Although accounts of food allergy date back to at least 400 BCE,1 significant concern in the medical literature can be traced back to the late 1980s. In May 1990, the British Medical Journal (BMJ) published a report of 4 deaths due to peanut allergy, noting, “All 4 were aware of their allergies, but could not avoid the allergen.”2 In 1992, Pediatric Annals stated that the most worrisome food allergy problem for pediatricians was peanut allergy because peanut appeared to be the most dangerous of the allergenic foods.3
Practicing physicians were anxious to offer parents a way to reduce their infants’ risk of developing food allergy and researchers were anxious to provide guidance. With a lack of robust evidence, they would have done well to follow the dictum, “Don’t just do something, stand there,” but that is not what occurred. In August 2000, the American Academy of Pediatrics (AAP) Committee on Nutrition established infant feeding guidelines that it described as reasonable, although it was acknowledged that there were no conclusive studies on which to base definitive recommendations.4 The guidelines stated “Solid foods should not be introduced into the diet of high-risk infants until 6 months of age, with dairy products delayed until 1 year, eggs until 2 years, and peanuts, nuts, and fish until 3 years of age.” Despite the lack of supporting evidence, by the late 1990s this advice had become gospel.
Although it may still feel somewhat surprising that guidelines were promulgated without good evidence, it is worth remembering that the concept of evidence-based medicine was not yet firmly established, the term only having been introduced in the 1990s.5,6
Concurrent with the new feeding guidelines, the prevalence of food allergy increased, and it became clear that the strategy of withholding these foods from infants to reduce the risk of developing food allergy had failed. In January 2008, an AAP Clinical Report acknowledged that there was no support for restricting the diet of infants beyond 4 to 6 months of age as a way to protect against the development of allergic disease such as eczema, asthma, or food allergy.7
New insight into peanut allergy
In November 2008, Gideon Lack, MD, and George Du Toit, MD, published a paper noting that despite guidelines recommending avoidance of peanut during infancy in the United States, United Kingdom, and Australia, peanut allergy had increased in these countries.8 They observed in particular that peanut allergy (PA) prevalence appeared to be much lower in Israel, where infants freely ate a peanut-containing snack during infancy. Their study confirmed not only their observation, but also that it was difficult to attribute this to something other than the early introduction of peanut to infants. (The study controlled for other factors, such as differences in social class, genetic background, and the particular variety of peanuts consumed.)
Lack and Du Toit concluded: “These findings raise the question of whether early introduction of peanut during infancy, rather than avoidance, will prevent the development of PA.” To answer this question, they conducted the Learning Early About Peanut (LEAP) study, which demonstrated unequivocally that infants at high risk of developing peanut allergy who ate peanut early and continuously had an at least 80% lower risk of developing peanut allergy than high-risk infants for whom the introduction of peanut was intentionally delayed.9
1. Sampson HA. Food allergy: past, present and future. Allergol Int. 2016;65(4):363-369.
2. Donovan K, Peters J. Vegetable burger allergy: all was nut as it appeared. BMJ. 1990;300(6736):1378.
3. Waggoner M. Parsing the peanut panic: the social life of a contested food allergy epidemic. Soc Sci Med. 2013;90:49-55.
4. American Academy of Pediatrics. Committee on Nutrition. Hypoallergenic infant formulas. Pediatrics. 2000;106(2 pt 1);346-349.
5. Claridge JA, Fabian TC. History and development of evidence-based medicine. World J Surg. 2005;29(5):547-553.
6. Sur RL, Dahm P. History of evidence-based medicine. Indian J Urol. 2011;27(4):487-489.
7. Greer FR, Sicherer SH, Burks AW; American Academy of Pediatrics Committee on Nutrition; American Academy of Pediatrics 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, timing of introduction of complementary foods, and hydrolyzed formulas. Pediatrics. 2008;121(1):183-191.
8. Du Toit G, Katz Y, Sasieni P, et al. Lack early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy. J Allergy Clin Immunol. 2008;122(5):984-991.
9. Du Toit G, Roberts G, Sayre, 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.
10. Poole JA, Barriga K, Leung DY, et al. Timing of initial exposure to cereal grains and the risk of wheat allergy. Pediatrics. 2006;117(6):2175-2182.
11. Prescott SL, Smith P, Tang M, et al. The importance of early complementary feeding in the development of oral tolerance: concerns and controversies. Pediatr Allergy Immunol. 2008;19(5):375-380.
12. Wennergren G. What if it is the other way around? Early introduction of peanut and fish seems to be better than avoidance. Acta Paediatr. 2009;98(7):1085-1087.
13. Fleischer DM, Spergel JM, Assa’ad AJ. Pongracic JA. Primary prevention of allergic disease through nutritional interventions. J Allergy Clin Immunol Pract. 2013;1(1):29-36.
14. Abrams EM, Hildebrand K, Blair B, Chan ES; Canadian Paediatric Society. Timing of introduction of allergenic solids for infants at high risk. Canadian Paediatric Society website. Available at: https://www.cps.ca/en/documents/position/allergenic-solids. Published January 24, 2019. Accessed August 14, 2019.
15. National Institutes of Health. Peanut consumption in infancy lowers peanut allergy [press release]. Available at: https://www.nih.gov/news-events/nih-researchmatters/peanut-consumption-infancy-lowers-peanut-allergy. Published February 23, 2015. Accessed August 14, 2019.
16. 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.
17. Saarni S, Gylling HA. Evidence based medicine guidelines: a solution to rationing or politics disguised as science. J Med Ethics. 2004;30(2):171-175.
18. Feeney M, Du Toit G, Roberts G; et al; Immune Tolerance Network LEAP Study Team. Impact of peanut consumption in the LEAP study: feasibility, growth, and nutrition. J Allergy Clin Immunol. 2016;138(4):1108-1118.
19. Bock SA, Munoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. J Allergy Clin Immunol. 2001;107(1);191-193.
20. Rudders SA, Banerji A, Clark S, Camargo CA Jr. Age-related differences in the clinical presentation of food-induced anaphylaxis. J Pediatr. 2011:158(2):326-328.
21. Topal E, Bakirtas A, Yilmaz O, et al. Anaphylaxis in infancy compared with older children. Allergy Asthma Proc. 2013;34(3):233-238.
22. Koplin JJ Peters RL, Dharmage SC, et al; HealthNuts study investigators. Understanding the feasibility and implications of implementing early peanut introduction for prevention of peanut allergy. J Allergy Clin Immunol. 2016;138(4):1131.e2-1141.e2.
23. Turner PJ, Campbell DE. Implementing primary prevention for peanut allergy at a population level. JAMA. 2017;317(11):1111-1112.
24. Sunog R, Eat the Eight: Preventing Food Allergy with Food and the Imperfect Art of Medicine. The Nasiona; 2019.
25. Birch L, Savage JS, Ventura A. Influences on the development of children’s eating behaviours: from infancy to adolescence. Can J Diet Pract Res. 2007;68(1):s1-s56.