There’s no doubt about it, the thought of your baby having an allergic reaction is really scary.

So, it’s no wonder that it’s one of the biggest worries parents have when they start their baby on solids. Nut allergies are one of the most common allergies in children, and can, in some cases, be very serious. But introducing nuts early in your baby’s life (between 6 and 12 months) can actually reduce their risk of developing an allergy.

So how can you introduce nuts to your baby safely?

Firstly, what causes an allergy?

Food allergies develop when our immune system mistakenly identifies a protein in a particular food as harmful. The immune system is then stimulated and releases substances such as histamines to fight off the perceived threat, and in doing so causes inflammation, which results in the symptoms of an allergic reaction.

How common are nut allergies

Australia has a relatively high rate of peanut and tree nut allergies, but thankfully this has decreased recently, most likely due to changes in food allergy guidelines.

At present, around 2.6% of infants aged 12 months have a peanut allergy, with tree nuts allergies being slightly less common (around 2%). Around 20% of these children will outgrow their peanut allergy.

Peanuts vs tree nuts

Despite both being classified as ‘nuts’, peanuts and tree nuts actually aren’t related and come from different botanical families. In fact, peanuts aren’t a nut at all, they’re a legume, like chickpeas or kidney beans - although most people with a peanut allergy can safely eat other legumes.

This means that most people are allergic to either peanuts OR tree nuts, however, 1 in 3 people with a nut allergy are allergic to both.

When should nuts be introduced?

Up until fairly recently, parents were told to delay the introduction of allergenic foods until after 12 months to reduce the risk of allergies developing. But, thanks to a lot of research over recent years, we now know that delaying the introduction of these foods doesn’t protect against allergies, and can actually increase the risk.

One particular study, called the LEAP study, was conducted in England from 2006-2014 and included babies at high risk of developing peanut allergy (babies with severe eczema, an allergy to egg, or both). It found that babies who were fed peanut under 1 year of age and included it regularly in their diet had an 86% reduction in peanut allergy compared to children who avoided peanut.

The percentage of children with peanut allergy in the group who avoided peanuts was found to be 17%, compared to 3% in the group who included peanuts regularly.

The idea for the LEAP study came from the observation that there is a low rate of peanut allergies in children in Israel, where peanuts are often included as part of a snack from as early as 4 months of age.

Thanks to this study and other research in this field, the advice now is to introduce allergenic foods at around 6 months, when babies are developmentally ready for solids (not before 4 months), and that all babies should have these foods by 12 months. This includes babies at high risk of allergy, unless an allergy to that particular food has already been confirmed.

Once allergens are introduced, continuing to give these foods regularly - around twice per week - helps to maintain tolerance.

How should nuts be introduced?

As with all allergens, it’s best to introduce nuts at breakfast or lunchtime so you can monitor for any reactions throughout the day.

Here are some easy ways to introduce peanuts and tree nuts. Start with a very small amount, around 1/4 teaspoon and gradually increase the quantity if your baby tolerates them.

Add some warm water to a teaspoon of nut butter (with no added sugar or salt) to make a warm puree, then offer your baby a small amount on a spoon (globs of nut butter can be a choking hazard)⁠
Add ground or finely grated nuts or nut butter to porridge, yoghurt⁠ or fruit or vegetable puree⁠
Add ground or finely grated nuts or nut butter to pancakes or muffins (for babies who are managing finger foods)⁠
Spread nut butter thinly on a finger of toast ⁠

NB: Never rub food on your baby’s skin as a way of testing for a food allergy. This will not help to identify a food allergy and can actually increase the risk of an allergy developing.

Introduce each type of nut separately

The term ‘tree nuts’ has limited meaning, as the types of nuts we classify as tree nuts actually come from a wide variety of different botanical families, although they do share similarities.

As each nut is slightly different and contains different proteins, children and adults can be allergic to one type of nut but able to tolerate another. For this reason, each type of nut needs to be introduced separately, ideally leaving 2-3 days between each one.

This includes:

Peanuts
Almonds
Walnuts
Cashew nuts
Pistachios
Pecans
Hazelnuts
Brazil nuts
Macadamia nuts
Pine nuts

Once you’ve introduced each type of nut separately, using mixed nut butter is an easy way to continue exposing your baby to a range of different nuts in one go, instead of having to include each one individually.

What if your baby is at high risk of a nut allergy?

If your baby has severe eczema or an existing food allergy, they are considered at high risk of other food allergies. If this is the case, speak to your doctor about how to introduce allergens.

Earlier introduction of allergens is sometimes recommended for high-risk babies as this has been shown to be protective

How to tell if your baby is allergic to nuts

An allergic reaction will involve one or more of the following symptoms.

Some allergies happen quickly and are easy to pick up, for example:

Swelling of the face
Hives
Runny nose
Vomiting

Others may be delayed and less obvious such as:

Eczema
Reflux
Poor growth
Diarrhoea or constipation

Usually, only a mild reaction occurs in children who are allergic to peanuts or other nuts. However, peanuts and tree nuts (especially cashews) are a common cause of anaphylaxis.

Anaphylaxis is the most severe form of allergic reaction which affects a person’s breathing and/or circulation and is life-threatening. The following symptoms indicate your child is having an anaphylactic reaction:

Difficulty with breathing and/or noisy breathing
Wheeze or persistent cough
Swelling of the tongue
Swelling and/or tightness in the throat
Difficulty talking or hoarse voice
Loss of consciousness or collapse
Becoming pale and floppy (infants/young children)

What to do if your baby has a reaction

The first time your baby has a mild or moderate reaction to nuts, take them to their GP. The doctor will confirm whether your child had an allergic reaction and advise you on what to do next time a reaction occurs. They may refer you to an allergy specialist if necessary.

In the case of a more severe reaction, the ASCIA 2019 guidelines state that ‘if you notice any swelling of the lips, eyes or face, hives or welts, vomiting or any change in your baby’s well-being (becoming very unsettled), soon after giving a new food, your baby could be having an allergic reaction. You should stop feeding your baby that food and seek medical advice.

Call an ambulance immediately if there are signs of a severe allergic reaction (anaphylaxis), such as difficult/noisy breathing or your baby becomes pale and floppy, or there is tongue swelling.’

The best treatment for a nut allergy, as with any food allergy, is to avoid them altogether. Sometimes, even trace amounts of peanuts and tree nuts can cause symptoms, so thorough food safety measures are needed to avoid cross-contamination and food labels need to be read carefully. If you’re unsure about how to avoid nuts and safely stick to a nut-free diet, a paediatric dietitian can help.

If your child is in childcare, you will need to work with them to develop a management plan specific to your child. This should also be communicated to any family members and friends who care for your child.

Reliable diagnosis of food allergy is important

It’s essential that allergies are correctly diagnosed and confirmed by a doctor. Your child’s doctor may order a skin prick tests or blood tests for allergen-specific IgE to help to confirm or exclude potential allergens. However, while these tests can help to determine whether a person is allergic or not, they don’t tell us how severe the reaction will be in those with an allergy.

Other forms of allergy testing are not evidence-based and therefore not recommended.

Avoid excluding nuts unnecessarily

Nuts are a very nutritious food, containing an impressive array of nutrients including protein, carbohydrates, healthy monounsaturated fats, iron, B vitamins and vitamin E. These nutrients are particularly important during infancy and early childhood when nutrient requirements are high.

For this reason, and to minimise the risk of an allergy developing, it’s not a good idea to unnecessarily exclude them from your baby’s diet just in case they have an allergy.

Nuts and choking

Nuts can be a choking hazard for babies and young children, so it’s important that they are served to babies in a safe way. Whole nuts, chunks of nuts and globs of nut butter should be avoided, instead, go for ground or grated nuts of thinly spread nut butter.