--- title: "Allergen Introduction for Babies: When and How to Start | Dalo Baby" description: "Current guidance introduces allergens early, not late. When to start, how to offer peanut, egg, dairy and the rest safely, what a reaction looks like, and when to see a doctor first." canonical: https://dalofamilyapps.com/learn/solids/allergen-introduction --- [Home](/)/[Knowledge Hub](/learn)/[Solids](/learn/solids) # Allergen introduction: when and how to start [Dalo Baby Editorial](/learn/editorial-policy)Published September 3, 2026Last reviewed September 3, 20264 min read Introduce common allergens once solids are established, generally from around six months and never before 17 weeks. Delaying peanut and hen's egg beyond 6–12 months may increase allergy risk. Offer one allergen at a time, earlier in the day, in an age-safe form, then keep it in the diet regularly. Severe eczema or a known allergy warrants medical advice first. ![Allergen introduction: when and how to start](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F751face49b8398ea9bf080cede7b005a9bd8fcc5-1376x768.jpg%3Frect%3D176%2C0%2C1024%2C768%26w%3D800%26h%3D600%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ## Key takeaways - Introduce allergens early — delaying peanut and egg beyond 6–12 months may raise the risk. - Start once solids are established, generally around 6 months and never before 17 weeks. - Severe eczema or an existing food allergy? Speak to a doctor before peanut at home. - One allergen at a time, earlier in the day, then keep it in the diet regularly. - This is introduction, not the milk ladder — reintroduction after a diagnosis needs a specialist. In this article 1. [Early, not late](#early-not-late) 2. [Start when solids are established](#start-when-solids-are-established) 3. [How to introduce one](#how-to-introduce-one) 4. [The form matters as much as the food](#the-form-matters-as-much-as-the-food) 5. [What a reaction looks like](#what-a-reaction-looks-like) 6. [This is not the milk ladder](#this-is-not-the-milk-ladder) 7. [A reasonable order](#a-reasonable-order) The advice on this changed direction completely. Parents who had older children a decade ago were told to hold allergens back; the guidance now says the opposite. If you have heard both, the newer version is the one supported by trial evidence. ## Early, not late The LEAP trial randomised 640 infants at high risk of peanut allergy — those with severe eczema, egg allergy, or both — to either eat peanut regularly from between four and eleven months, or avoid it until five years old.[\[3\]](#ref-a3) 81% relative reduction in peanut allergy among infants who ate peanut early rather than avoiding it[\[2\]](#ref-a2) Follow-up found the protection lasted into adolescence, did not affect how long or how often those infants breastfed, and did not affect growth. That result is why US guidance now recommends introducing peanut in the first year rather than delaying it.[\[3\]](#ref-a3) UK guidance reaches the same place from the other direction: delaying peanut and hen's egg beyond six to twelve months may increase the risk of becoming allergic to them.[\[1\]](#ref-a1) ## Start when solids are established Allergens go in after your baby has started solids and tolerated a few first foods — generally from around six months, and not before seventeen weeks. There is no advantage in making an allergen the very first thing your baby eats.[\[1\]](#ref-a1) Talk to your doctor first if this applies Infants with severe eczema, an existing diagnosed food allergy, or both are the one group guidance says should be assessed before peanut is introduced at home. That may mean testing, or a first taste given in a clinic. Everyone else can introduce at home. ## How to introduce one ### Introducing a new allergen at home One allergen at a time, so that if something happens you know what caused it. 1. 1 Pick a calm day, earlier in the day Not when your baby is unwell, teething badly, or just after a vaccination. Earlier in the day means you have waking hours to watch them, rather than putting them to bed straight after. 2. 2 Offer a small amount, in a safe form A smear of thinned peanut butter, a little well-cooked egg, a spoon of yogurt. Never whole nuts, and never a thick spoonful of nut butter on its own. 3. 3 Wait and watch Most reactions appear within minutes, though they can take up to two hours. Introduce nothing else new that day. 4. 4 Build up, then keep it in the diet If there is no reaction, offer a slightly larger amount next time, then keep that food in the regular rotation. Tolerance is maintained by continued exposure, not by a single successful taste. 5. 5 Move on to the next allergen Leave a couple of days between new allergens so any delayed reaction is still attributable. ## The form matters as much as the food Every allergen has a version that is safe for a baby and a version that is a choking hazard. The allergen advice and the choking advice have to be followed at the same time. - Peanut — thinned [peanut butter](/learn/food/peanut-butter) stirred into yogurt or purée, or a peanut puff. Never whole peanuts, which stay off the menu until five.[\[1\]](#ref-a1) - Tree nuts — [almond butter](/learn/food/almond-butter) and other smooth nut butters, thinned. Ground or flaked nuts, never whole. - Egg — [well-cooked egg](/learn/food/egg-yolks). Raw or lightly cooked egg is a separate food-safety question.[\[1\]](#ref-a1) - Cow's milk — as [yogurt](/learn/food/plain-greek-yogurt) or cheese in food from six months. Cow's milk as a main drink waits until twelve months. - Sesame, soy, wheat, fish and shellfish — introduced the same way, in an age-appropriate texture. Cut it for the age, not just for the allergen A safe allergen served in an unsafe shape is still unsafe. Our guide on cutting food by age covers the shapes and sizes that matter at each stage. ## What a reaction looks like Most reactions are mild: redness or hives around the mouth, a rash, some vomiting. These usually appear within minutes and up to two hours after eating.[\[1\]](#ref-a1) Cow's milk allergy can behave differently, with symptoms taking up to three days to appear and looking more like reflux, eczema or unsettled digestion than a classic allergic reaction.[\[1\]](#ref-a1) When it is an emergency Swelling of the lips, tongue or throat, noisy or difficult breathing, a sudden change in colour, or a baby who becomes floppy or unresponsive is anaphylaxis. Call emergency services immediately. Do not wait to see whether it settles. ## This is not the milk ladder Introducing an allergen to a baby who has never reacted to it is a different thing from reintroducing a food to a child with a diagnosed allergy. The milk ladder, the egg ladder and protocols like them are for the second situation, and they belong under the supervision of an allergist or a paediatric dietitian. If your child has a diagnosed allergy, follow the plan your specialist gave you rather than anything on this page. ![](/_next/image?url=%2Fimages%2Fsmart-solids-icon.webp&w=256&q=75&dpl=dpl_HDQuuA58EiAncPne4fumhEvNhdFC) Dalo Solids Track what you have introduced Dalo Solids carries an allergen rating for every ingredient and keeps a record of what your baby has already tried, so you are not reconstructing it from memory. [Dalo Solids](/apps/dalo-solids) ## A reasonable order There is no evidence that one sequence beats another, so the order below is about practicality: the two with the strongest trial evidence first, then the rest as they fit into meals you are already making. - Weeks 1–2 — establish a few non-allergenic first foods. - Weeks 3–4 — peanut, then egg. These are the two with the clearest evidence behind early introduction.[\[4\]](#ref-a4) - Weeks 5–8 — cow's milk (in food), then wheat, then soy. - Weeks 9+ — sesame, tree nuts, fish, then shellfish. Once each one is tolerated, keep it in the diet regularly. This schedule is a default, not a prescription — a baby who is already eating a food happily does not need to wait for its week. In this article 1. [Early, not late](#early-not-late) 2. [Start when solids are established](#start-when-solids-are-established) 3. [How to introduce one](#how-to-introduce-one) 4. [The form matters as much as the food](#the-form-matters-as-much-as-the-food) 5. [What a reaction looks like](#what-a-reaction-looks-like) 6. [This is not the milk ladder](#this-is-not-the-milk-ladder) 7. [A reasonable order](#a-reasonable-order) ## References & disclaimer We link every source we used. Where guidance differs by country, we cite the authority that applies where you are. 1. 1. [Baby food allergies: introducing foods that could trigger a reaction](https://www.nhs.uk/best-start-in-life/baby/weaning/safe-weaning/food-allergies/) NHS · Guideline 2. 2. [Addendum Guidelines for the Prevention of Peanut Allergy in the United States](https://www.niaid.nih.gov/sites/default/files/addendum-peanut-allergy-prevention-guidelines.pdf) NIAID (NIH) · 2017 · Guideline 3. 3. [Introducing Peanut in Infancy Prevents Peanut Allergy into Adolescence](https://www.niaid.nih.gov/news-events/introducing-peanut-infancy-prevents-peanut-allergy-adolescence) NIAID (NIH) · Study 4. 4. [Updates in Food Allergy Prevention in Children](https://publications.aap.org/pediatrics/article/152/5/e2023062836/194356/Updates-in-Food-Allergy-Prevention-in-Children) Pediatrics (AAP) · 2023 · Review * * * Before you act on this This guide is general information about healthy, full-term babies. It does not replace advice from your paediatrician, health visitor, midwife or dietitian, who know your baby. If you are worried about your baby's feeding, growth, breathing or sleep, contact a health professional. ## Questions, answered Do I have to introduce allergens in a particular order? No. There is no evidence that one sequence works better than another. Peanut and egg have the strongest trial evidence behind early introduction, so many parents start there, but what matters far more is that each allergen goes in during the first year and then stays in the diet. How much do I need to give? Small and regular beats large and occasional. In the LEAP trial the target was roughly 6–7 grams of peanut protein spread across three or more feedings a week. For most families that translates to offering a familiar allergen a few times a week rather than measuring anything. What if my baby has eczema? Mild eczema is not a reason to delay — if anything, eczema is a reason to make sure allergens go in early rather than late. Severe eczema is the specific case where guidance recommends talking to your doctor before introducing peanut at home, because it is associated with a higher risk of existing sensitisation. ![Dalo Solids](/_next/image?url=%2Fimages%2Fsmart-solids-icon.webp&w=128&q=75&dpl=dpl_HDQuuA58EiAncPne4fumhEvNhdFC) Get it on your phone Dalo Solids [Dalo Solids](/apps/dalo-solids) Part of [Starting solids: the complete guide](/learn/solids/starting-solids) ## Keep reading [ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F3cc74a688f1c3dbf8618c469daf594b946325154-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### How to cut food by age: sizes, shapes and safety Two principles cover almost every food: cut round shapes lengthways, and soften firm ones until they squash between your fingers. How the cut changes from 6 months to 18 months and beyond. ](/learn/solids/how-to-cut-food-by-age)[ ![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2Fba27f81e6ab5f9f3aa94a2c4dbd4ea5753ca1e3c-1376x768.jpg%3Frect%3D7%2C0%2C1363%2C768%26w%3D440%26h%3D248%26fit%3Dcrop%26auto%3Dformat&w=3840&q=75) ### Gagging vs choking: how to tell the difference Gagging is loud and normal. Choking is silent and an emergency. How to tell them apart, what actually causes choking, and when frequent gagging is worth raising with a professional. ](/learn/solids/gagging-vs-choking) ## Try the free tools - [Is your baby ready for solids?](/tools/solids-readiness-quiz) ## In the food database [![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2Faf754b8de100fec1b1caec8a5d7bb0be6da27231-600x600.webp%3Fw%3D64%26h%3D64%26fit%3Dcrop%26auto%3Dformat&w=64&q=75)Peanut Butter](/learn/food/peanut-butter)[![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2Fe7e98cd8ea2f0c02150acbd513ecfb790277011e-600x600.webp%3Fw%3D64%26h%3D64%26fit%3Dcrop%26auto%3Dformat&w=64&q=75)Almond Butter](/learn/food/almond-butter)[![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F011090e146bb0b3ef0bf958a0959130d89c32c23-600x600.webp%3Fw%3D64%26h%3D64%26fit%3Dcrop%26auto%3Dformat&w=64&q=75)Egg Yolks](/learn/food/egg-yolks)[![](/_next/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2F87uht7oc%2Fproduction%2F4118c464c91cac07eea3aa2924640835dcd2e5c9-600x600.webp%3Fw%3D64%26h%3D64%26fit%3Dcrop%26auto%3Dformat&w=64&q=75)Plain Greek Yogurt](/learn/food/plain-greek-yogurt) ## Development milestones - [6-9 months](/learn/milestones/6-9-months) [← All solids guides](/learn/solids) [Read as Markdown](/api/markdown?path=%2Flearn%2Fsolids%2Fallergen-introduction)