Food allergy: Is strict avoidance the only answer?

Abstract

It is an immunological paradigm that avoidance of food allergen may reduce the risk or prevent immunological reactions and conversely that a greater exposure increases the magnitude of the immune response. Consequently, food allergen avoidance has been recommended to reduce the risk of sensitization in infants and to prevent clinical reactions in children with positive skin prick tests (SPT). In the latter setting, it is hoped that avoidance may either promote or at least not retard the development of tolerance. Animal studies, however, have demonstrated that tolerance to food allergens may be induced by either large (high zone tolerance) or small (low zone tolerance) doses, whereas doses in between may actually stimulate immune responses. In this review, we discuss whether strict allergen avoidance is always the most appropriate strategy for preventing or managing IgE‐mediated food allergy.

Characteristics of childhood peanut allergy in the Australian Capital Territory, 1995 to 2007

“…Until the results of a controlled study comparing avoidance with early introduction of peanut on the risk of PA development are available (http://www.leapstudy.co.uk/index.html), it remains speculative whether public health measures to avoid or delay exposure to allergenic food [27][28][29][30] designed to prevent FA might (in part) have contributed to its recent rise. 24,25 …”

“…Other hypotheses that have recently been reviewed include the hygiene hypothesis, topical sensitization, cesarean section, antacid medication use by infants, food processing methods, vitamin D exposure, alterations in dietary fat consumption, and perhaps even delayed introduction of allergenic food. [22][23][24][25] The rapid increase in demand for FA assessment in Australia poses a public health issue that has already affected medical resources and waiting lists in the public and private sectors in Australia. 26 An increase in PA incidence will only serve to fuel that demand, is likely to result in a cohort effect for higher prevalence in older individuals (in whom anaphylaxis and mortality is more likely), and may require a reassessment of the relatively low risk of fatal outcomes in young children if the underlying problem is more common.…”

Avoidance or exposure to foods in prevention and treatment of food allergy?

“…However, the same proponents of the 'baked goods' regimen are the first to admit to the scientific press that they would think twice before allowing patients' requests in regard to the re-introduction or prophylactic introduction despite published evidence of the contrary [40]. As far as the avoidance side of the argument is concerned, however, although we are willing to agree that 'the change from a milk avoidance diet to a milk-limited diet could provide a substantial improvement to the quality of life of milk-allergic individuals' [41 ], we tend to regard as interesting but as hitherto speculative that 'the frequency of prolonged or permanent milk allergy may be reduced if this type of diet can augment the development of tolerance' [42 ].…”

“…Such studies have been interpreted as not lending support to the proposal that continued exposure to allergen will increase immunoglobulin E levels or delay the acquisition of tolerance [42 ]. However, there are several objections to embracing this approach wholesale.…”

Effect of Heat-Killed Escherichia coli, Lipopolysaccharide, and Muramyl Dipeptide Treatments on the Immune Response Phenotype and Allergy in Neonatal Pigs Sensitized to the Egg White Protein Ovomucoid

“…Therefore, due to the complex nature of allergic disease, standard treatments are limited to allergen avoidance, nutritional support, and immediate access to emergency medication (38). Although many allergen-specific immunotherapies have been investigated (1,2,3,43), general, allergen-nonspecific treatments to control allergic predisposition and clinical allergy, regardless of the inciting allergen, would be of great benefit (1).…”