What is an allergy food?

An allergy food is a type of food that is harmless to most people but triggers an allergic reaction in some people.

If you have a food allergy, when you come in contact with the food that you’re allergic to, your immune system reacts to it and causes the symptoms of an allergic reaction.

The most common foods that cause allergic reactions are:

• eggs
• cow's milk
• peanuts
• tree nuts (almonds, Brazil nuts, cashew nuts, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts)
• sesame
• soy
• shellfish (including prawns, crab and lobster)
• fish
• wheat
• lupin

Are food allergy and food intolerance the same?

Food allergies and food intolerance are not the same.

An allergy involves the body's immune system and can be serious. An intolerance is a reaction that doesn’t involve the immune system. If you have a food intolerance, you may experience unpleasant symptoms after eating the problem food, but you will not have a dangerous reaction.

A doctor can arrange allergy tests to diagnose food allergies. Food intolerances will not show up on these tests.

How common are food allergies?

Food allergies affect about 1 to 2 in every 20 children. Allergic diseases, including food allergies, have increased in recent years. It’s not fully understood why.

Babies are more likely to develop allergies if there’s a family history of allergic diseases such as eczema, asthma, hayfever or food allergies (known together as ‘atopy’).

Babies with no family history of atopy can also develop allergies, so the recommendations for introducing solids are the same for all families, including families where a parent or sibling has an allergy.

If you already know your baby has an allergic disease, such as severe eczema or food allergy, talk to your doctor before introducing solids.

When should I start giving my baby allergy foods?

You can introduce allergy foods to your baby when you are introducing solids. This is usually from around 6 months of age, but not before your baby is 4 months old. Introduce common allergy foods before your baby reaches 12 months of age, since this may reduce their chance of developing an allergy.

If possible, continue to breastfeed while you are introducing solids, since this may reduce the risk of allergies developing.

If you’re not breastfeeding, you can give your baby a standard cow’s milk based formula. Do not give your baby special hydrolysed infant formula or soy or goat’s milk formula to try to prevent allergy.

The first foods you give your baby should be foods that your family usually eats, even if they are common allergy foods. Try to include foods that contain iron in your baby’s diet. The Infant Feeding and Allergy Prevention Guidelines have been developed by the Australasian Society of Clinical Immunology and Allergy to help guide parents and health professionals on how and when to introduce allergy foods.

Which allergy foods should I introduce first?

Start with the allergy food you would like your baby to try first. Remember that the food should be age-appropriate (smooth, soft foods to start with, then moving to foods with different textures as your baby grows).

A good place to start is with soft foods like a well-cooked egg or smooth peanut butter. Don’t give your baby whole or chopped nuts, since this could cause choking.

How should I introduce allergy foods?

It’s best to try one new allergy food at a time. That way, if your baby has an allergic reaction, it will be easier to identify which food is causing the reaction.

If your baby doesn’t have an allergic reaction to the new food, keep giving it to them about twice a week. An allergy may develop if the food isn’t given on a regular basis after trying it. Mix a small amount of the new food in with your baby’s usual food. If your baby doesn’t have a reaction, you can gradually increase the amount next time.

You can try a new allergy food each day — but remember to keep giving your baby the food once you have introduced it to their regular diet.

If you want to test a type of food before your baby eats it, rub a small amount of the food on the inside of your baby’s lip. If there is no reaction after a few minutes, then your baby can try eating it. Don’t rub food on your baby’s skin. This will not show whether your baby will have an allergic reaction to it.

What time of day should I introduce allergy foods?

Try introducing new allergy foods during daytime meals. That way, if your baby has a reaction, you can monitor them more easily.

What can I do to prevent my baby having a food allergy?

There’s no known way to completely prevent allergies, but there are some things you can do that may lower your baby’s risk:

• Introduce solids from 6 months of age.
• Introduce common allergy foods before your baby turns one.
• If possible, breastfeed your baby until they are at least 6 months old and continue while introducing solids.
• Let your baby get dirty when they play, to expose them to ‘good’ germs.
• Give your baby some safe sun exposure to increase their vitamin D levels.

How can I tell if my baby is having an allergic reaction?

Symptoms of an allergic reaction usually occur within a few minutes, but can take up to 2 hours to develop.

Mild-to-moderate symptoms may include:

• hives or red welts (bumps) on the skin
• swelling of the lips, face or eyelids
• tingling in or around the mouth
• stomach pains
• vomiting
• diarrhoea

If your baby has redness around their mouth, it’s usually not an allergic reaction. Babies have sensitive skin that can be irritated by contact with some foods. If you’re concerned, it’s best to discuss this with your doctor.

More serious symptoms can indicate a severe allergic reaction, known as anaphylaxis. Anaphylaxis is rare, but it is a medical emergency. The symptoms of anaphylaxis may include:

• difficulty breathing or noisy breathing
• swelling of the tongue
• swelling of the throat — this can cause drooling
• hoarse voice
• cough or wheeze
• looking pale
• collapse or going 'floppy'

What should I do if my baby has an allergic reaction?

Anaphylaxis

• Call triple-zero (000) and ask for an ambulance.
• If your baby has an injection device containing adrenaline, such as EpiPen Jr or Anapen Junior, give them the injection immediately and call the ambulance.
• Lay your baby flat while waiting for the ambulance.
• Your baby can sit if they are having trouble breathing.
• Lay your baby on their side if they’re unconscious or vomiting.

Mild or moderate allergic reaction If your baby has a mild reaction to a certain type of food:

• Stop giving them that food.
• Monitor them for symptoms of anaphylaxis.
• See your doctor for advice and an accurate diagnosis.

What should I do if my baby is diagnosed with a food allergy?

See your doctor for advice and an action plan with instructions about how to treat an allergic reaction if it happens again.

Your doctor might refer you to an allergy specialist who may arrange allergy tests. These tests are specialised and must be interpreted by a specialist doctor. True food allergies can be serious. An accurate diagnosis is important.

Be aware that your baby could have a more serious reaction the second time they’re exposed to the food they’re allergic to.

Don’t be tempted to experiment by cutting out a major food, such as milk or wheat, without guidance from a health professional. This could lead to your child not getting the nutrients they need.

If your child needs to avoid certain foods, you can speak with a dietitian to make sure your baby still gets everything they need for their growth and development.

Will my baby grow out of their food allergy?

Many children grow out of some food allergies, although others may continue to be affected throughout their life.

Most children will outgrow allergies to milk, soy, wheat or eggs. Allergies to peanuts, tree nuts, sesame and seafood are most likely to last for life.

Resources and support

Speak to your doctor or child health nurse for more information on allergy foods.

'Nip Allergies in the Bub' is an initiative from the National Allergy Strategy that has information for both parents and health professionals.

Learn more about allergies from the Australasian Society of Clinical Immunology and Allergy.

Read more about avoiding food allergies in babies from the Royal Australian College of General Practitioners.