Table 1.

Summary of guidelines for the primary prevention of food allergies [10, 19, 42]

	CPS/CSACI guidelines (2021) [19]	North American Consensus guidelines from the AAAI, ACAAI and CSACI (2020) [42]	NIAID guidelines (2017) [10]
BF	• BF for up to 2 years and beyond	• EBF recommended for all mothers • No association between EBF and the prevention of food allergy	• No specific recommendation provided • Guideline panel recognized that although early introduction of peanut may seem to depart from recommendations for EBF, evidence (LEAP) suggests that introduction of peanut does not affect the duration or frequency of breastfeeding
Pregnant or BF mothers	• Modifying the maternal diet to prevent food allergy not recommended (insufficient evidence)	• Maternal exclusion of common allergens not recommended • Use of any food supplement not supported	• No recommendation
Introduction of food allergens	• High-risk infants: introduce allergenic foods (e.g., cooked [not raw] egg, peanut) at about 6 months and not before 4 months of age • Low-risk infants: introduce allergenic foods at around 6 months	• All infants: introduce peanut and cooked hen’s egg starting around age 6 months but not before age 4 months • Do not delay the introduction of other allergenic foods (cow’s milk, soy, wheat, tree nuts, sesame, fish, shellfish) at around age 6 months but not before 4 months • New foods, including commonly allergenic foods, can be introduced on successive days, with no evidence of harm to this approach	• Highest risk infants (severe eczema and/or egg allergy): introduce age-appropriate peanut-containing food (see Table 2) as early as 4–6 months of age • Infants with mild-to-moderate eczema: introduce age-appropriate peanut-containing food around 6 months of age • Infants without eczema or any food allergy: freely introduce age-appropriate peanut-containing foods in the diet, together with other solid foods
Continued intake	• Once allergenic foods have been introduced, ensure regular, ongoing ingestion of age-appropriate serving sizes (i.e., a few times a week) to maintain tolerance	• No frequency, just add as regular part of diet	• Children who demonstrate tolerance to peanut, including those in the high-risk category, should eat peanut-containing foods regularly to maintain tolerance (i.e.,. 6–7 g of peanut protein [see Table 2] per week, divided into 3 or more feedings)
Formula	• When CMF has been introduced in an infant’s diet, make sure that regular ingestion (as little as 10 mL daily) is maintained to prevent cow’s milk allergy • For mothers who cannot or choose not to breastfeed, hydrolyzed formulas should not be recommended to prevent atopic conditions (e.g., eczema, asthma, allergic rhinitis) in either high- or low-risk infants	• Recommends against the use of any hydrolyzed formulas for prevention of food allergy or sensitization	• No recommendation
Pre-emptive screening	• Not recommended (risk of a severe reaction on the first exposure to an allergen is extremely low)	• Not required	• For high-risk infants, SPT or specific IgE blood tests recommended before introducing peanut

AAAI, American Academy of Allergy, Asthma & Immunology; ACAAI, American College of Allergy, Asthma and Immunology; BF, breastfeeding; CMA: cow’s milk allergy; CMF: cow’s milk formula; CPS, Canadian Pediatric Society; CSACI, Canadian Society of Allergy and Clinical Immunology; EBF, exclusive breastfeeding; IgE, immunoglobulin E; LEAP, Learning Early About Peanut Allergy study; NIAID, National Institute of Allergy and Infectious Diseases; SPT, skin prick testing