If you're a new parent in 2026 and you're trying to figure out when to introduce peanut, egg, dairy, and other common allergens to your baby, you've probably noticed the advice has changed dramatically in the last decade. Your own parents may have been told to wait until age three to introduce peanut. Your pediatrician is likely telling you the opposite: start as early as 4 months. That isn't a contradiction — it's a major shift in evidence-based pediatric guidance, supported by clinical research that has genuinely changed how the medical community thinks about food allergy prevention.

This guide walks through the current recommendations, what the underlying research actually shows, an age-by-age schedule for introducing the major allergens, how to do it safely, and — importantly — when to consult an allergist before you start. It's based on the 2017 NIAID Addendum Guidelines for the Prevention of Peanut Allergy, the 2021 Consensus Guidelines from the AAAAI, ACAAI, and CSACI, and current pediatric standard of care. At the Los Angeles Food Allergy Institute in Burbank, we work with pediatricians across the LA area on early-introduction planning, and this guide is the same information we share with families during pre-introduction consultations.

The Big Picture: Earlier Is Now Better

For most of the past several decades, the American Academy of Pediatrics recommended that parents delay the introduction of common allergenic foods — peanut, egg, fish, and others — until children were older. The reasoning at the time was that delaying exposure would give the immune system more time to mature and reduce the risk of allergy development.

In 2015, the Learning Early About Peanut Allergy (LEAP) study, published in the New England Journal of Medicine, fundamentally challenged that thinking. The trial randomized over 600 high-risk infants (defined as having severe eczema, egg allergy, or both) to either eat peanut-containing foods regularly from 4 to 11 months of age, or to avoid peanut entirely until age 5. The results were dramatic: an 81% reduction in peanut allergy by age 5 in the early-introduction group compared to the avoidance group.

In 2024, the LEAP-On follow-up extended this picture. The protective effect persisted into adolescence: at age 12, only 4.4% of the early-introduction group had a peanut allergy compared to 15.4% of the avoidance group — a 71% reduction sustained over more than a decade.

In response to LEAP, the National Institute of Allergy and Infectious Diseases issued formal Addendum Guidelines in 2017 specifically reversing the delay recommendation for peanut. The 2021 Consensus Approach from the AAAAI, ACAAI, and CSACI expanded this further: introduce peanut, egg, and other major allergenic foods at around 6 months of age, but not before 4 months, regardless of family allergy history.

In other words: delayed introduction does not prevent food allergy. Early introduction, in many cases, does.

When to Consult an Allergist Before Starting

This is the most important section of this post, and it's also the section that gets missed most often.

The current guidelines define three risk levels for peanut allergy in infants, and the recommendation for each is different:

High risk: Severe eczema and/or egg allergy

Infants with severe eczema (eczema requiring prescription topical treatment) or a known egg allergy are at significantly elevated risk of developing peanut allergy. For these infants, the NIAID guidelines specifically recommend:

• Pre-introduction evaluation by an allergist — including skin prick testing or specific IgE blood testing — before peanut is introduced at home.
• Earliest possible safe introduction (4 to 6 months) once testing confirms the infant is not already sensitized.
• In some cases, the first introduction happening in a medical setting with monitoring, rather than at home.

This is the situation where booking an evaluation matters most. The 81% protective effect from the LEAP study was specifically demonstrated in this high-risk group. Skipping the evaluation and either introducing peanut blindly at home or — worse — delaying it indefinitely both increase the risk of a serious allergic reaction.

Moderate risk: Mild to moderate eczema

Infants with mild or moderate eczema (but not severe) are at somewhat elevated risk. For this group, the guidelines recommend introducing peanut at around 6 months — generally safe to do at home, but worth a conversation with your pediatrician and, if either of you has questions, with an allergist.

Low risk: No eczema, no other food allergy

For infants with no eczema or other risk factors, peanut and other allergens can be introduced at home starting at 4 to 6 months when the baby is developmentally ready for solid foods. No pre-introduction testing required.

A note on siblings with peanut allergy

Having an older sibling with peanut allergy does not automatically put your infant in the high-risk category by current guidelines. Recent research has actually challenged whether sibling history is a reliable risk factor, since older siblings may have themselves had delayed introduction. Talk to your pediatrician or an allergist about your specific situation — for many families with one peanut-allergic child, the same evidence-based early introduction approach applies to younger siblings.

When to Introduce Each Allergen: An Age-by-Age Schedule

Here's how the current guidance breaks down by allergen. All ages assume the baby is developmentally ready for solid foods — sitting upright with support, showing interest in food, opening mouth for a spoon. Most babies hit that point around 4 to 6 months.

Around 4 to 6 months

• Iron-rich first foods (general): Single-ingredient purees of vegetables, fruits, or meats. These come before allergens — not because allergens are unsafe, but because the baby needs to be tolerating some solid foods before allergens are introduced.
• Peanut: In infant-safe forms only (see safety note below). For high-risk infants, only after allergist evaluation. For lower-risk infants, anytime in the 4 to 6 month window once solid foods are established.
• Egg: Well-cooked, scrambled, or in baked goods. Whole egg, not just the yolk.
• Dairy (yogurt and cheese): Yogurt and cheese are typically introduced as solids in this window. Cow's milk as a drink is not recommended until age 1.

6 months and beyond

• Tree nuts: In infant-safe forms (smooth nut butters thinned out, or nut flours mixed into foods).
• Sesame: Tahini thinned into other foods, or sesame paste mixed into purees. Sesame allergy is increasingly common, and early introduction matters for it too.
• Wheat: Baby cereals containing wheat, well-cooked pasta, soft bread.
• Soy: Tofu, edamame (mashed), or soy yogurt.
• Fish and shellfish: Well-cooked, soft, boneless. Start with mild fish like salmon or tilapia; shellfish (shrimp) can follow.

After 12 months

• Cow's milk: Whole milk as a beverage, after age 1.
• Honey: Safe after 12 months (the delay is for infant botulism, not allergy).

Safe Forms: How to Actually Introduce Peanut and Tree Nuts

This is the part that frequently confuses new parents. Whole peanuts, peanut pieces, and globs of unthinned peanut butter are all choking hazards for infants. So how do you introduce peanut safely?

The current evidence-based recommendation is to use one of the following forms:

• Peanut powder or peanut flour mixed into infant cereal, pureed fruit, or yogurt. Several commercial brands make peanut-protein products specifically designed for infant early introduction. These are widely available.
• Peanut puff snacks (the dissolvable kind, often labeled for early peanut introduction) once the baby can manage them developmentally.
• Thinned smooth peanut butter — about 2 teaspoons of peanut butter mixed into 2 to 3 teaspoons of warm water, applesauce, or pureed fruit until thin and smooth. Never feed thick peanut butter from a spoon to an infant.

The same logic applies to tree nuts — smooth almond butter, cashew butter, or hazelnut butter, thinned out, or finely ground nut flours mixed into other foods.

Target intake for sustained protection (per NIAID guidance): roughly 2 grams of peanut protein, three times per week — about 2 teaspoons of peanut butter or equivalent. The key is consistency. A single introduction doesn't produce the protective effect; ongoing regular exposure does.

How to Introduce a New Allergen Safely

For each new allergen, the recommended approach is:

1. Introduce when the baby is healthy — not sick, not unusually tired, not in the middle of a difficult day.
2. Introduce at home (or in the clinic, for high-risk infants), in the morning or early afternoon when you can observe the baby for several hours afterward.
3. Start with a small amount. For peanut, about a quarter teaspoon of peanut protein for the first feeding.
4. Observe for about 2 hours. Watch for hives, swelling around the mouth, vomiting, breathing changes, or significant behavior changes.
5. If the first introduction goes well, continue feeding the allergen regularly — for peanut, the target is several times per week to maintain the protective effect.
6. Don't introduce two new allergens at the same time. That way, if a reaction does occur, the cause is clear.

When to Use Epinephrine — Know This Before You Start

Severe allergic reactions in infants during first food introductions are rare but possible. Every family introducing allergenic foods at home should know the signs of a serious reaction and have a plan if one occurs:

• Mild reactions (a few hives around the mouth, mild fussiness) can usually be observed at home and discussed with your pediatrician.
• Signs that require immediate emergency care: widespread hives, swelling of the face or tongue, vomiting, difficulty breathing, wheezing, persistent crying, or significant change in alertness.
• For high-risk infants whose evaluation has identified them as candidates, the allergist may prescribe an epinephrine auto-injector for use at home. For more on this, see our guide to epinephrine auto-injector options.

If a serious reaction occurs at any age, call 911 immediately. Don't drive to the hospital — paramedics carry the medications needed to manage anaphylaxis en route.

A Note for Pediatricians

If you're a pediatrician reading this — or a parent who'd like to share this with your child's pediatrician — this guide is intended as a parent-friendly summary of current NIAID and consensus guidelines. We work closely with pediatric practices across Burbank, Glendale, Pasadena, Sherman Oaks, Studio City, North Hollywood, La Crescenta, and the broader LA area on pre-introduction evaluations for high-risk infants. Referrals can be made directly through our office; we send detailed evaluation summaries back to the primary care team and coordinate on the in-home introduction plan.

The Allergen Introduction Tracker

For families introducing multiple allergens over a span of weeks, it's genuinely useful to have a simple tracker — what was introduced, on what date, in what amount, with what response. We've prepared a one-page printable allergen-introduction tracker that walks parents through the recommended introduction sequence with space to log each new food. Request it through our contact page and we'll send it over.

The Bottom Line for LA Families

If you're a parent in Burbank, Glendale, Pasadena, Sherman Oaks, Studio City, North Hollywood, La Crescenta, or anywhere across the greater Los Angeles area with an infant approaching 4 to 6 months of age, the most important thing to know is that the current evidence-based approach to common allergens is to introduce them earlier, not later. Delayed introduction is not protective. Early introduction, done safely, often is.

If your baby has severe eczema, has been diagnosed with an egg allergy, or you have concerns about food allergy risk for any reason, a pre-introduction allergist evaluation is genuinely worth scheduling. The evaluation involves the standard skin prick and blood testing that insurance typically covers as a specialist diagnostic visit. The output is a clear, specific plan for safe early introduction — often in your own home, sometimes initially at the clinic — and a meaningful reduction in the risk of food allergy developing in the first place.

Schedule a pre-introduction screening at the LAFAI Burbank clinic →

This article reflects publicly available evidence-based guidance on early food introduction in infants as of 2026, including the 2015 LEAP study and 2024 LEAP-On follow-up published in the New England Journal of Medicine, the 2017 NIAID Addendum Guidelines for the Prevention of Peanut Allergy, and the 2021 Consensus Approach from the AAAAI, ACAAI, and CSACI. It is educational and does not constitute medical advice. Specific introduction plans should be discussed with your child's pediatrician or an allergist. Infants with severe eczema, known egg allergy, or other risk factors should be evaluated by an allergist before peanut is introduced at home.

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