Here are some answers to key questions you may have on the subject.
What is a food allergy?
Food allergies occur when the body comes into contact with a substance it does not recognise (or no longer recognises as safe) and activates its defence system (your immune system) in order to eliminate the intruder. While there are many different symptoms, you should consult with a healthcare professional such as a dietitian or paediatric allergist for guidance on how to manage it.
How common are food allergies in children?
Food allergies occur in approximately 5-10% of infants in Australia, and can develop at any age.
What are the most common infant allergies to foods?
In early childhood, the most common foods which are likely to trigger an allergenic reaction are:
- Cow’s milk - Cow’s milk protein allergy is quite common, particularly in young infants, however most will grow out of it. Cow’s milk protein may be found in infant formula, small amounts in breast milk from the mother’s diet, and dairy foods. Advice from an allergist or allergy dietitian will be required if your baby is diagnosed with a cow’s milk allergy. It’s also important to note that an allergy to cow’s milk is different to lactose intolerance. You can read more on lactose intolerance here.
- Egg - It is recommended to introduce cooked egg to a baby’s diet before 12 months of age (scrambled or hard boiled are great options!). If your child is diagnosed with an egg allergy they will need to avoid egg, so get ready to become an expert in food labels! Many food products sold in Australia are manufactured using ingredients containing eggs, which means you need to read the label and list of ingredients carefully. A dietitian can help teach you the best way to read the food label. When starting your baby on solids, always introduce cooked egg (i.e., scrambled or hard boiled are great options!)
- Wheat - An allergy to the proteins in wheat, which may include ‘gluten’, is another common allergic food in Australia. As soon as a wheat allergy is diagnosed, all products derived from wheat must be eliminated from the diet. Lists of foods containing wheat can be found on reputable sites such as Allergy & Anaphylaxis Australia. Until a diagnosis is made it is recommended gluten be introduced from six months even if there is a family history of allergy. If introduced in conjunction with breastfeeding, your baby may be less likely to develop an allergy or intolerance to gluten.
- Soy - Soy comes from soybeans. While soy is one of the more common food allergens, it’s not as common as some of the others in this list such as cow’s milk and peanut. Like all food allergies, the primary management is to eliminate it from the diet. Soy can be an obvious ingredient, for example in Soy sauce, or a less obvious ingredient, for example as a vegetable protein source. On a positive note, most children grow out of their soy allergy by the time they reach school age.
- Peanuts - Peanut allergy is one of the more common allergies in this list of foods, and only about 20% of children grow out of it. Unless a diagnosis is made it is recommended to introduce peanut (paste) into your child’s diet before they are 1 year old. When your doctor diagnoses your child’s peanut allergy, they will also be able to guide your management plan. Like eggs and gluten, peanuts are present in many processed food products not necessarily designed for children. Learning how to read the label to determine if it contains (or may contain) peanuts, and then subsequently avoiding the product, will be key.
- Tree nuts - Tree nuts are a different plant type to peanuts, they include a variety of different nuts including almonds, walnuts, cashews, macadamia, pine nuts and pistachios, pecans, brazil nut and hazelnut. If your baby has been diagnosed with an allergy to one nut, there may be some cross over with other nuts and you will need to avoid those too. Nuts show up in foods in different formats, as whole nuts, pastes, flours and even oils, so read the ingredients list carefully.
- Sesame - Sesame allergy occurs when your body reacts unnecessarily to what should be a harmless protein. While most children with an allergy to sesame don’t grow out of it, the prevalence is quite low in comparison to the other foods listed in this article. Like all food allergies, avoidance of this food is essential once your baby has been diagnosed. When traveling or eating out, avoid sharing food and utensils with others. Having a backup snack ready in case you can’t find something will help.
- Fish - A fish allergy is more commonly life-long and occurs in adulthood as opposed to childhood. If your baby is allergic to fish, there is sometimes a cross-over with crustaceans, but not always. Interestingly, there is also some cross-over with crocodile as they have similar proteins to fish. Your doctor will guide you regarding which fish to stay clear of.
- Shellfish - Shellfish are split into two groups – molluscs (e.g. oysters, squid and scallops), and crustaceans (e.g. crab, lobster and prawns). If your baby reacts to one crustacean, they are more likely to react to another. With fish and shellfish, there is often cross-contamination due to where it’s sold and stored.
What are the symptoms of an allergic reaction?
Depending on the food responsible, symptoms to look out for can include vomiting, stomach pains, hives, eczema (a baby allergy rash), asthma and recurrent ear, nose, and throat infections. If your baby experiences any of these signs of allergy to a food, you should speak with a healthcare professional as soon as possible.
Sometimes, a food allergy can cause a severe reaction, otherwise known as anaphylaxis. Severe symptoms could include swelling of the lips, tongue or throat, persistent dizziness and wheezing or difficulty breathing. If your child is showing signs of anaphylaxis, call emergency services immediately.
Does breastfeeding help to protect against food allergies?
The evidence for protecting against allergies by breastfeeding is inconsistent however breastfeeding remains extremely important. Breastfeeding is recommended exclusively until around 6 months of age and should be continued whilst solid foods are introduced, and beyond. When looking at the immune system, breastfeeding supports the development of a healthy gut microbiota, where approximately 80% of our immune cells live.
Who can diagnose an allergy?
In the first instance, your GP or paediatrician may send you for a children’s allergy test such as a blood test or skin prick test. It is then recommended that you consult an allergist. You can even find specialised infant allergists. There is no limit on what age to test baby for allergies.
There is a history of allergies in my family. Is this a factor?
A parent or sibling may have allergies without the new baby inheriting the same allergy. That said, a higher level of food allergies has been observed in children with a family history of allergy and intolerances. If you have a family history of allergies you should let your healthcare professional know as this may help them advise you on ways to reduce the risk of allergies occurring in your baby.
Can food allergies in children be cured?
No medical cure currently exists for food allergies. However, it is possible that your baby will outgrow their allergy. Your doctor may conduct food challenges down the track, where small amounts of the allergic food are given to them under strict medical supervision, to test tolerance and whether they have grown out of it.
What is the difference between a food allergy and intolerance?
It is very common to be confused between a food allergy and food intolerance as many symptoms can be similar. Food intolerance doesn’t involve the immune system and is often a lot more difficult to diagnose. Food allergy on the other hand involves an immune response and can be confirmed through allergy testing. Food allergy can also result in more serious reactions than an intolerance, such as anaphylaxis. If your child has any reaction to food, it’s important to talk to your doctor.
Should I introduce common food allergens into my baby’s diet?
Australian guidelines recommend introducing solid foods at around six months of age. The introduction of common allergenic foods should not be delayed, unless advised otherwise by your healthcare professional.
Signs of allergies in babies can occur straight after a food is eaten, or several hours later. Try to introduce allergenic foods one at a time and in small amounts so you can spot a reaction more easily. Once introduced and shown to be tolerated, try and include allergenic foods in your child’s diet often and regularly, as this can minimize the risk of a future allergy.