Tiny Taste guides

How to introduce common allergens to your baby

Offer common allergens like peanut and egg early, once your baby is eating food and has handled a few first foods, usually around 6 months. Waiting longer does not prevent food allergy, and for peanut, early and regular servings lower the risk. If your baby has severe eczema or an egg allergy, talk with your pediatrician first.

Why the advice changed

For years, parents were told to keep peanut and other allergens away from babies. Newer research found no benefit to waiting¹. In 2015, a major study found that introducing peanut early, with regular servings after that, prevented peanut allergy in babies at high risk of it. A follow-up of the same children showed the protection lasted. Studies have also found a protective effect from introducing egg early¹.

That study, called LEAP, was funded by the National Institute of Allergy and Infectious Diseases. Introducing peanut to high-risk babies was safe and led to an 81 percent relative reduction in peanut allergy. NIAID then issued guidelines in 2017 on preventing peanut allergy².

The nine major food allergens

In the United States, nine foods are recognized as major food allergens: milk, egg, fish, crustacean shellfish (like shrimp and crab), tree nuts, peanut, wheat, soy, and sesame³. You do not need to offer them all at once.

Check your baby's risk first

A baby who has, or has had, severe eczema that keeps coming back, or an immediate allergic reaction to any food (especially egg), is considered at high risk for peanut allergy. Talk with your pediatrician before offering the highly allergenic foods¹. Testing for peanut allergy is recommended for babies with severe eczema, an egg allergy, or both⁴. Most other babies can start at home.

Step by step

1. Start with a few easy foods. Begin with a few foods that rarely cause allergies, like infant cereal or pureed fruit. Once those go well and your baby has no extra risk, move on to the common allergens¹.
2. Pick a calm time. Choose a day your baby is well, when you can stay close and watch them for a while afterward.
3. Use a baby-safe form. For peanut, thin a little peanut butter into infant cereal, a fruit puree, or yogurt, or dissolve it in breast milk or formula and feed it by spoon¹. Never give whole peanuts or tree nuts, or a chunk or spoonful of nut butter; these are choking hazards¹⁵. Cook egg well, as in scrambled or hard-boiled egg¹. Whole milk yogurt is a good way to offer dairy, since cow's milk as a drink waits until 1 year¹.
4. Start small. Offer a small taste. If your baby shows no signs of a reaction, slowly offer more¹.
5. One new food at a time. The AAP suggests waiting at least a day before starting another new food¹. CDC suggests 3 to 5 days between new foods⁶.
6. Keep it on the menu. Once a food goes well, keep serving it regularly. The AAP gives examples of regular portions, such as 2 teaspoons of peanut butter or about a third of a well-cooked egg¹.

Signs of a reaction

Food allergy symptoms can show up on the skin (hives, itchy rash, swelling), in breathing (sneezing, wheezing, coughing, throat tightness, a runny nose), in the stomach (vomiting, diarrhea, trouble swallowing), or in circulation (skin paler than usual, fainting, loss of consciousness). Babies may also rub their eyes, keep sticking out their tongue, cry hard, arch their back, or seem floppy⁷.

For mild signs like a few hives, a rash, or one vomit, stop the food and call your pediatrician¹. For trouble breathing, swelling of the tongue or throat, or a baby who suddenly turns pale or floppy, call 911 right away. Epinephrine is the main treatment for a severe reaction, called anaphylaxis. If your child has been prescribed epinephrine, give it first and then call 911⁷.

Tiny Taste's guide to allergic reactions goes into more detail.

This is general information, not medical advice. Ask your baby's doctor about your own baby.