children with allergy should be made on the basis of the appropriate diagnosis and identification of causative allergens, which may be identified through directed specific IgE testing.
Allergy tests for specific IgE must be selected and interpreted in the context of a clinical presentation; test relevance may vary according to the patient’s age, allergen exposure, and performance characteristics of the test.
Positive specific IgE test results indicate sensitization, which is not equivalent to clinical allergy. Large panels of indiscriminately performed screening tests may, therefore, provide misleading information.
Tests for specific IgE may be influenced by cross-reactive proteins that may or may not have clinical relevance to disease.
Increasingly higher levels of specific IgE (higher concentrations on serum tests or skin prick test wheal size) generally correlate with an increased risk of clinical allergy.
Specific IgE test results typically do not reflect severity of allergies.
Tests for allergen-specific IgG antibodies are not helpful for diagnosing allergies.
Consultation with a board-certified allergist-immunologist should be considered, because test limitations often warrant additional evaluation to confirm the role of specific allergens.

AAP, American Academy of Pediatrics.

From American Academy of Pediatrics. Pediatric Nutrition. 9th ed. American Academy of Pediatrics; 2025.

Guidelines for Early Introduction of Peanut

Infant Clinical Criteria	Recommendations	Earliest Age of Peanut Introduction
Guideline 1: Severe eczema, egg allergy, or both	Strongly consider evaluation by serum IgE or skin prick testing, and if necessary, an oral food challenge. On the basis of test results, introduce infant-safe peanut-containing foods.	4-6 mo
Guideline 2: Mild to moderate eczema	Introduce infant-safe peanut-containing foods.	Around 6 mo
Guideline 3: No eczema or any food allergy	Introduce infant-safe peanut-containing foods.	Age appropriate and in accordance with family preferences and cultural practices

From American Academy of Pediatrics. Pediatric Nutrition. 9th ed. American Academy of Pediatrics; 2025.

AAP Recommendations for Food Allergy Prevention Through Diet

There is lack of evidence that maternal dietary allergen restrictions during pregnancy or lactation play a significant role in the prevention of food allergy.
There is no evidence that any duration of breastfeeding prevents or delays food allergy in infants and children.
There is no evidence that delaying the introduction of allergenic foods beyond 4 to 6 months prevents food allergy, including peanut, eggs, and fish.
There is evidence that the early introduction of infant-safe forms of peanut reduces the risk for peanut allergies. Data are less clear for the timing of introduction of egg.

AAP, American Academy of Pediatrics.

From American Academy of Pediatrics. Pediatric Nutrition. 9th ed. American Academy of Pediatrics; 2025.