Food allergies in babies: an Australian guide

Food allergy is one of the most anxious parts of starting solids. It is also one of the areas where Australian guidance has changed significantly. The old advice was to delay allergenic foods. The current advice is the opposite: introduce them early, keep them in the diet if tolerated, and get specialist advice for babies at higher risk.

This guide covers the practical steps, the signs to watch for and what to do if something goes wrong. It is general information, not a substitute for an individual allergy plan.

What is a food allergy?#

A food allergy is an immune system reaction to a protein in a food. Symptoms can affect the skin, gut, breathing and circulation. Reactions usually happen within minutes to two hours of eating the food, although some delayed reactions can take longer.

Many food allergies in babies are IgE-mediated, meaning the immune system releases histamine and other chemicals quickly. These are the reactions that can cause hives, swelling and anaphylaxis. Non-IgE reactions tend to be delayed and mainly affect the gut, such as vomiting or blood in the stool.

Food allergy is different from food intolerance. Intolerance does not involve the same immune response and is not life-threatening, although it can make a child uncomfortable. Cow's milk is the classic example: a milk protein allergy and lactose intolerance cause overlapping symptoms but need different treatment. Our cow's milk allergy and lactose intolerance guide explains the difference.

The common allergens#

In Australia, the common food allergens are:

• egg
• peanut
• cow's milk
• wheat
• soy
• fish
• shellfish
• sesame
• other tree nuts

These foods should be introduced in an age-appropriate form. For example:

• well-cooked egg, mashed or as soft strips
• smooth peanut butter thinned with water or milk, or spread thinly on toast
• full-fat cow's milk yoghurt or cheese
• wheat-based toast, pasta or cereal
• smooth tofu or soy yoghurt
• flaked fish with bones removed
• well-cooked prawn, finely chopped
• tahini or sesame paste thinned into a soft food
• smooth tree nut butter or finely ground nuts

Do not give whole nuts, thick globs of nut butter or hard pieces of food to a baby. They are choking hazards.

How to introduce allergens#

Current Australian guidance from ASCIA recommends introducing common allergens around six months and before 12 months, rather than delaying them. This applies to all babies, including those with eczema and a family history of allergy.

A practical approach:

1. Start when your baby is well. Avoid introducing a new allergen during illness, teething or a big routine change.
2. Offer one new allergen at a time. This makes it easier to identify the cause of a reaction.
3. Offer a small amount. A quarter to half a teaspoon is a reasonable starting point for many foods, but follow the guidance for the specific food.
4. Stay for the reaction. Watch your baby for at least two hours. Do not introduce a new allergen just before child care, bedtime or a long car trip.
5. Keep offering it if tolerated. Aim for around once or twice a week so tolerance is maintained.
6. Do not offer a new allergen when you are alone and far from help if your baby is at higher risk. Have a plan.

Signs of a reaction#

Reactions can be mild, moderate or severe. The same food can cause different reactions at different times.

Mild symptoms can sometimes progress. If you are unsure, call healthdirect on 1800 022 222 or your GP. If there is any breathing difficulty, throat swelling or collapse, call 000 immediately.

Getting a diagnosis#

If you suspect a food allergy, see your GP. They may refer you to a paediatric allergist or immunologist. Assessment usually includes:

• the history of the reaction and the timing
• a physical examination
• skin prick testing or a specific IgE blood test
• a supervised oral food challenge in some cases

These tests need to be interpreted by a doctor. A positive test does not always mean a clinical allergy, and a negative test does not always rule one out. Do not rely on unproven tests such as IgG food intolerance testing, kinesiology or hair analysis.

Never trial a suspected allergen at home if your child has had a significant reaction. A supervised challenge is the safe way to see whether an allergy has resolved.

Living with a food allergy#

If your child has a confirmed allergy, the day-to-day work is prevention and planning.

• Read every label, every time. Ingredients change.
• Learn the names of your allergen. For example, casein and whey are milk proteins; semolina is wheat.
• Ask about cross-contamination at restaurants, cafes and bakeries.
• Have an ASCIA action plan from your doctor, with a current photo and clear instructions.
• Carry the adrenaline autoinjector if prescribed, and check the expiry date.
• Teach childcare and school about the plan and where the medication is kept.
• Tell family and friends what to avoid and how to respond.
• Check medication and food labels when travelling.

For a baby, a wrap or carrier and a clean mat can help reduce exposure when eating out. Bring safe food and a spoon from home.

Prevention: what the evidence says#

The evidence does not support delaying allergenic foods. It also does not support avoiding them during pregnancy or breastfeeding. Current advice is to introduce them early and keep them in the diet.

There is no proven way to prevent all food allergies. Some research suggests early introduction of peanut and egg may reduce the risk of allergy in high-risk infants, which is why current guidance emphasises early introduction. If your baby has severe eczema, early specialist advice is important.

Do not use hydrolysed formula or other special formulas for allergy prevention unless a health professional has advised it for a specific reason.

Common mistakes#

• Delaying allergens until after 12 months. Current guidance recommends introducing them before 12 months.
• Introducing several new foods at once. If a reaction occurs, you will not know which food caused it.
• Giving up after a mild reaction without advice. A reaction needs assessment, not guesswork.
• Retrying a food that caused a severe reaction at home. This is dangerous. Get specialist advice.
• Relying on a blood test alone. Test results need clinical interpretation.
• Using unproven tests. IgG testing, kinesiology and hair analysis are not diagnostic.
• Forgetting the action plan at childcare. Staff need to know the plan and have access to medication.

When to get help#

See your GP or allergist if:

• your baby has a reaction to a food
• your baby has severe eczema, especially in the first few months
• you have a family history of food allergy, asthma, eczema or allergic rhinitis
• your baby is avoiding foods or not growing well
• you are unsure how to introduce allergens
• you need an ASCIA action plan or an adrenaline autoinjector reviewed

Call 000 for breathing difficulty, throat swelling, collapse or a severe reaction. For urgent advice, call healthdirect on 1800 022 222.

The bottom line#

Introduce common allergens around six months, one at a time, and keep offering them if tolerated. Know the signs of a mild reaction and anaphylaxis, have a plan, and get specialist advice for severe eczema or a known allergy. Most children with food allergy can live full, safe lives with good planning — and some will outgrow it.

For the practical side of starting solids, read our starting solids guide and baby-led weaning guide. If your baby also has eczema, our baby eczema guide explains the skin care that can reduce the risk of flares.