First foods and allergens, without the fear

Medically-informed · Sources: NIH/NIAID, AAP · Updated July 2026 · 4 min read

The guidance flipped — here's the short version

For years parents were told to delay allergenic foods. Research — most famously the LEAP trial on peanut — showed the opposite: early, regular exposure in infancy is associated with a lower chance of developing some food allergies. Current US guidance supports introducing common allergens around the start of solids, roughly 4–6 months for peanut in guidance informed by LEAP, once a few first foods have gone smoothly. The fear-based delay era is over.

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The big nine, baby-format

Peanut (as thinned smooth peanut butter or peanut-puff snacks softened — never whole nuts), egg (well-cooked), cow's-milk products like yogurt as an ingredient (still not milk as the main drink before one year), wheat, soy, tree nuts as smooth butters, fish, shellfish, and sesame. One new allergen at a time, early in the day so you can watch, two or three days before the next newcomer — and once introduced, keep it in rotation; regular exposure is part of the point.

Is this normal for your baby?

FirstWeeks answers with your baby’s age and today’s log in mind — with pediatric sources attached.

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What a reaction looks like

Most reactions, if they happen, are mild and show up within minutes to a couple of hours: hives, redness around the mouth, vomiting. Stop the food and call your pediatrician to plan next steps. Emergency signs — trouble breathing, swelling of lips or tongue, widespread hives with vomiting, sudden floppiness or pallor — mean calling emergency services now, not observing. Writing down the food, the amount and the clock time turns a scary moment into usable clinical information.

Who should talk to a doctor first

Babies with severe eczema or an existing egg allergy are the higher-risk group — for them, guidance recommends involving your pediatrician before introducing peanut, sometimes with testing or a supervised first taste. A strong family history of food allergy is also worth a conversation. Higher risk changes the route, not the destination: these babies often benefit most from getting introduction right.

The calm bottom line

Feed the family's normal foods in safe textures, introduce allergens one at a time and keep them coming, know the emergency signs, and log what happened. That's the entire protocol — no specialty products required.