Introducing Peanuts, Eggs, and other Common Allergens to Infants

Should I introduce peanuts and eggs to my infant?

Much advice from the past decade about when to introduce peanuts and eggs into the diet has changed. Recent research shows that early introduction and regular consumption of peanuts and eggs decreases the risk of developing allergies to these foods. In general, it is recommended that infants without an existing peanut or egg allergy should be introduced to peanuts and eggs at around 6 months of age but not before 4 months of age.

What are the risk factors for food allergies? 

Infants with severe eczema have the highest risk of food allergies. Infants with existing food allergies also have higher risk for having other food allergies. Additional risk factors include mild to moderate eczema and a family history of food allergy or other allergic disease.

What is the best time to introduce peanuts and eggs into my child’s diet?

If your child has moderate to severe eczema and/or other food allergies, talk to your pediatrician or allergist about a plan for if, when, and how to consider introducing peanuts and eggs after 4 months of age and by 6 months of age. Early introduction may help protect against developing a peanut or egg allergy. Your doctor might recommend testing, such as blood allergen or skin prick testing to peanuts before introduction. However, if you are comfortable, you may cautiously introduce peanuts and eggs at home without further evaluation or testing. 

If your child does not have moderate to severe eczema and does not have other food allergies, introduce peanuts and eggs, one at a time, around 6 months of age and not before 4 months of age. No testing is needed before introduction. 

What are some common symptoms of a food allergy reaction?

Symptoms usually develop within minutes after eating the food but can occur after 1–2 hours. Allergic reactions can be mild or severe and may involve multiple parts of the body. Anaphylaxis is a severe whole-body allergic reaction. If your child develops anaphylaxis you should administer epinephrine, if your child has a prescription for it, and call 911. Severe anaphylaxis is highly unlikely to happen during an infant’s first exposure to a new food, but it is still important to know what to look for.

Mild symptoms of an allergic reaction are ONE of the following. However, if your child has a combination of symptoms involving two parts of the body, this is considered a severe reaction.

• Hives (itchy, raised, red bumps on the skin) on one part of the body
• Runny nose and sneezing multiple times
• Upset stomach, throwing up once
• Itchy tongue or lips

Severe symptoms include any of the following. If your child develops any of these symptoms, you should administer epinephrine, if your child has a prescription for it, and call 911. 

• Two or more mild symptoms (more than one body part involved)
• Hives on most of the body
• Persistent coughing
• Difficulty breathing and wheezing
• Sudden fatigue, change in skin color (pale, blue)
• Repetitive throwing up or diarrhea 

How do I know if my child is ready to start solid foods?

It is important to feed your infant new foods only when they are healthy (without a cold, vomiting, diarrhea, or other illness) and when an adult is available to watch for any adverse reactions. 

Follow your baby’s cues rather than trying to make them eat a certain amount of food when introducing solid (complementary) foods. Generally, at around 4–6 months of age children are developmentally ready to start complementary feeds. Signs that your baby is developmentally ready include:

• Your baby can hold their head up steadily and sit with some support.
• Your baby shows interest in foods others are eating and opens their mouth when food approaches.
• Your baby does not push food out of their mouth with their tongue.

Start with a few foods with lower allergy risk, such as a fruits, vegetables, or infant cereal, before introducing common allergens like eggs and peanuts. Although there are no specific recommendations for how often to introduce new foods, it is no longer thought necessary to wait 3 days between introducing new foods. It is reasonable to introduce common allergens such as peanuts and eggs one at a time. 

How should I introduce peanuts into my child’s diet?

Peanut butter can be a choking hazard for infants. Whole peanuts are choking hazards and are not recommended until at least 4 years of age. Below are some ways to mix or thin peanut butter to a safe consistency for your infant. Choose smooth peanut butter rather than crunchy peanut butter, and choose a product without added sugar, salt, and oil. 

When feeding your infant peanuts for the first time:

• Prepare a full portion of one of the following peanut-containing recipes:
  • Thin peanut butter by mixing 2 teaspoons peanut butter with 1 tablespoon warm water.
  • Mix 2 teaspoons peanut butter with 2–3 tablespoons of fruit or vegetable puree.
  • Mix 2 teaspoons of peanut butter powder, PB2®, or peanut flour with 2–3 tablespoons of fruit or vegetable puree.
  • Dissolve 21 Bamba® peanut puffs with 4–6 teaspoons of water. Infants >7 months of age tolerating dissolvable textures may have intact peanut puffs.
• Offer a small amount on the tip of a spoon or your finger.
• Wait 10 minutes. If your infant has no allergic reaction (see symptoms above) after this small taste, then slowly offer the remaining portion at the infant’s usual feeding speed. Follow your baby’s cues—it is okay if your baby does not finish the full portion. 

Once peanut is introduced, how often should I offer a serving to my child?

Offer a serving (about 2 teaspoons) to your infant three times per week as tolerated. Offering peanuts to your infant consistently is important to maintain tolerance to the food. If your infant is not interested in purees, try a peanut-containing snack such as Bamba®. You can also finely grind peanuts and use them as breading for finger foods or mix them into other foods such as hot cereals. 

How should I introduce eggs into my child’s diet?

Introduce cooked egg to your infant. Avoid raw or liquid pasteurized egg. Hard-boiled egg can be mashed or pureed and mixed into other foods. Other ideas include well-cooked scrambled eggs or omelets cut into strips. Eggs also can be incorporated into French toast or pancakes cut into strips.

Once egg is introduced, how often should I offer a serving to my child?

Consistently offer 1/3 of a cooked egg 2–3 times per week. It is important to consistently offer the cooked egg to maintain tolerance to the food.

What about other common food allergens, such as dairy products, soy, tree nuts, wheat, fish, shellfish, and sesame? Should I introduce a variety of foods to my infant?

More research is needed to determine if early introduction of these common allergens may help prevent allergies to these foods. There is no evidence that delaying introduction of these foods prevents or causes food allergies. There is some evidence that an increased variety of foods in an infant’s diet is associated with decreased incidence of food allergies later in childhood. Introduce your infant to a wide variety of foods including these common allergens. 

Remember to follow your infant’s cues. The parent’s job is to offer a wide variety of foods, but the infant should be in charge of what food they choose to eat. If your child refuses certain foods, continue to offer these foods and encourage exploration through touch. It may take 10 exposures to a food before an infant readily accepts the food.

What are some ideas for serving other common food allergens to infants?

Sesame can be introduced as tahini (sesame seed paste) mixed into purees or as hummus made with tahini. Most commercially packaged hummus contains tahini. Tree nut butters can be diluted with water and mixed with purees and hot cereals. Tree nuts can be finely ground in a food processor or using a microplane grater and then used as breading for finger foods or mixed into purees or baked goods. Older infants can be offered thin layers of tree nut butters on toast or fruits such as banana. Soy can be introduced in the form of silken tofu mashed and mixed into purees or cut into stick-shaped strips and offered as a finger food. 

Authors: Anthony Porto, MD, Lisa Bartnikas, MD & Wendy Elverson, RD
Editor: Riha Bhatt, MD
November 2024