Introducing allergens to your baby: the UK approach
How UK guidance suggests introducing the common food allergens from around six months, one at a time, and what to watch for as you build up your baby's diet.
Weaning is an exciting stage, and one of the questions parents ask most is when and how to introduce the common food allergens. Current UK advice has shifted the thinking here, so it is worth understanding the approach rather than relying on what was recommended a generation ago. This is general information to help you feel prepared, not medical advice for your individual baby.
Start from around six months, alongside other foods
UK guidance suggests introducing the common allergens from around six months, as part of your baby’s wider move onto solid foods, once they are showing the usual signs of being ready to wean. Importantly, current advice is that there is no benefit in deliberately holding these foods back. Delaying their introduction does not appear to reduce the chance of an allergy developing, so they can sit alongside the other new tastes you are offering.
The common allergens to introduce as part of a varied diet include foods such as well-cooked egg, smooth peanut in an age-appropriate form, dairy, wheat, fish and the other allergens named in UK law. They should always be given in a texture suitable for a baby, never as whole nuts or pieces that could cause choking.
Introduce one at a time, and keep offering
The single most useful habit is to introduce each new allergen on its own. Offer one new allergen, then wait a few days before introducing the next. If a reaction does happen, you will have a much clearer idea of what caused it than if several new foods went in together.
Just as important, keep offering the foods your baby tolerates. Introducing an allergen once and then dropping it is not the goal. Building these foods into your baby’s regular diet, so they keep eating them, is the approach UK guidance encourages. A first taste is the beginning, not the test.
Pick a calm time of day for a new allergen rather than the end of a tired evening, and offer a small amount first. This is not about being anxious, it is simply about being able to watch your baby comfortably as they try something new.
What to watch for, and when to seek advice
Most babies take new foods in their stride. When you do introduce an allergen, keep a relaxed eye out for signs such as redness or a rash around the mouth, hives, swelling, tummy upset or a change in how your baby seems. Mild reactions are not unusual and do not always mean a lasting allergy, but they are worth noting.
If you think your baby has reacted to a food, stop offering it and speak to your GP or health visitor, who can advise on what to do next before you try it again. If there are ever signs of a serious reaction, such as difficulty breathing, swelling of the face, lips or tongue, or your baby becoming floppy or seriously unwell, treat it as an emergency and call 999. This guidance is not a substitute for that professional support.
If your family already has a strong history of allergies, or your baby has eczema, it is worth talking to your health visitor or GP before you start, as they may suggest a slightly different plan tailored to your baby.
Introducing allergens steadily, one at a time, and keeping the safe ones in the diet is the calm, evidence-led approach UK guidance points to. As your baby grows into packaged foods, read every label carefully and use The Food Allergy Lab to check the hidden names an allergen can hide behind.
Get the free Allergen Label Decoder
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Common questions
When should I introduce common allergens to my baby?
UK guidance suggests introducing the common allergens from around six months, alongside other solid foods, once your baby is showing signs of being ready for weaning. There is no need to leave them until later, and delaying does not appear to help.
Should I introduce allergens one at a time?
Yes, introducing each new allergen on its own, with a few days before the next one, makes it much easier to tell what caused a reaction if one happens. Keep offering the foods your baby tolerates as a regular part of their diet rather than trying once and stopping.
What should I do if my baby reacts to a new food?
Stop offering that food and speak to your GP or health visitor for advice before reintroducing it. If your baby ever has trouble breathing, swelling of the face or lips, or seems seriously unwell, treat it as an emergency and call 999.