Primary dietary prevention of food allergy.

Objective: To present research and clinical evidence on the use of primary dietary prevention in food allergy management.

Data Sources: We conducted MEDLINE searches for pertinent articles published between January 1986 and October 2001 with use of the following keywords or phrases: prevention and diet and allergy, food allergy and prevention, and dietary prevention and food allergy or allergens. Also included are information and commentary reflecting the authors' cumulative clinical experience in an allergy unit of a city hospital.

Results: We define as "proactive" those strategies centered on "success factors," such as the early postnatal environment, prolonged breast-feeding, and use of formula and probiotic supplementation, in contrast to earlier "prohibitionist" approaches to prevention of food allergy. These two approaches are not antagonistic and may even be synergistic. We introduce this distinction in light of epidemiologic evidence and out of concern about compliance and the quality of life for patients.

Conclusions: Inasmuch as nutritional and immune maturation are implicated, the prohibitionist measures that are most effective in primary prevention of food allergy are exclusive breast-feeding for at least 6 months (for lifelong immunity and other benefits), delayed (after the sixth month) introduction of solid foods, and on-indication use of "hypoallergenic" formulas. Whether proactive strategies can be contemplated remains a debatable issue. Evidence for and against the scientific use of probiotics as well as microbiologic, epidemiologic, and clinical data are discussed. Review of published epidemiologic studies and randomized clinical trials is essential before planning dietary intervention or prevention.