Allergenic foods: when and how to introduce them
Eggs, peanuts, milk, fish: how and when to safely introduce allergenic foods during weaning.
Allergenic foods: when and how to introduce them
For years, people believed that delaying the introduction of allergenic foods would reduce the risk of allergies. Today we know the opposite is true: introducing them early can actually be protective.
What does current research say?
The most important studies (LEAP, EAT) have shown that early introduction of allergens — from 6 months — can reduce the risk of developing allergies by up to 80%.
The main food allergens
- Cow's milk (as an ingredient, not as a drink)
- Eggs (starting with well-cooked yolk)
- Peanuts (as butter or paste, never whole due to choking risk)
- Tree nuts (as flour or butter)
- Fish
- Shellfish and mollusks
- Wheat
- Soy
- Sesame
How to introduce them safely
The basic rule
Introduce one allergen at a time, in small amounts, and wait 3-5 days before trying another. This allows you to easily identify the cause if a reaction occurs.
The first time
- Give the first serving in the morning or at lunch (so you have time to watch for any reactions)
- Start with a very small amount (half a teaspoon)
- Gradually increase the amount over the following days
- Do not introduce more than one new allergen on the same day
A practical example: eggs
- Day 1: one teaspoon of well-cooked hard-boiled yolk, mixed into the meal
- Days 2-4: watch for any reactions
- Day 5: increase the amount
- After 1-2 weeks: try the whole egg (yolk + white), well cooked
How to recognize an allergic reaction
Mild reactions (within 2 hours)
- Redness around the mouth
- Localized hives (raised red bumps)
- Slight swelling of the lips
- Vomiting
Severe reactions (anaphylaxis) — call emergency services
- Difficulty breathing
- Swelling of the face, tongue, or throat
- Sudden paleness
- Loss of consciousness
Children at higher risk
If your child has:
- Moderate-to-severe eczema
- A previously diagnosed food allergy
- A family history of allergies (allergic parents or siblings)
Talk to your pediatrician or allergist before starting. Testing before introduction may be recommended.
The role of your pediatrician
Your pediatrician is your go-to resource. Always consult them before introducing allergens if your child has eczema, if there is a family history of allergies, or if you have any concerns at all.
Introducing allergens early and gradually is the best way to protect your child. Do it with confidence and with your pediatrician's support.
