Food allergies Mate pāwera kai

Most food allergies start in childhood.

Allergies likely to be outgrown by age 5 include:

• cow's milk
• eggs
• soy
• wheat.

Allergies that are more likely to be lifelong include:

• peanuts
• seeds
• seafood
• tree nuts.

Adult-onset food allergies are not common. Food intolerance is much more common in adults and can be due to a variety of causes.

Common allergy-causing foods include:

• eggs
• fish and shellfish
• cow's milk
• peanuts
• sesame seeds
• soy or soybean products
• tree nuts such as almonds or cashews
• wheat.

In Aotearoa New Zealand, these ingredients must be put on food labels, even if the product only contains very small amounts.

Not all bad reactions to foods are due to an allergy. They can be due to:

• food intolerance
• toxic reactions
• food poisoning
• enzyme deficiencies
• food aversion.

Symptoms of adverse reactions to foods can include:

• headaches after having chocolate or red wine
• bloating after drinking a milkshake or eating pasta.

Symptoms of an allergic reaction to food normally develop immediately after, or within hours of, eating.

In most cases, the allergic reaction may cause mild to moderate symptoms.

Mild to moderate symptoms include:

• itching and hives (urticaria)
• swelling around your lips, face and eyes
• tummy pain
• runny poos (diarrhoea)
• feeling sick or throwing up
• sneezing.

In rare cases, it can cause a severe reaction called anaphylaxis.

Severe allergic reaction (anaphylaxis) signs include:

• swelling of your tongue
• tightness in your throat
• wheezing or difficulty breathing
• difficulty talking or hoarse voice
• dizziness or collapse
• being pale and floppy (in young tamariki).

Although allergic reactions to foods are common in Aotearoa New Zealand, death from anaphylaxis due to food allergy is very uncommon.

The most common foods causing life-threatening anaphylaxis are:

• peanuts
• tree nuts
• shellfish
• cow's milk
• eggs.

Most deaths can be prevented by:

• avoiding foods you are allergic to
• using an adrenaline autoinjector, such as an EpiPen, immediately if you do have a severe allergic reaction to foods.

If you are concerned you may have a food allergy, see your healthcare provider for a diagnosis.

It is important to get a reliable diagnosis of a food allergy before restricting a particular food in your diet, as this can cause malnutrition.

Your healthcare provider will ask you about allergic symptoms, such as a rash or an upset stomach, and their relationship to food.

It is easy to identify which food is causing the reaction when symptoms appear rapidly after eating it. But if the cause is unknown, other diagnostic tests may be needed.

Your healthcare provider may refer you to a test for the presence of an antibody that causes an allergic reaction. This will either be a:

• skin prick test
• blood test.

They may also refer you to an allergy specialist for further tests if the cause is still unclear.

Despite your best efforts to avoid particular foods, you may be exposed to them accidentally.

• Learn to recognise the signs of an allergic reaction and anaphylaxis and know what to do in an emergency.
• Have an allergy action plan that outlines what to do if you have an allergic reaction.
• Always carry your allergy action plan, or put your action plan somewhere easily accessible in your home. If you do not have an action plan, ask your healthcare provider to fill one out with you.
• Always carry your adrenaline autoinjector with you if you have been prescribed one.
• Wear a medical alert bracelet or necklace so medical staff know how to treat you in a medical emergency.
• Have a plan when travelling.

Action plans — Allergy New Zealandexternal link

At school and preschool — Allergy New Zealandexternal link

If you have a mild or moderate allergic reaction, the treatment aims to relieve your symptoms. Antihistamines are the most commonly used medicines. These relieve itching or hives on your skin.

Adrenaline is used to treat severe allergic reactions (anaphylaxis). It can be administered through an autoinjector to slow down or stop a severe allergic reaction.

If you have a food allergy and are thought to be at higher risk of developing anaphylaxis, your healthcare provider can teach you how to inject adrenaline using an EpiPen.

You will also need to have an anaphylaxis action plan that documents what to do if you have anaphylaxis and when to call for help.

Action plans — Allergy New Zealandexternal link

There is currently no known cure for food allergy. The use of desensitisation, known as oral immunotherapy, is being researched.

You can only prevent the symptoms of a food allergy by avoiding the food you are allergic to. After you have identified the foods you are sensitive to, you must stop eating them.

Some of the ways to minimise your risk of being exposed to a particular food allergen include:

• telling others, such as restaurant staff, of your food allergy when eating away from home
• telling schools of your tamariki's food allergy
• not sharing or swapping food or utensils with others
• asking about food ingredients when offered food by others
• being aware of cross-contamination of food allergens when preparing food
• washing hands and surfaces to prevent cross-contamination
• knowing how to identify your food allergen and checking food product labels
• having a travel plan for any trips away from home.

At school and preschool — Allergy New Zealandexternal link

Vaccines

Know which vaccines to avoid if you are allergic to eggs. These include:

• yellow fever vaccine
• Q fever vaccine
• the Rabipur brand of rabies vaccine.

Your healthcare provider can provide advice and more details about these vaccines.

Reading and checking food labels

The Australia New Zealand Food Standards Code requires food labels to declare certain foods and substances in foods.

If you are allergic to a certain food, try to learn the different names used to describe that food on food labels.

For information, read the Ministry for Primary Industries' booklet 'Eating safely when you have food allergies'.

Food allergies and intolerances — Ministry for Primary Industriesexternal link