Emergency first. If this might be anaphylaxis, use epinephrine and call 911.Thoughts of harming yourself: call or text 988.After surgery: trouble breathing or chest pain, call 911.
General information, not medical advice.Read the full note

Epitope Health teaches what published research and FDA labels say, and how strong that evidence is. It cannot know your situation, and nothing here is a diagnosis, a dose for one person, or a decision about whether a food, medicine or procedure suits one person. Those decisions belong with a licensed clinician who can examine you.

If a reaction is happening now, use epinephrine if it has been prescribed and call 911. If you are thinking about harming yourself, call or text 988, any time.

Epitope Health
Menu
Home / Allergy and immune care / Prevention

Early introduction: what LEAP, EAT and the guidelines found about peanut and egg

The trials that changed advice on feeding babies allergenic foods, what the guidelines now say, and what is still unknown.

4 minute read12 sources, each checked word for wordLibrary checked October 18, 2026

In short

  • In the LEAP trial, eating peanut from infancy sharply lowered peanut allergy at age 5 in babies at high risk.E1Strong1
  • US, Canadian and European guidance now describes introducing peanut and egg around 6 months of age, not before 4 months.E2Good2
  • Avoiding allergenic foods during pregnancy or breastfeeding is not recommended as a way to prevent food allergy.E2Good2,3
  • Eczema is the strongest known risk factor for IgE-mediated food allergy, but children without risk factors can still develop one.E2Good2

How sure each claim is:E1StrongE2GoodOfficial textReviewWhat the grades mean

What did the LEAP trial find?

LEAP randomly assigned 640 infants with severe eczema, egg allergy, or both to eat or avoid peanut until 60 months of age.E1Strong1

Among infants whose first skin test was negative, peanut allergy at age 5 was 13.7% in the avoidance group and 1.9% in the eating group. Among those whose first test was positive, it was 35.3% against 10.6%.E1Strong1

The trial concluded that early introduction of peanut significantly decreased peanut allergy in children at high risk.E1Strong1

In the follow-up study, LEAP-On, children who had eaten peanut from infancy to age 5 then avoided it for a year. Peanut allergy did not increase.E1Strong4

The NIAID guideline's full text describes the regular weekly amount used when peanut is introduced. It is about 6 to 7 g of peanut protein a week, over 3 or more feedings. In LEAP, 75% of children in the eating group reported eating at least that much.E2Good5

What about other foods, such as egg?

The EAT trial introduced six allergenic foods early in breastfed babies. In the main analysis, the difference in food allergy (5.6% against 7.1%) was not statistically significant.E1Strong6

Among children who followed the plan as intended, any food allergy was lower with early introduction (2.4% against 7.3%). This included peanut and egg allergy. There was no significant effect for milk, sesame, fish or wheat.E1Strong6

The PETIT trial in Japan introduced heated egg in small steps to babies with eczema, along with aggressive eczema treatment. Egg allergy occurred in 8% of the egg group against 38% of the placebo group.E1Strong7

A pooled analysis of trials looked at when egg and peanut were introduced. It found moderate-certainty evidence that egg at 4 to 6 months and peanut at 4 to 11 months were linked with lower egg and peanut allergy.E1Strong8

What do the guidelines say now?

The NIAID addendum guidelines say peanut allergy can be prevented by introducing peanut-containing foods beginning in infancy. They give separate guidance for infants at different risk levels. This covers when testing is used and whether introduction happens at home or in a clinic.E2Good9

A 2021 consensus from the US and Canadian allergy societies says peanut and egg should be introduced around 6 months of life, but not before 4 months. Screening before introduction is not required but may be preferred by some families. Other allergens should be introduced around this time too.E2Good2

European guidelines suggest introducing well-cooked egg (not raw or uncooked pasteurized egg) as part of complementary feeding. Where peanut allergy is common, they suggest introducing peanut in an age-appropriate form.E2Good10

The American Academy of Pediatrics found no evidence that delaying allergenic foods, including peanut, egg and fish, beyond 4 to 6 months prevents allergic disease.E2Good3

What does not prevent food allergy?

Avoiding common allergens during pregnancy or breastfeeding is not recommended to prevent food allergy.E2Good2,3,10

Hydrolyzed formula in the first year gives no protective benefit against food allergy. European guidelines suggest against soy formula in the first 6 months as a way to prevent it.E2Good2,10

Exclusive breastfeeding is universally recommended, but it has no specific link with preventing any particular food allergy.E2Good2

Moisturizing a baby's skin every day from birth did not prevent eczema in two large trials.E1Strong11,12

What is not known yet

LEAP-On found that a year of avoidance after early eating did not raise peanut allergy, but longer-term effects are not known.E1Strong4

The EAT trial raised the question of whether prevention by early introduction depends on how much of the food is eaten.E1Strong6

Questions you might bring to your clinician

  1. Which risk group does this baby fall into under current guidelines?
  2. Is any testing useful before introducing peanut or egg, or not needed?
  3. Is introduction better done at home or in a clinic in this case?
  4. How can eczema be kept under control in the meantime?

Every claim in this guide was written from its sources and checked against them word for word. Its clinical review by Dr. Recio, whose specialty is anesthesia, is pending; an allergist has not yet reviewed it. This line changes when each review is done.

Sources

Each source opens on PubMed, DailyMed or the publisher's page. Under each one are the exact words from it that this page relies on, copied word for word and checked against the original.

  1. Randomized trial of peanut consumption in infants at risk for peanut allergy. Du Toit G, N Engl J Med, 2015. E1Strong Randomized trial
    The words this page rests on
    Among the 530 infants in the intention-to-treat population who initially had negative results on the skin-prick test, the prevalence of peanut allergy at 60 months of age was 13.7% in the avoidance group and 1.9% in the consumption group (P<0.001). Among the 98 participants in the intention-to-treat population who initially had positive test results, the prevalence of peanut allergy was 35.3% in the avoidance group and 10.6% in the consumption group (P=0.004).
    The early introduction of peanuts significantly decreased the frequency of the development of peanut allergy among children at high risk for this allergy and modulated immune responses to peanuts.
    We randomly assigned 640 infants with severe eczema, egg allergy, or both to consume or avoid peanuts until 60 months of age.
  2. A Consensus Approach to the Primary Prevention of Food Allergy Through Nutrition: Guidance from the American Academy of Allergy, Asthma, and Immunology; American College of Allergy, Asthma, and Immunology; and the Canadian Society for Allergy and Clinical Immunology. Fleischer DM, J Allergy Clin Immunol Pract, 2021. E2Good Consensus statement
    The words this page rests on
    To prevent peanut and/or egg allergy, both peanut and egg should be introduced around 6 months of life, but not before 4 months. Screening before introduction is not required, but may be preferred by some families. Other allergens should be introduced around this time as well.
    There is no protective benefit from the use of hydrolyzed formula in the first year of life against food allergy or food sensitization. Maternal exclusion of common allergens during pregnancy and/or lactation as a means to prevent food allergy is not recommended.
    Eczema is considered the highest risk factor for developing IgE-mediated food allergy, but children without risk factors still develop food allergy.
    Although exclusive breast-feeding is universally recommended for all mothers, there is no specific association between exclusive breast-feeding and the primary prevention of any specific food allergy.
  3. 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. Greer FR, Pediatrics, 2019. E2Good Guideline
    The words this page rests on
    Current evidence does not support a role for maternal dietary restrictions during pregnancy or lactation.
    There is a lack of evidence that partially or extensively hydrolyzed formula prevents atopic disease. There is no evidence that delaying the introduction of allergenic foods, including peanuts, eggs, and fish, beyond 4 to 6 months prevents atopic disease. There is now evidence that early introduction of peanuts may prevent peanut allergy.
  4. Effect of Avoidance on Peanut Allergy after Early Peanut Consumption. Du Toit G, N Engl J Med, 2016. E1Strong Randomized trial
    The words this page rests on
    Among children at high risk for allergy in whom peanuts had been introduced in the first year of life and continued until 5 years of age, a 12-month period of peanut avoidance was not associated with an increase in the prevalence of peanut allergy. Longer-term effects are not known.
  5. Addendum Guidelines for the Prevention of Peanut Allergy in the United States: Report of the NIAID-Sponsored Expert Panel (full text). Togias A, J Allergy Clin Immunol, 2017. E2Good Guideline
    The words this page rests on
    If the decision is made to introduce dietary peanut to the infant's diet, the total amount of peanut protein to be regularly consumed per week should be approximately 6 to 7 g over 3 or more feedings. In the LEAP trial, at evaluations conducted at 12 and 24 months of age, 75% of children in the peanut consumption group reported eating at least this amount of peanut.
  6. Randomized Trial of Introduction of Allergenic Foods in Breast-Fed Infants. Perkin MR, N Engl J Med, 2016. E1Strong Randomized trial
    The words this page rests on
    In the intention-to-treat analysis, food allergy to one or more of the six intervention foods developed in 7.1% of the participants in the standard-introduction group (42 of 595 participants) and in 5.6% of those in the early-introduction group (32 of 567) (P=0.32).
    The trial did not show the efficacy of early introduction of allergenic foods in an intention-to-treat analysis. Further analysis raised the question of whether the prevention of food allergy by means of early introduction of multiple allergenic foods was dose-dependent.
    In the per-protocol analysis, the prevalence of any food allergy was significantly lower in the early-introduction group than in the standard-introduction group (2.4% vs. 7.3%, P=0.01), as was the prevalence of peanut allergy (0% vs. 2.5%, P=0.003) and egg allergy (1.4% vs. 5.5%, P=0.009); there were no significant effects with respect to milk, sesame, fish, or wheat.
  7. Two-step egg introduction for prevention of egg allergy in high-risk infants with eczema (PETIT): a randomised, double-blind, placebo-controlled trial. Natsume O, Lancet, 2017. E1Strong Randomized trial
    The words this page rests on
    In the primary analysis population, five (8%) of 60 participants had an egg allergy in the egg group compared with 23 (38%) of 61 in the placebo group (risk ratio 0·221 [0·090-0·543]; p=0·0001).
    Introduction of heated egg in a stepwise manner along with aggressive eczema treatment is a safe and efficacious way to prevent hen's egg allergy in high-risk infants.
  8. Timing of Allergenic Food Introduction to the Infant Diet and Risk of Allergic or Autoimmune Disease: A Systematic Review and Meta-analysis. Ierodiakonou D, JAMA, 2016. E1Strong Meta-analysis
    The words this page rests on
    There was moderate-certainty evidence from 5 trials (1915 participants) that early egg introduction at 4 to 6 months was associated with reduced egg allergy (risk ratio [RR], 0.56; 95% CI, 0.36-0.87; I2 = 36%; P = .009).
    There was moderate-certainty evidence from 2 trials (1550 participants) that early peanut introduction at 4 to 11 months was associated with reduced peanut allergy (RR, 0.29; 95% CI, 0.11-0.74; I2 = 66%; P = .009).
  9. Addendum guidelines for the prevention of peanut allergy in the United States: Report of the National Institute of Allergy and Infectious Diseases-sponsored expert panel. Togias A, J Allergy Clin Immunol, 2017. E2Good Guideline
    The words this page rests on
    A recent landmark clinical trial and other emerging data suggest that peanut allergy can be prevented through introduction of peanut-containing foods beginning in infancy.
    The addendum provides 3 separate guidelines for infants at various risk levels for the development of peanut allergy and is intended for use by a wide variety of health care providers. Topics addressed include the definition of risk categories, appropriate use of testing (specific IgE measurement, skin prick tests, and oral food challenges), and the timing and approaches for introduction of peanut-containing foods in the health care provider's office or at home.
  10. EAACI guideline: Preventing the development of food allergy in infants and young children (2020 update). Halken S, Pediatr Allergy Immunol, 2021. E2Good Guideline
    The words this page rests on
    The EAACI Task Force suggests introducing well-cooked, but not raw egg or uncooked pasteurized, egg into the infant diet as part of complementary feeding. In populations where there is a high prevalence of peanut allergy, the EAACI Task Force suggests introducing peanuts in an age-appropriate form as part of complementary feeding.
    The EAACI Task Force suggests against the following for preventing food allergy: (i) avoiding dietary food allergens during pregnancy or breastfeeding; and (ii) using soy protein formula in the first 6 months of life as a means of preventing food allergy.
  11. Daily emollient during infancy for prevention of eczema: the BEEP randomised controlled trial. Chalmers JR, Lancet, 2020. E1Strong Randomized trial
    The words this page rests on
    We found no evidence that daily emollient during the first year of life prevents eczema in high-risk children and some evidence to suggest an increased risk of skin infections.
  12. Skin emollient and early complementary feeding to prevent infant atopic dermatitis (PreventADALL): a factorial, multicentre, cluster-randomised trial. Skjerven HO, Lancet, 2020. E1Strong Randomized trial
    The words this page rests on
    Neither early skin emollients nor early complementary feeding reduced development of atopic dermatitis by age 12 months.