Parent-Reported Barriers and Facilitators to Early and Sustained Feeding of Allergenic Foods: A Mixed-Methods Systematic Review

BACKGROUND: For the primary prevention of food allergies, several national professional organizations recommend introducing commonly allergenic foods, particularly peanut and egg, to infants at about age 4 to 6 months (or when developmentally appropriate) and continuing regular feeding to maintain tolerance. However, parents often face challenges with introduction and/or sustained feeding. OBJECTIVE: To examine parent-reported barriers and facilitators to the early introduction and sustained feeding of commonly allergenic foods (peanut, egg, cow's milk, tree nuts, wheat, sesame, fish, shellfish, and soy) in infants. METHODS: MEDLINE, Embase, CENTRAL, CINAHL, and PsycInfo databases were searched for relevant articles published between January 2008 and July 2024. Extracted data from selected studies were synthesized using the Joanna Briggs Institute convergent integrated approach and analyzed using a reflexive thematic synthesis approach. RESULTS: We identified 9 studies reporting on the experiences of 4898 parents. More barriers than facilitators were identified. Five main themes related to barriers in introducing and feeding commonly allergenic foods to infants were identified: (1) perceived risk and fear of adverse reactions, (2) practical and lifestyle constraints, (3) infant-related feeding difficulties, (4) health care provider access and guidance, and (5) parental skepticism. One main theme related to facilitators was identified, namely, educational and health care supports. CONCLUSIONS: Parental, infant, and system-level barriers continue to limit adherence to guidelines for early and sustained feeding of commonly allergenic foods. Support from health care providers and accessible, practical guidance may help address these challenges. Future research is warranted to better understand facilitators of early and sustained allergen feeding across sociocultural contexts.