Food allergies and intolerances

Recognising the symptoms of a food allergy or intolerance

Although there has been an increase in the number of food allergies and intolerances diagnosed in children, in most cases the reaction to the food is fairly mild. Find out which foods are the most common culprits and how to recognise the symptoms.

Allergies

An allergic response to a food involves the immune system and symptoms are usually fairly immediate. This happens when the immune system mistakes harmless proteins in a food for dangerous substances. An immune response is set off and the body releases histamine, which is what causes the classic symptoms of an allergic reaction, such as hives and itching. This almost instant response means that real food allergies are pretty easy to spot – when your child’s eyes turn red and watery straight after eating scrambled egg, this is likely to be the culprit! The severity of allergic reaction varies, but most are fairly mild.

However, some of the more serious reactions, known as anaphylaxis, can affect breathing and must be treated as an emergency.

Recognising the symptoms

If your child has an allergic reaction to a food, symptoms are usually instant and can affect different parts of the body:

• A red, itchy rash around the mouth or eyes, that may spread over the body
• Raised itchy hives on the skin
• Swelling in the face, in particular the lips and eyes
• Watery eyes, and a runny or blocked nose, and sneezing
• An itchy mouth and throat

Symptoms of a serious anaphylactic reaction include:

• Wheezing and a feeling of tightness in the chest
• Swelling of the tongue and throat, which can restrict the airways
• A drop in blood pressure
• Dizziness, confusion and sometimes loss of consciousness

Food intolerance

This is an adverse reaction to a particular food that doesn’t involve the immune system. These are more common than allergies, but because symptoms appear more slowly – the reaction can occur hours after the food has been eaten – they can be harder to spot. If you suspect a food intolerance, try keeping a food diary of what your child eats to see if a pattern emerges. Food intolerance, while unpleasant, is never life-threatening.

If your child has an intolerance to food, symptoms are usually confined to the digestive tract and include:

• Bloating and tummy pain
• Wind
• Diarrhoea and /or vomiting
• Constipation
• Reflux

Foods most likley to cause a reaction

A common childhood intolerance is to milk and other dairy products, known as lactose intolerance. Other foods that may cause a reaction include eggs, fish, shellfish, wheat, kiwi, sesame seeds and nuts.

What should you do

Allergies:

If you suspect your child has a food allergy, the first thing to do is to avoid giving him the food again.  Consult your doctor as soon as possible, as simply withdrawing the food without getting a proper diagnosis could mean he misses out on important nutrients. Your doctor can arrange a referral to a specialist allergy clinic where a diagnosis can be confirmed.

Food intolerance:

If you think your child may have a food intolerance, keeping a food diary can reveal a pattern of symptoms that can help you to identify the culprit and is useful to show your doctor. Seeing a paediatric dietician is also worthwhile if a food intolerance is diagnosed: lactose intolerant children, for example, will need replacements for dairy products such as soya or rice based milk and they may need calcium and vitamin D supplements.

Living with a food allergy or intolerance

Once an allergy is confirmed, of course your child needs to avoid eating the food in question, but this may leave you feeling concerned about which nutrients he is missing out on. It’s worth consulting a paediatric dietician who can tell you not only what to avoid (foods can be hidden under other names in packaged products), but also how to compensate for nutritional shortfalls in his diet.

What's the outlook?

The good news is that while some allergies are usually life-long, such as a peanut allergy, others, such as dairy and egg allergies, are often outgrown during childhood. This is why the specialist will consider retesting your child as he gets older to check if an allergy has receded. If this is the case, he can be gradually weaned back onto the food.