A Parent's Guide to the EAT Study on Early Allergen Introduction

The EAT study shows that feeding babies allergy-causing foods early and often can help reduce their food allergy risk. We cover everything parents need to know about the EAT study, including what the findings mean for your family.

Thanks to the landmark EAT study, we now know that introducing babies to allergenic foods like peanut and egg, early and often, can help reduce their risk of developing allergies to these foods. But how was the EAT study conducted, what exactly did it reveal, and what do the findings mean for your family? In this article, we’ll break down everything parents need to know about the EAT study.

The EAT Study: Overview

In the EAT study, babies either ate six common allergy-causing foods consistently for 3-6 months, or avoided these foods completely for at least 6 months. 

  • The six foods were milk, egg, peanut, sesame, whitefish, and wheat.
  • The babies started the study at 3 months of age
  • They were not at increased risk for food allergies.

The aim was to understand the "influence of early exposure to allergenic foods on the subsequent development of food allergy."

Learn more about the landmark EAT study from this 2 minute video from the New England Journal of Medicine: 

Here's our complete guide to the EAT study for parents

Questions Answers

What was the purpose of the EAT study?

To see if introducing allergy-causing foods early and often would reduce babies’ risk of developing allergies to these foods.

Who took part in the EAT study?

  • 1303 infants and their mothers in the UK
  • All starting at 3 months of age
  • All from the general population
  • All exclusively breastfed

Which foods were introduced in the study?

Peanut, cooked egg, cow's milk, sesame, whitefish, and wheat

How was the EAT study conducted?

  • The babies were randomly assigned to two groups
    • One group consumed the six foods starting at 3 months of age
    • The other group avoided these foods for at least 6 months 
  • All mothers continued to breastfeed their babies for 6+ months 
  • Children were checked at 1 year and 3 years of age to see if they developed food allergies

How much of the allergy-causing foods did babies in the "consume" group eat? How often?

  • At 3 months of age, parents started introducing the 6 foods.
    • 2 new foods per week
    • Milk was always first
    • Peanut, egg, whitefish and sesame were introduced in random order
    • Wheat was always last
  • The target amount of each food protein to introduce was 4g total per week. 
  • On average, once babies reached 5 months of age, they were eating each food 2-3 times per week. 
  • Babies needed to keep eating the foods consistently for at least 3-6 months of age. 
  • Parents kept a diary to track how much of each food they fed their baby, and how often.

Were all parents able to introduce the target amounts of each food, consistently for at least 3 months?

No. 57% of parents were not able to follow the dosing requirements.

How did researchers check to see if babies developed allergies?

  • At 1 year and 3 years of age, the babies had clinical exams
    • They were given a skin prick test for each of the 6 foods.
    • If they had a positive skin prick test to a food, or previously had symptoms of a food allergy, they completed a food challenge. 
    • In the food challenge, they were slowly introduced to the food to see if they developed allergy symptoms.
  • In between, parents also completed a questionnaire
    • Every month until their baby was 1 year old
    • Then every 3 months until their child was 3 years old
    • They shared whether their baby had any symptoms of food allergies

What did the results show?

  • Introducing allergenic foods like peanut, egg and milk early and often can reduce babies' food allergy risk by up to 67%
  • Introducing peanut and egg early is especially effective
  • Delaying introduction of common allergy-causing foods can increase food allergy risk


The EAT Study Results

The EAT study's results show that: 

  • Feeding babies common allergy-causing foods early and consistently, starting around 3 months of age, reduces their risk of developing allergies to these foods. 
  • Delaying introduction of these foods increases babies' food allergy risk.

In the per protocol analysis (those babies who ate the recommended amount of the foods), 7.3% of the babies who avoided the six allergy-causing foods (milk, egg, peanut, whitefish, sesame, wheat) developed an allergy to one or more of these foods by 12 months of age.

Meanwhile, only 2.4% of the babies who consumed these foods early and often, between 3 and 6 months of age, developed an allergy to one or more of these foods by 12 months of age.

This represents a 67.12% difference.

Introducing peanut and egg early and often had especially significant results. 


  •  2.5% of the babies in the "avoid" group developed a peanut allergy. 
  • But none of the babies who consistently ate the full study dose of peanut developed a peanut allergy.


  • 5.5% of the babies in the "avoid" group developed an egg allergy.
  • But only 1.4% of the babies who consistently ate the full study dose of egg developed an egg allergy (a 74.55% difference).

Life After the EAT Study: Takeaways for Families

The EAT study shows that early, consistent introduction of allergenic foods like peanut, egg, and milk  can help reduce your baby’s risk of developing a food allergy. Here’s what parents should take away from the EAT study:

  • Introduce common allergy-causing foods like peanut and egg to your baby early and often.
    • This may reduce your baby's risk of allergies to these foods by up to 67%.
  • Consistently introducing these foods, at least 2-3 times per week for 3-6+ months, is just as important as starting early.
  • Delaying the introduction of these foods increases your baby's food allergy risk.
  • If you're breastfeeding, continue to breastfeed while you introduce baby to these foods.

However, the study also shows that consistent introduction can be difficult for families, especially at such an early age. 

  • More than 50% of the parents in the study were unable to follow the full protocol for introducing the foods to their babies. 
  • Many had trouble getting their babies to eat the foods consistently. 
  • Babies whose parents didn't follow the protocol didn't experience the same reduced risk benefits as babies who consistently ate the foods. A primary reason for you to not give up on early, consistent introduction.

Because of the EAT study’s significant findings, new landmark medical guidelines for introducing peanut, were established including guidelines from the AAP.


All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

See the FDA Peanut Allergy Qualified Health Claim at the bottom of our homepage.

About the author: Our Chief Allergist, Katie Marks-Cogan, M.D., is board certified in Allergy/Immunology and Internal Medicine, and treats both pediatric and adult patients. Originally from Cleveland, Ohio, she received her M.D. with honors from the University of Maryland School of Medicine. She then completed her residency in Internal Medicine at Northwestern and fellowship in Allergy/Immunology at the prestigious University of Pennsylvania and CHOP. After finishing training, she moved to Southern California and currently works in private practice. She is a  member of the scientific advisory board for Ready, Set, Food! She currently resides in Los Angeles with her husband, 4-year-old son, and 1-year-old daughter where she enjoys hiking, building LEGO castles with her kids, and cooking with her family.