Early Egg Introduction Cuts Childhood Egg Allergy

Building on the LEAP and EAT studies

This new evidence stems from  Prof. Lack’s ground-breaking LEAP (Learning Early About Peanut) study in 2015. This showed that introducing peanut early reduced peanut allergy by more than 80% in the children studied. The EAT (Enquiring About Tolerance) study and trials in Japan and elsewhere went on to show a similar protective effect for egg and other foods. Together, this body of evidence overturned decades of advice that had told parents to delay allergenic foods, and it prompted countries around the world to update their infant feeding guidelines.

Australia acted quickly. Following the LEAP results, it updated its national guidance in 2016 to recommend introducing egg and other allergenic foods in the first year of life. What Dr Koplin’s  new study demonstrates is that this change in policy was followed by a real change in behaviour, and that the change in behaviour was followed by a measurable fall in allergy. In other words, the chain runs all the way from a clinical trial, to a guideline, to the diets of ordinary babies, to fewer children growing up with egg allergy.

The same pattern is now emerging with early introduction of other foods. In the United States, rates of both peanut allergy and overall food allergy have also declined since infant feeding guidelines shifted towards earlier introduction of allergenic foods. In Australia, earlier peanut introduction following changes to national feeding advice was accompanied by a fall in peanut allergy. These real-world observations reinforce the message of studies such as LEAP and EAT: introducing allergenic foods at the right time can alter the trajectory of food allergy, not just for individual children, but across entire populations. This is precisely the kind of impact we hoped our research would have when we set out to challenge the old advice. Controlled trials such as LEAP and EAT can show a reduction in allergy of 80 to 90% under ideal conditions. This study shows that even when a guideline is rolled out across a whole population, with all the variation of real family life, it still produces a measurable benefit.

The effect was greatest in babies with eczema

One of the most important details in the study concerns babies with early eczema. In this group, egg allergy fell by 37%, from 34.6% to 21.9%, a far larger drop than in the population as a whole.

This matters because babies with eczema are at the highest risk of developing food allergy in the first place. As we explain in our guidance on food allergy risk, a compromised skin barrier can allow food proteins to reach the immune system through inflamed skin rather than through the gut, which can lead to allergy. The fact that early egg introduction made the biggest difference in exactly this high-risk group is strong support for the dual allergen exposure hypothesis developed by Professor Lack.

It would be a mistake, though, to think of early introduction as something only for high-risk babies. While the protective effect is largest in infants with eczema, most food allergy across the population occurs in children without severe eczema. That is why the case for early introduction applies to all babies: advice aimed only at the highest-risk infants would miss the majority of cases. This is a population-wide opportunity, not a niche measure.

What about other foods

The benefits of early food introduction appears to extend beyond egg. A large US study found that after national guidelines encouraged the early introduction of allergenic foods, peanut allergy fell by 43%, accompanied by a reduction in overall food allergies by 29%. While peanut has the strongest evidence base, these real-world findings support the broader strategy of introducing a variety of allergenic foods during infancy to promote immune tolerance.

Earlier is better

A consistent theme runs through all of the science, and it is worth stating plainly. The clear message from the research is that earlier is better, and this applies to peanut, egg, and probably most food allergens.

Australian data on peanut showed that after national guidelines changed to encourage earlier peanut introduction, peanut allergy fell from 3.1% to 2.6%. The study also found a clear trend: babies introduced to peanut from four to six months of age were better protected than those first introduced peanut later. In other words, it is not just whether peanut is introduced that matters, but when it is introduced. Introducing foods early, particularly during the first few months of weaning, appears to provide the greatest protection against allergies.

What parents can do

The practical steps are straightforward, and for most low-risk babies they can be taken safely at home. The key is that early introduction is a managed process, not a free-for-all: it means giving the correct amounts of the right foods, prepared in a safe form, regularly over time, and seeking professional guidance first if your baby is at higher risk. Done this way, it is both safe and effective.

• Introduce egg and peanut early. Once weaning has begun, from around four to six months, well-cooked egg and smooth peanut butter or peanut puff snacks can be introduced. These should be prepared in an age-appropriate way. For example, never give whole nuts to babies and young children, as these are a choking hazard.
• Keep them in the diet regularly. Timing is only half the picture, as regularity matters just as much. Early introduction works best when these foods are given a few times a week, and kept in the diet through the first years of life, rather than offered once and then dropped.
• Give adequate amounts of the food. Studies suggest that allergy prevention depends not only on introducing foods early, but also on consuming enough of them. Examples include 1 whole well cooked egg per week, or 2-4 teaspoonfuls of smooth peanut butter per week. Small tastes given occasionally are unlikely to have the same effect as regular, ongoing consumption of appropriate portions of the food. 

The exact amount varies between foods and between studies, but the principle is the same: early introduction works best when appropriate amounts of the foods are eaten regularly and become part of normal family life, rather than being given occasionally.

• Treat eczema properly. Effective, proactive eczema care helps protect the skin barrier and is an important part of allergy prevention in its own right.
• Seek advice if your baby is high risk. If your baby has early-onset moderate or severe eczema, or has already developed a food allergy, speak with a specialist before introducing peanut, as some children may benefit from supervised introduction or testing first.

What about breastfeeding?

Parents sometimes worry that early introduction of solids means giving up on breastfeeding. It does not. Breastfeeding is always recommended and is entirely compatible with introducing healthy solid foods early.

In the EAT study, where babies were encouraged both to breastfeed and to eat solids from around three months of age, breastfeeding rates remained high all the way through to twelve months. The two go hand in hand.

A simple practical tip is to mix small amounts of new foods, such as well-cooked egg, smooth peanut butter, fruit or vegetables, with expressed breast milk. The familiar taste and smell of breast milk can make new foods more acceptable and may help babies transition more easily as they begin weaning.‍

Looking ahead

This study is a reminder that food allergy is, in many cases, preventable, and that prevention can work not only for individual families but at the level of whole populations.

If your baby has reached four to six months of age, introducing egg and peanut, on a regular, frequent basis will help protect against egg and peanut allergy.

Every child's allergy journey is different. Whether you are looking for advice on how to safely and effectively introduce allergenic foods, a prevention plan for a high-risk baby, or a diagnosis, consult your specialist team to help you find the right path forward.

Frequently Asked Questions

When should I introduce egg to my baby?

For most babies, suitably prepared well-cooked egg can be introduced once weaning has begun, from around four to six months of age, and then kept in the diet regularly. If your baby has early or severe eczema, speak with a specialist before introducing peanut.

Does introducing egg early really prevent egg allergy?

The evidence is now strong. Controlled trials showed that early introduction reduces allergy. Now a 2026 study confirms that when Australian guidelines changed and more parents gave egg early, egg allergy across the whole population fell by more than 17%.‍

My baby has eczema. Is early introduction safe?‍

Yes. Babies with eczema have the most to gain from early introduction, as they are at higher risk of developing food allergy. However, babies with moderate or severe eczema are also more likely to already have a food allergy. If this applies to your baby, or they are over 6 months of age and have not yet started allergenic foods, speak to your GP or an allergy specialist.

Can I still breastfeed if I introduce solids early?

Yes. Breastfeeding and early introduction of solid foods are entirely compatible, and we recommend both.