Paediatric Dietitian and Nutritionist, and founder of Nourishing Bubs, Olivia Bates on introducing food allergens to your baby’s diet, and her new Allergen Packs that make it easy.

Any food can be considered a potential allergen but when referring to the ‘allergens’, we are talking about the foods responsible for 90% of allergies worldwide. By law, these foods have to be called out on food packaging and are highlighted under the list of ingredients with a ‘contains’ statement. They are also in bold on the ingredient list.

In Australia, we follow guidelines set out by the Australian Society of Clinical Immunology and Allergy (ASCIA) on how and when to introduce the allergens. It is recommended to introduce the allergens at around 6 months (not before 4 months) when your baby starts consuming solid foods. They should be introduced one at a time, mixed into a previously tolerated food and starting with a small amount (1/4 tsp) on the first exposure. Provided there is no reaction on the first exposure, the amount should be increased to ½ teaspoon on the second exposure and 1 teaspoon on the third exposure. The three exposures can occur over three consecutive days or within one week. I find it easier to aim to introduce one allergen per week, which will give you time to introduce all the allergens by the time your little one is 12 months, allowing for weeks off due to sickness/holidays etc.

Always make sure you introduce the allergen in an age appropriate format, so for example no whole nuts as they are a choking hazard. Eggs can be introduced by mashing a hard-boiled egg (making sure to include the yolk and white) and then taking ¼ tsp and mixing into previously tolerated foods. Nuts should be introduced as a ground nut (as is found in the Nourishing Bubs Allergen Intro Pack) or as a nut butter. You may need to thin butters out with hot water as large globs of nut butter can also be a choking hazard.

Once your little one has passed the 3 initial exposures, you should aim to offer 1 teaspoon twice weekly, of each allergen to maintain your baby’s tolerance. Once at this maintenance stage, it is not necessary to offer each one individually.

The Order of Introduction

There is no hard and fast rule with regards to the order in which you introduce the allergens, however the most evidence and guidance is around egg, peanut and milk. If your child is on a cow’s milk-based formula, this would count as their introduction to cow’s milk. Current recommendations advise introduction of the common allergens along with complementary foods ~6 months (and not before 4 months).

Generally, egg and peanut (as well as cow’s milk) are encouraged earlier (closer to 6 months) however this is largely because there is the most evidence relating to these. While there is little guidance with regards to the other allergens, the mechanism of sensitisation is thought to be similar and therefore it is generally considered there is no harm in early introduction. Consequently, current guidelines agree that all potential food allergens should be introduced by a child’s first birthday. From a practicality point of view, it is best to introduce the foods in the order in which they are consumed within your household, i.e. those foods which are more readily consumed, should be prioritised over those less frequently eaten. Increasing evidence is also supporting the need to continue to offer these foods, at least weekly, provided they are tolerated, in order to maintain tolerance.

Predispositions That Make Allergies More Likely

Certain factors can increase the risk of food allergies in infants, requiring families to be extra cautious when introducing allergens. A family history of allergies, including food allergies, asthma, eczema, or hay fever, puts them at higher risk of developing a food allergy, although the precise mechanism is still very much an area of research. Babies with moderate to severe eczema are at significant risk, as are those who have already shown sensitivity to other foods. Conditions such as colic or reflux may sometimes indicate underlying food intolerances, though they are not direct causes of allergies.

While, the guidelines to introduce all allergens before 12 months remains the same for those families who have a higher risk child, you may wish to discuss allergen introduction with your GP or paediatrician before you start incorporating allergens into your little one’s diet.

How to Know If Your Baby Is Allergic to a Food

Allergic reactions usually take place within minutes, up to 2 hours after a food is ingested. Allergic reactions are considered either mild to moderate or severe (anaphylaxis). A mild to moderate reaction may include hives or welts, vomiting, significant changes in wellbeing or swelling of the lips, eyes or face.

A more severe reaction, known as anaphylaxis, may involve wheezing or persistent cough, difficulty breathing, swelling of the tongue, swelling in throat, change in voice or cry and/or pale and floppy/collapsing.

If you notice any of the above signs that suggest your child may be having an allergic reaction, stop feeding the food immediately and seek medical attention. If they are showing signs of a mild reaction, continue to monitor for signs of a severe reaction. You may wish to take your child to the doctor immediately, otherwise take photos of the reaction and make the next available appointment with the doctor. Do not offer that allergen again until you have discussed the reaction with the doctor and made a plan for follow up introduction.

If your child is having a severe reaction, lay them flat in your arms. DO NOT allow them to walk or stand upright and call 000 immediately.

Confirming an Allergy

If you suspect your child has a food allergy, the first port of call will be a check in with a GP who will ultimately likely send you to your paediatrician or an allergist. Allergies are complex and still not an exact science which is why the government is investing so much into research around allergies. One of the main issues can be determining whether it is a true allergy or more of a sensitivity/intolerance. Diagnosing a food allergy involves several steps, and working with a doctor or allergist can help you get clear answers.

The process usually starts with a detailed medical history. Your doctor will ask about your child’s symptoms—what they ate, how long it took for a reaction to appear, and whether it happens every time. Keeping a food diary can be really helpful (and something I would recommend when starting solids), as it allows you to track patterns (changes to sleep, stools and any other symptoms such as rashes or changes in bub’s wellbeing) and pinpoint possible triggers. Sometimes, doctors suggest an elimination diet, where the suspected food is removed for a few weeks. This is also why when commencing solids, starting with single foods or one new food a day can be helpful as you then don’t need to do an elimination diet in the future, which can be cumbersome. If symptoms improve and then return when the food is reintroduced, that’s a strong clue.

Next, your child may need allergy tests. The two most common are the skin prick test and the IgE blood test, both of which measure the body’s allergic response to specific foods. However, these tests aren’t perfect and are not ideal for young children.

The gold standard for confirming a food allergy is the oral food challenge. This is done under strict medical supervision, where your child eats small amounts of the suspected allergen while doctors monitor for reactions. It’s the most accurate way to know for sure, but it’s only done when absolutely necessary and in a controlled setting.

Life with a Child With an Allergy

Having a child with an allergy changes your daily routine in a big way. Every meal requires extra planning as you will need to constantly check labels, and make sure there’s no risk of cross-contamination. School and social events can be extra difficult and will require additional coordination, from informing teachers and caregivers to packing allergy-friendly snacks so your child doesn’t feel left out. You also have to be prepared for emergencies, always carrying epi-pen or antihistamines, just in case.

Beyond the logistics, allergies can take an emotional toll too. Kids might feel different or left out when they can’t eat what their friends are having, so it’s important to teach them how to advocate for themselves and help them feel included. The good news is that some allergies, like milk, eggs, soy, and wheat, can be outgrown, while others—like peanuts, tree nuts, and shellfish—are more likely to stick around for life. If you suspect your child has outgrown an allergy, don’t test it at home! The safest way to find out is through an allergist, who can do skin prick tests, blood tests, or even a supervised oral food challenge. If your child has an allergy, life takes a little extra planning, but with the right precautions, they can still enjoy all the things kids love—just with a little extra care. There are also some great resources available through Allergy and Anaphylaxis Australia which is a charity that provides allergy support.

Allergy Misconceptions

One of the biggest misconceptions is that allergies and food intolerances are the same thing. This is not the case. An allergy involves the immune system and can be life threatening while intolerances such as a lactose intolerance, generally involve digestive systems such as bloating, flatulence and diarrhea. While these symptoms are uncomfortable, they are not life threatening.

Another misconception is that all childhood allergies can be outgrown however this is not the case for all children or all allergies. Some allergies such as those to milk, soy, wheat and egg can be outgrown, others like peanuts, tree nuts and shellfish tend to be lifelong.

Yet another one, which can be very dangerous, is the misconception that if you have previously had a mild reaction, you won’t have a severe one. Allergies are still very much misunderstood and unpredictable. Just because someone has only had a mild reaction in the past, doesn’t mean they won’t have a severe, even anaphylactic reaction in the future. This is why it is important to discuss any allergic reactions with your doctor.