Peanuts are a tricky subject when it comes to babies. Starting solid foods is such a fun adventure, but worrying about potential food allergies is not. We put together this guide so you don’t have to worry about feeding your baby peanut butter for the first time.

We’ll walk you through everything you need to know about babies, introducing peanuts, and preventing peanut allergies. This way, you can be confident and prepared when you decide to introduce peanut butter to your baby’s diet. 

Table of Contents


What You Should Know Beforehand:

An Increase in Peanut Allergies

Between 2001 and 2017, the rate of peanut allergies in 1 year olds jumped from 1.7% to 5.2%. This increase in diagnosed allergies has many causes. But it’s possible doctor recommendations to avoid peanuts actually added to their higher frequency. 

In 2015, the LEAP study upended decades of peanut allergy science. It found that introducing peanuts into a baby’s diet early and often actually decreased that baby’s chances of developing a peanut allergy by 81%. 

After the LEAP and PETIT studies were published, the American Academy of Pediatrics changed their recommendations. Now, they tell parents to introduce allergenic foods like peanuts and eggs early and often to reduce your baby’s risk of developing an allergy.

In 2019 the CHILD study validated this new policy by proving that low risk babies were 4 times more likely to develop a peanut allergy if they did not have early and regular exposure to peanuts.

The Causes of Peanut Allergies

Peanut allergies are the body’s overreaction to an otherwise harmless protein. The cause of this overreaction is a combination of genetics, stomach and skin health, and environment. But the exact combination is still unclear. 

With a peanut allergy, the immune system mislabels peanut as harmful. It then creates antibodies specific to peanut, and attacks it the next time it sees it. Things like hives, vomiting or diarrhea, the slowing of the blood flow, and closed airways are how the body gets the peanut out.

Immune antibodies chasing after a peanutEczema, the environment, and your baby’s stomach health play a role in determining whether or not they will develop a peanut allergy.  

Eczema leaves a baby’s skin broken. When the skin is broken, it allows things from the outside world, like peanut, to sneak in. Doctors think a baby’s body might create antibodies to things that break through the skin, like peanut, and attack the next time they see it.

This also happens in babies with a weak microbiome, or helper-bacteria, in their stomachs. Having the wrong bacteria may leave your baby’s stomach lining weak and inflamed. This sometimes causes leaky gut. Doctors think that with leaky gut, food proteins can leak through the gut, triggering  your baby’s immune system to overreact (otherwise known as a food allergy).  

Are Peanut Allergies Genetic?

Peanut allergies are mostly not genetic. Babies are more likely to develop food allergies if they have parents with eczema, asthma, or food allergies. But skin and gut health and the environment a baby grows up in have a greater effect.

For babies, having a parent with:

  • Asthma or eczema doubles the rate of food allergy. 
  • Seasonal allergies nearly doubles the rate of food allergy.
  • A food allergy increases the risk of developing a food allergy almost 6x.
  • Two or three allergic conditions (asthma, eczema, food allergies, seasonal allergies) also doubles or triples the rate of food allergy. 

Even so, children with no family history of allergies still have a 10% chance of developing a food allergy. 

Who Has a Higher Risk of Developing a Peanut Allergy?

Eczema is the biggest indicator of whether or not a baby will develop a peanut allergy. 

Babies who developed eczema by 3 months old and needed prescription strength medicines had a 50% rate of food allergy. Babies who developed eczema closer to 1 year old and needed only emollients had a 5% rate of food allergy. 

You can see this in the graph below:

prevalence of allergies based on severity of evzema

The earlier a baby develops eczema, and the more severe it is, the more likely he will develop food allergies.

Testing for a Peanut Allergy

The only way to test for a peanut allergy is to watch for a reaction after eating peanuts. This is called an oral food challenge.

my son's oral food challenge

Your pediatrician may also perform a peanut allergy skin prick test or blood test. These tests aren’t conclusive. They are based on sensitization to peanut.

child's back after skin prick allergy test

Sensitization means your baby has been exposed to peanuts and their immune system has created antibodies prepared to react. Sensitization to peanut, however, does not confirm an allergy. 

Babies can be sensitized to peanuts without having an allergic reaction when they eat it.

Signs and Symptoms of a Peanut Allergy

It’s important to know the symptoms of peanut allergy before you feed your baby peanut butter, so you know when to seek medical attention. 

The most common signs of a peanut allergy in babies include: 

  • Redness around the mouth or skin that came into contact with peanut
  • Hives 
  • Stomach distress such as vomiting or diarrhea
  • Runny or stuffy nose, sometimes with clear discharge
  • Redness or itchiness of the nose
  • Swelling of the face, including puffiness around the eyes

redness around the mouth after allergic reaction

face swelling during an allergic reaction

More severe symptoms also include:

  • Coughing
  • Difficulty breathing
  • Swelling of the mouth, including the lips and possibly tongue
  • Fever of 97 degrees or higher
  • Swelling of the throat and difficulty swallowing
  • Weak pulse
  • Losing consciousness

Infants 4-6 months old are much more likely to have hives and vomiting during an allergic reaction rather than one of the more severe symptoms. More severe symptoms happen more often in children 2-6 years old.  

So introducing allergens around 4-6 months old actually decreases your baby’s risk of having a severe reaction

chance of allergy symptoms based on age

Allergic reactions to peanut butter mostly happen immediately. In rare cases, reactions can happen up to 4 hours later. 

You can treat mild reactions to peanut with an age-appropriate amount of an antihistamine like Benadryl. But you should still contact your doctor’s office and continue to watch them for a few hours. 

Bring your baby to an urgent care center or emergency room immediately if they have multiple symptoms involving 2 body systems (like skin and stomach issues) or a severe reaction.

How and When to Feed Your Baby Peanut for the First Time

1. Understand Your Baby’s Peanut Allergy Risk Factors

The current guidelines from the American Academy of Pediatrics decide when a baby should start eating peanuts based on the severity of their eczema. 

when to introduce peanut based on eczema

4- 6 month old babies that have:

  • No eczema or food allergies should start eating peanut 3 times a week at home anytime after they can eat solid foods. 
  • Mild eczema that responds to emollients or over-the-counter medicines should start eating peanut-containing foods 3 times a week at home starting no later than 6 months old. 
  • Severe eczema that requires prescription drugs, an egg allergy, or both should see a doctor to get tested for peanut sensitization
    • Babies who are not sensitized should begin eating peanuts 3 times a week. 
    • Babies who are sensitized, but pass a food challenge, should begin eating peanuts 3 times a week.


2. Determine if They are Developmentally Ready

With your baby’s risk factors in mind, babies can start eating peanut-containing foods as soon as they have tolerated one or two other solids like baby cereal.

While your baby is ready to start eating peanut-containing foods, peanut butter, whole peanuts, chopped or crushed peanuts, and even whole peanut puffs are choking hazards for babies 4 to 10 months old. 


3. Prepare Peanuts Safely for Your Baby to Eat

There are a few safe ways to feed your baby peanut for the first time. 

  1. Mix 2 teaspoons or 1 packet of Lil Mixins Infant Peanut Powder into their food. Unlike most peanut butters, Lil Mixins is made with just peanuts — no added sugars, no added salt.Mixing in peanut powder into baby food
  2. Thin 2 teaspoons of creamy peanut butter with warm water. Allow it to cool, then feed it to your baby directly or mix it into their food.Thinning peanut butter to mix into baby food
  3. Mash 20 peanut puffs, like Bambas, into warm water. Allow it to cool, then feed it to your baby directly or mix it into their food. Melting peanut puffs with water to mix into baby food

When feeding your baby any new food, it’s important to have the time to watch them for up to 4 hours afterwards to look for a reaction. 


4. Continue Feeding Your Baby Peanut

Once your baby has eaten peanut for the first time and you see no reaction, continue adding about 2g of peanut protein (2 scoops of Lil Mixins, 2 teaspoons of peanut butter, 20 Bambas puffs) to their meals a few times a week until they turn one.

Feeding your baby peanuts early and often is the single best way to reduce their chance of developing a peanut allergy.

Living With a Peanut Allergy

Unfortunately, babies can still develop a peanut allergy even if you do everything “right.” But managing a peanut allergy is much easier than it used to be. 

Common Peanut-Containing Foods

This list is not exhaustive:

  • Baked goods. Cookies, pastries, pies and other baked goods are often made with peanuts
  • Candy ( Reese’s) including nougat and marzipan
  • Ice cream, frozen desserts, puddings, and hot chocolate are often peanut flavored
  • Cereals and granola may have peanut 
  • Trail mix
  • Chili and soups. Peanuts or peanut butter are sometimes used as thickeners.
  • Energy bars
  • Indian foods
  • Thai food
  • Chinese food
  • African foods
  • Veggie burgers or other meat replacements
  • Sauces. These may include barbeque sauce, hot sauce, pesto, gravy, mole sauce, glazes, or marinades.
  • French fries and other friend foods cooked in peanut oil (maybe)
  • And more

Thanks to the Food Allergen Labeling and Consumer Protein Act passed in 2004, the presence of the eight major food allergens — milk, egg, fish, crustacean shellfish, tree nuts, wheat, peanuts, soybeans — in any packaged food must be declared using a recognizable name in the ingredients list. 

Allergenic ingredients will show up in two ways on food labels: 

food label example with allergens listed

The FDA rules do not require manufacturers to list facility and potential cross-contact allergens.

Preventing Accidental Peanut Exposure

Preventing accidental exposure is all about informing those around you about your baby’s peanut allergy.

Rules to follow:

  • Make sure everyone bringing your child food (family, friends, servers) is aware of their peanut allergy.
  • Always ask about the ingredients and cooking oils used to prepare food.
  • Give family members/caregivers an emergency plan and walk through it with them.
  • Identify which brands and specific products you’re comfortable with.
  • Set up a meeting and discuss your child’s peanut allergy with any daycare or school they will attend.
  • Create a 504 plan with your child’s school. 

In Case of Emergencies

Having an exposure plan in place and access to epinephrine is essential to keeping your child safe in case of accidental exposure to peanut. 

You can download an exposure plan here from the Food Allergy Research and Education organization. 

Exposure plans outline three steps you should take in the case of accidental exposure:

  1. Use an antihistamine like Benadryl at the earliest signs of a reaction.
  2. If two body systems are involved (like skin AND stomach), use epinephrine and go to the ER.
  3. If any critical body systems are involved (trouble breathing, fast heart rate, drop in blood pressure), use epinephrine and got to the ER. 

Even if epinephrine seems to help the reaction, you must take your child to the emergency room. Symptoms can worsen or improve for several hours after exposure, so it’s important to be under the care of trained health care providers until given the all-clear.

Now Let’s Get to It! 

You should have all the tools you need to make an informed decision about introducing your baby to peanuts. 

You understand the causes of peanut allergies, you know what can prevent them, and you’re ready to start an early introduction routine. 

And chances are, once you introduce peanut butter, you’ll have a peanut-lover on your hands!