Allergen Introduction for Babies: The Complete LEAP Guide for Parents

⚠️ IMPORTANT MEDICAL DISCLAIMER: This content is for informational purposes only and does not constitute medical advice. Allergen introduction carries real risks for high-risk infants. Always consult your child's GP or paediatrician before introducing allergens, especially if your baby has severe eczema, an existing food allergy, or a strong family history of allergies.

The Research That Changed Everything: The LEAP Study

The LEAP (Learning Early About Peanut Allergy) study - one of the most influential food allergy studies ever conducted - found that early introduction of peanuts to high-risk infants reduced peanut allergy risk by over 80%. The old advice to delay peanuts was not only unhelpful - it was actively counterproductive.

Following LEAP and subsequent research, the American Academy of Pediatrics (AAP) - and NHS guidance - now recommends introducing allergenic foods early, around 4 to 6 months, when solids begin. The major allergens are: peanuts, eggs, tree nuts, fish, dairy, wheat, and sesame.

The fundamental principle: early, repeated exposure teaches the immune system to recognise a food as safe rather than react to it.

Is My Baby High-Risk? What to Consider Before Starting

Most babies can begin allergen introduction at home following the guidelines below. However, some babies need medical guidance first:

• Severe eczema (especially in early months): Babies with persistent, severe eczema have an elevated risk of peanut allergy. Their introduction should be guided by a paediatrician or allergy specialist.
• Existing food allergy: If your baby has already reacted to any food, consult a specialist before introducing additional allergens.
• Strong family history: If one or both parents have multiple severe food allergies, discuss with your GP first.

For mild to moderate, well-controlled eczema, current guidelines support home introduction with standard precautions. When in doubt, check with your health visitor or GP.

Step-by-Step Allergen Introduction Schedule

When to Start

• Around 4–6 months, when you begin introducing solid foods
• Baby should be well on introduction day - no fever, no active illness
• Introduce in the morning or early afternoon - not before bedtime - so you can observe for reactions during waking hours

The 3-Day Rule

Introduce one new allergen at a time and wait at least 3 days before introducing the next. This allows you to identify which food caused a reaction if one occurs.

Allergens to Introduce

• Peanut: Thinned smooth peanut butter mixed into purée. Never give whole peanuts to babies (choking hazard).
• Egg: Well-cooked scrambled egg or egg mixed into food. Start with a very small amount.
• Tree nuts: Ground or as smooth butters - never whole.
• Fish: Well-cooked, boneless, flaked into purée. Low-mercury fish (salmon, cod) are good starting choices.
• Dairy: Plain yogurt or soft cheese (whole cow's milk as a drink is not recommended before 12 months, but dairy in foods is fine earlier).
• Wheat: Wheat-containing cereal or bread mixed into purée.
• Sesame: Tahini thinned and mixed into purée or other foods.

How Much to Give

Start with approximately 1/4 teaspoon. If no reaction occurs after 10–15 minutes, give a slightly larger amount. Gradually increase over the following days and weeks toward age-appropriate servings.

Signs of an Allergic Reaction

Mild signs (monitor carefully, call NHS 111 if unsure):

• Small hives around the mouth or face
• Mild redness or rash
• Mild sneezing or runny nose

Call 999 or go to A&E immediately if you see:

• Hives spreading across the body
• Swelling of the lips, tongue, or throat
• Difficulty breathing or wheezing
• Vomiting combined with other symptoms
• Collapse or extreme pallor

These are signs of anaphylaxis - a medical emergency. If in any doubt, call 999 immediately.

The Importance of Continued Exposure

Research shows that ongoing regular exposure is as important as the first introduction. Once you have successfully introduced an allergen, continue offering it several times a week to maintain the immune system's tolerance.

[LINK: allergen-friendly baby and toddler recipes]

--- **Disclaimer:** This guide is for informational purposes only and does not constitute medical or nutritional advice. Allergen information is a general guide only - cross-contamination in home kitchens cannot be guaranteed. Always consult a qualified allergist or healthcare provider before dietary changes. pashutFree is not liable for adverse health events resulting from use of this content.