Objective:

To review the available evidence on the early introduction of allergenic foods and the possible protection in the development of food allergy in later stages.

Methods:

An exploratory review of randomized clinical trials whose study population included infants less than 6 months of age at enrollment with or without a diagnosis of food allergy was conducted. For the purposes of this review, eggs, peanuts, and wheat were included as potentially allergenic foods. The following databases were consulted: Medline, EBSCO, OVID, Science Direct and JSTOR (Journal Storage), Scielo, LILACS, Redalyc and Imbiomed from August to December 2021.

Results:

429 articles were identified, 412 were excluded, and the final analysis included 9 studies that met the inclusion criteria. Six trials correspond to allergy to eggs, two to peanuts and one to wheat. The age of introduction differs in all trials. The earliest exposure was at 3.5 months and the latest at 5.5 months. The reduction in the risk of developing food allergy occurred in children at risk of allergy. Adverse reactions were common, particularly with the introduction of egg.

Conclusions:

We found no evidence that early introduction (< 6 months of age) of allergenic foods reduces the risk of developing food allergy in infants without risk factors.