Food allergies in babies

The symptoms of a food allergy can be immediate, triggering obvious symptoms, such as a rash, as soon as the food is eaten. They can also be delayed, causing longer-term or recurring symptoms, such as eczema and digestive issues¹.

Food allergies are more common in babies than adults, affecting approximately 6–8% of children during early childhood². 

Reassuringly, many children outgrow their allergies as they move later into childhood.

As you begin your weaning journey and introduce your baby to solids for the first time, it’s important to look out for any reactions that might indicate a food allergy.

The most common, and immediate, signs and symptoms of a food allergy are:

• Swelling of the eyes, lips and throat
• Diarrhoea or vomiting
• Cough
• Wheezing
• Shortness of breath
• A runny nose, red eyes and sneezing
• Itching, hives and eczema

Allergy symptoms can be mild, moderate or severe. Some people experience the same level of symptoms each time they have an allergic reaction, but there’s no guarantee that they won’t be more severe if/when it happens again. 

That’s why it’s so important that if your child has a food allergy, it’s properly diagnosed, treated and managed.

Severe wheezing and difficulty breathing can be signs of anaphylaxis which is a severe reaction to an allergy and requires immediate medical assistance. Fortunately, this kind of serious allergic reaction is rare, and for more information you can visit anaphylaxis.org.uk.

Children born into families where allergies already exist are considered to be at a higher risk of developing allergies³. However, just because you have an allergy, it doesn’t necessarily mean your child will, too. Likewise, if there’s no history of allergies in your family, that’s not to say your child won’t develop one. 

It’s not uncommon for expectant mums to wonder whether the types of foods they eat during pregnancy can result in their baby developing an allergy. But in reality, if you’re pregnant or breastfeeding, you’re not required to avoid foods that can trigger allergic reactions, unless you're allergic to those foods yourself.

Experts advise that expectant mums eat a healthy, balanced diet and take care to look after their general health. 

Some food are more likely to can cause an allergic reaction than others⁴. For example:

• Wheat-based foods and other foods containing gluten
• Cow’s milk
• Eggs
• Fish and shellfish
• Peanuts
• Nuts
• Seeds
• Soya

It’s best to wait until your baby is around six months old before you introduce them to solid foods⁵. Once you’re ready to start weaning, it’s likely that you’ll be giving some thought to the types of food your baby can eat.

When it comes to introducing your baby to the foods that are more likely to trigger an allergic reaction, there are things you can do to reduce the risk of your baby developing a food allergy.   

Introduce the foods one at a time (one per day) and in very small quantities. If your baby tolerates them, they can then become a part of your baby’s usual diet. If your baby has a reaction, this gradual introduction of foods will help you to identify it³ and narrow down the cause.

Egg allergy is one of the common allergies, affecting 1 in 50 children in the UK, and it’s caused by the proteins in both egg white and egg yolk⁶.

NHS guidance states that you can introduce eggs into your baby’s diet from six months⁷. In fact, evidence suggests that the early introduction of eggs within the first 12 months of life can prevent your baby developing an allergy to them (the evidence also suggests the same for peanuts, allergies to which are discussed below)⁸.

Most children only have mild reactions to eggs, and symptoms of an allergy usually occur immediately after eating foods containing egg. Symptoms include a rash, swelling of the lips or around the eyes, and itching. Severe reactions are uncommon, but in the event that they occur they’ll need urgent medical attention so always be on the lookout for symptoms worsening^6.

To diagnose an egg allergy, your healthcare professional will usually perform an allergy test, for example, a skin prick test, or a blood test. These are commonly carried out if your baby has a history of typical reactions.

The best treatment is to avoid all foods containing egg. However, an egg allergy differs from other allergies in that whilst your baby may have a reaction to raw egg, they may be able to tolerate it once it has been cooked into cakes or biscuits, for example.

If baked/cooked egg is tolerated, then these foods should not be taken out of your baby’s diet. That’s because continuing your baby’s exposure to eggs will help them to grow out of their allergy quicker6. Many children will have outgrown their allergy by the time they reach school age⁹.

Always talk to your GP, health visitor or medical allergy specialist if you notice that your baby is showing symptoms of an allergy after eating eggs, whether that’s raw or cooked. They’ll be able to advise you on the foods your baby needs to avoid, how to interpret food labels and whether or not continuing to introduce cooked egg into your baby’s diet is advisable. 

Just like eggs, peanuts and other nuts should be introduced to your baby's diet the moment they start weaning at around six months of age. Waiting until your baby reaches 12 months or older to do so may in fact increase the risk of them developing a peanut or nut allergy¹¹.

For many children, a peanut allergy is lifelong, although research has shown that 1 in every 5 children will outgrow their peanut allergy at some point^9,10.  

When it comes to allergies, peanuts aren’t the only culprits. Tree nuts such as walnuts, hazelnuts, almonds, cashews and pistachios can act as allergens, causing an allergic reaction in some babies. It’s possible to be allergic to peanuts on their own, or a combination of tree nuts and peanuts.¹¹

Signs and symptoms of a peanut allergy usually occur within minutes of your baby having contact with foods containing them. However, it’s possible for them to appear up to one hour later.

It’s very important to seek advice from a healthcare professional if you suspect that your baby has a peanut or other nut allergy. That way, the allergy can be confirmed with a skin prick or blood test.

As there is no current treatment for an allergy to peanuts and/or other nuts, if an allergy is confirmed, it’s important to eliminate all foods containing them from your baby’s diet.

It’s vital that you always read the ingredients list on food items carefully, and remember not to reintroduce peanuts or any other food that might cause an allergy to your baby without medical advice¹¹.

If your baby has already been diagnosed with a food allergy, has eczema or you have a history of allergies in your family, it’s only natural that you might be concerned about your baby developing an allergy to peanuts. As such, you should talk to your GP, health visitor or medical allergy specialist first before introducing your baby to any food containing peanuts.

For many parents, the diagnosis of their baby’s food allergy can come as quite a relief. But it can also be the beginning of a lifelong journey - one which requires extra thought, care and planning on a daily basis.

Just because a baby or child has a food allergy, this doesn’t mean that they should be perceived as ‘different’ or excluded from any of the normal activities they might do with their friends. Whilst it might feel daunting to eat out, go to parties and functions and travel with your baby if they have a food allergy, there’s really no reason why you shouldn’t do all of these things.

Once you’ve got a good understanding of your child’s allergy, managing it on a daily basis can be relatively easy. Make sure that you provide anybody who cares for them with the information they need about their allergy, and details of the foods they can and can’t eat. And if your child is attending a party or event where food is provided, be sure to inform the host about any allergies your child has.

Always remember that spreading awareness around the issue of allergies is a good thing. Talking to other parents will not only help put your mind at ease, but also help others to understand what the impact of food allergies can be on children.

If you suspect that your baby has any kind of food allergy, call your doctor to discuss this further. They’ll be able to provide a diagnosis and offer support and advice on how to manage the condition.

Depending on the food your child is allergic to, avoiding it may mean that they’re at risk of missing out on key nutrients. It’s a good idea to seek support from a dietitian to ensure that your baby gets the full range of nourishment they need for healthy growth and development¹².