Although many parents report food allergy in their children and the incidence of parental report has increased over time,1,2 the actual incidence of confirmed food allergy is much lower.3,4 However, food allergy still is estimated to impact 2% to 10% of pediatric patients, and its prevention is an important goal in pediatric practice because there is no current cure.5,6
The pediatrician needs to be aware of changing practice recommendations related to the introduction of complementary foods for children. Although pediatricians who have been in practice for some time may have previously asked parents to delay the introduction of highly allergenic foods, emerging evidence now suggests just the opposite. Earlier introduction of highly allergenic foods may actually prevent food allergy.
Food allergy basics
WHAT IS FOOD ALLERGY?
Food allergies refer to reactions that occur as a result of immunologic reactions in response to certain foods. Food allergies are generally classified as either immunoglobulin (Ig)E mediated or non–IgE mediated and have different clinical presentations.7
WHAT ARE THE MOST COMMON FOOD ALLERGENS?
Whereas any food can theoretically lead to an allergic reaction, the most common offenders are:
· Cow’s milk
· Tree nuts
HOW DO FOOD ALLERGIES PRESENT?
Immunologic IgE-mediated reactions may present with the following symptoms:7
· Gastrointestinal anaphylaxis
· Generalized anaphylaxis
· Oral allergy syndrome
Non–IgE-mediated food allergies are more likely to present with subacute, chronic symptoms that are isolated to the gastrointestinal tract or skin.7
1. Peters RL, Koplin JJ, Gurrin LC, et al; HealthNuts Study. The prevalence of food allergy and other allergic diseases in early childhood in a population-based study: HealthNuts age 4-year follow-up. J Allergy Clin Immunol. 2017;140(1):145.e8-153.e8.
2. Verrill L, Bruns R, Luccioli S. Prevalence of self-reported food allergy in U.S. adults: 2001, 2006, and 2010. Allergy Asthma Proc. 2015;36(6):458-467.
3. Venter C, Pereira B, Grundy J, et al. Incidence of parentally reported and clinically diagnosed food hypersensitivity in the first year of life. J Allergy Clin Immunol. 2006;117(5):1118-1124.
4. Eggesbø M, Botten G, Halvorsen R, Magnus P. The prevalence of CMA/CMPI in young children: the validity of parentally perceived reactions in a population-based study. Allergy. 2001;56(5):393-402.
5. Chafen JJ, Newberry SJ, Riedl MA, et al. Diagnosing and managing common food allergies: a systematic review. JAMA. 2010;303(18):1848-1856.
6. Du Toit G, Sampson HA, Plaut M, Burks AW, Akdis CA, Lack G. Food allergy: update on prevention and tolerance. J Allergy Clin Immunol. 2018;141(1):30-40.
7. Burks AW, Tang M, Sicherer S, et al. ICON: food allergy. J Allergy Clin Immunol. 2012;129(4):906-920.
8. Committee on Nutrition; American Academy of Pediatrics. Hypoallergenic infant formulas. Pediatrics. 2000;106(2 pt 1):346-349.
9. Greer FR, Sicherer SH, Burks AW, American Academy of Pediatrics Committee on Nutrition; American Academy of Pediatrics Section on Allergy and Immunology. Effects of early nutritional interventions on the development of atopic disease in infants and children: the role of maternal dietary restriction, breastfeeding, timing of introduction of complementary foods, and hydrolyzed formulas. Pediatrics. 2008;121(1):183-191.
10. Greer FR, Sicherer SH, Burks AW; Committee on Nutrition, Section on Allergy and Immunology. The effects of early nutritional interventions on the development of atopic disease in infants and children: the role of maternal dietary restriction, breastfeeding, hydrolyzed formulas, and timing of introduction of allergenic complementary foods. Pediatrics. 2019;143(4):e20190281.
11. Du Toit G, Roberts G, Sayre PH, et al; LEAP Study Team. Randomized trial of peanut consumption in infants at risk for peanut allergy. N Engl J Med. 2015;372(9):803-813. Erratum in: Randomized trial of peanut consumption in infants at risk for peanut allergy. N Engl J Med. 2016)
12. Du Toit G, Sayre PH, Roberts G, et al; Immune Tolerance Network LEAP-On Study Team. Effect of avoidance on peanut allergy after early peanut consumption. N Engl J Med. 2016;374(15):1435-1443.
13. Perkin MR, Logan K, Tseng A, et al; EAT Study Team. Randomized trial of introduction of allergenic foods in breast-fed infants. N Engl J Med. 2016;374(18):1733-1743.
14. Ierodiakonou D, Garcia-Larsen V, Logan A, et al. Timing of allergenic food introduction to the infant diet and risk of allergic or autoimmune disease: a systematic review and meta-analysis. JAMA. 2016;316(11):1181-1192.
15. Togias A, Cooper SF, Acebal ML, et al. Addendum guidelines for the prevention of peanut allergy in the United States: summary of the National Institute of Allergy and Infectious Diseases-sponsored expert panel. Pediatr Dermatol. 2017;34(1):5-12.
16. Palmer DJ, Metcalfe J, Makrides M, et al. Early regular egg exposure in infants with eczema: a randomized controlled trial. J Allergy Clin Immunol. 2013;132(2):387.e1-392.e1.
17. Bellach J, Schwarz V, Ahrens B, et al. Randomized placebo-controlled trial of hen’s egg consumption for primary prevention in infants. J Allergy Clin Immunol. 2017;139(5):1591.e2-1599.e2.
18. Palmer DJ, Sullivan TR, Gold MS, Prescott SL, Makrides M. Randomized controlled trial of early regular egg intake to prevent egg allergy. J Allergy Clin Immunol. 2017;139(5):1600.e2-1607.e2.
19. Wei-Liang Tan J, Valerio C, Barnes EH, et al; Beating Egg Allergy Trial (BEAT) Study Group. A randomized trial of egg introduction from 4 months of age in infants at risk for egg allergy. J Allergy Clin Immunol. 2017;139(5):1621. e8-1628.e8.
20. Natsume O, Kabashima S, Nakazato J, et al; PETIT Study Team. Two-step egg introduction for prevention of egg allergy in high-risk infants with eczema (PETIT): a randomised, double-blind, placebo-controlled trial. Lancet. 2017;389(10066):276-286.
21. Perkin MR, Bahnson HT, Logan K, et al. Association of early introduction of solids with infant sleep: a secondary analysis of a randomized clinical trial. JAMA Pediatr. 2018;172(8):e180739.
22. Fleischer DM, Spergel JM, Assa’ad AH, Pongracic JA. Primary prevention of allergic disease through nutritional interventions. J Allergy Clin Immunol Pract. 2013;1(1):29-36.
23. Section on Breastfeeding. Breastfeeding and the use of human milk. Pediatrics. 2012;129(3):e827-e841.