Allergen introduction
Whether and when to give common allergy-causing foods such as peanut and egg to your baby, and how to keep offering them.
When should we introduce peanut, egg and other allergens?
In short: Parents choose between 3 main approaches: Early and deliberate (peanut and egg from 4-6 months, then weekly); Around 6 months with other solids; Delay. Evidence: well established. Guidance and evidence agree. The real question is whether you'll follow it. Best settled: 0–6 months.
- Evidence
- Well established
- Best settled
- 0–6 months
- Part of
- Pregnancy to first birthday
Allergen introduction: what are the options?
Parents usually land on one of these 3 approaches.
1. Early and deliberate (peanut and egg from 4-6 months, then weekly)
You give peanut and egg early and keep giving them regularly.
2. Around 6 months with other solids
You introduce allergy-causing foods along with other first foods at about six months.
3. Delay
You hold off on allergy-causing foods until later.
Allergen introduction: what does the evidence say?
Well established. Guidance and evidence agree. The real question is whether you'll follow it.
The LEAP trial gave 640 infants with severe eczema, egg allergy or both either peanut or none until age 5, and early peanut cut peanut allergy by 81%. The 2017 US guidance (NIAID) advises that babies with severe eczema or egg allergy be evaluated by a clinician before peanut is introduced, from 4-6 months, while US and Canadian allergists now advise peanut and cooked egg around 6 months for all babies. An October 2025 Pediatrics study reported peanut allergy falling from 0.79% to 0.45% of children after the guidelines changed, and all food allergies from 1.46% to 0.93%
Sources
What else is worth knowing?
Advice has reversed in recent years: introducing foods such as peanut and egg early is now thought to help prevent allergy. Babies with severe eczema or an existing allergy may need medical advice first. Once introduced, the food needs to stay in the diet.
Questions to ask each other
- What do we know about when and how to introduce peanut and egg?
- Does anyone in either family have allergies, and should that change our plan?
- Who will ask the pediatrician before we start?
More in Feeding the baby
First published 2026-10-03. Last updated 2026-10-05. General information, not medical advice.