How to introduce allergens to your baby safely

In short

From around six months, once your baby is ready for solids, introduce common allergens — including peanut and egg — one at a time, in an age-appropriate form, leaving a couple of days before the next new one. Current UK advice is not to delay allergens, even if your baby has eczema or a family history of allergy; if they have severe eczema or an existing food allergy, ask your GP or health visitor first.

Key takeaways

• Start common allergens from around six months, alongside other first foods — not before.
• Introduce one new allergen at a time so any reaction is easy to link to a food.
• Do not delay allergens: introducing peanut and egg early may reduce the risk of allergy.
• If your baby has severe eczema or an existing food allergy, speak to your GP before starting.

When to start

Common allergens can be introduced from around six months, once your baby shows the signs of being ready for solids — sitting up well with good head control, reaching for food, and being able to swallow rather than push food back out. There is no benefit to introducing solids before this point, but there is also no reason to hold allergens back once weaning is under way.

Introduce one allergen at a time

Offer a single new allergen on its own, in a small amount and an age-appropriate texture, ideally earlier in the day so you can watch your baby over the following hours. Wait a couple of days before introducing the next new allergen. Mixing several new foods at once makes it hard to know which one caused a reaction if one happens.

• Peanut — smooth peanut butter thinned into a purée, or a peanut puff softened. Never whole nuts (a choking hazard).
• Egg — well-cooked, mashed or blended into food.
• Dairy — full-fat yoghurt or cheese, or milk used in cooking (not cow’s milk as a main drink under one year).
• Then work through the others over time: wheat, soya, fish, shellfish, sesame, tree nuts (as smooth butters), and seeds.

Babies with eczema or a family history

Babies with eczema, or with a parent or sibling who has a food allergy, are more likely to have a food allergy themselves — but current UK advice is still to introduce allergens early rather than to delay them, as delaying does not reduce the risk and may increase it. If your baby has severe eczema or has already reacted to a food, speak to your GP or health visitor before introducing peanut and egg, as they may suggest doing so with extra care.

Keep going once introduced

Once an allergen has been introduced without a reaction, keep it as a regular part of your baby’s diet — roughly a couple of times a week — rather than offering it once and stopping. Regular exposure helps maintain tolerance.

Logging which allergen you introduced on which day in VitaBaby — alongside feeds and any notes — gives you a clear record to look back on if you ever need to work out whether a food triggered a reaction.

FAQ

Sources

• Food allergies in babies and young children — NHS
• Weaning and food allergy prevention — British Society for Allergy & Clinical Immunology (BSACI)
• Weaning your baby — Allergy UK

Related guides

• Signs of a food allergy in babies and toddlers
• Cow’s milk protein allergy and slow weight gain
• Weaning a baby with food allergies