What is allergen introduction?

Allergen introduction means offering foods that commonly cause allergies, such as egg and peanut, from around 6 months as part of starting solids. Each one is introduced on its own so that any reaction can be traced, and, if tolerated, kept in the baby's diet.

Key takeaways

• The NHS advises not delaying egg and peanut beyond 6 to 12 months, as later introduction may raise the risk of allergy.
• Introduce allergenic foods one at a time.
• Once a food is tolerated, keep offering it regularly.

How should allergenic foods be introduced?

Offer one new allergenic food at a time, in a form that is safe for a baby: well-cooked egg, smooth peanut butter mixed into food, or finely ground nuts rather than whole nuts. Many families leave two to three days between new allergenic foods so that any reaction is easier to link to the right food. Common allergenic foods include cows' milk, egg, peanut and tree nuts, wheat, soya, sesame, fish and shellfish.

What does a reaction look like?

According to the NHS, reactions usually start within minutes, although they can take up to 2 hours, and up to 3 days for cows' milk. Signs include a red, itchy rash, swelling of the lips or face, vomiting, worsening eczema and wheezing.

What you can do

• Introduce new allergenic foods earlier in the day, when you can watch your baby afterwards.
• Keep tolerated allergens in the menu a few times a week.
• If your baby has severe eczema or a known food allergy, talk to your doctor before introducing allergens.