Allergy Or Intolerance?

allergy.jpgWe're so obsessed with food these days that it's not surprising that many people believe they are intolerant or even allergic to something. In reality, only about 2% of adults have a real food allergy - and it is 3-4 times more common in children.

So what's all the hype about? Here's a simplified guide...



WHAT'S THE DIFFERENCE BETWEEN FOOD ALLERGY AND INTOLERANCE?

Both allergy and intolerance are adverse food reactions.

In the case of a classic allergy, the immune system reacts to a foodstuff by making IgE antibodies and shows a characteristic set of symptoms including:

  • rashes
  • eye/face/lip/tongue swelling
  • vomiting
  • diarrhoea
  • bloody poo (children)
  • breathing difficulties/wheeze
  • anaphylactic shock (rarely)


These symptoms usually come on within a few hours and can become serious.

Intolerances are reactions that don't involve the immune system in this way.  They are much more varied in terms of causes and symptoms.  For example, it could be because of an enzyme deficiency (e.g. lactose intolerance) or because of a chemical side effect (e.g. palpitations from caffeine).  Symptoms include:

  • rashes
  • nasal congestion
  • nausea
  • stomach pains/bloating
  • flatulence/diarrhoea


These take much longer to come on (days) and are seldom serious.

 

HOW DO I FIND OUT IF I HAVE AN ALLERGY?

Diagnosing an allergy or intolerance involves a careful medical assessment by a doctor looking at history, signs and symptoms - and it isn't easy.  It can be difficult to tell between the two because the symptoms can be so similar.  However, the difference is that tests can be done to look for a true allergy, but usually not for an intolerance.  These tests include skin-prick testing, blood tests and a proper food challenge.

There are various testing kits in the shops claiming to diagnose intolerance.  These have not been clinically proven and the evidence behind them isn't clear-cut.  You may end up causing yourself more concern than necessary!

 

WHAT SORTS OF THINGS ARE CHILDREN ALLERGIC TO?

The most common allergens in children are:

  • eggs
  • milk
  • soya
  • wheat
  • peanuts

 

Fortunately, many children will grow out of their allergies with time.

 

HOW IS IT TREATED?

Treatment is simple: avoid the food you are allergic to.  If you are diagnosed with an allergy you should be provided with information on how to avoid the offending foodstuff and an emergency care plan (which may include a special EpiPen or AnaPen).

It is very tempting to do, but excluding something from your diet should only be done with the agreement of your doctor as it can lead to deficiencies.  Often a dietician also needs to be involved.

One of the commonest concerns in kids is cow's milk allergy.  It's not uncommon to see babies that get really upset after feeding and have really loose poo with blood in it.  Treatment might involve excluding cow's milk from your diet if you are breasteeding, or changing to a specialised milk formula.  The current advice is to avoid soya milk in babies if you can and goat's milk is definitely not suitable.

There's been a lot of debate about how to diagnose food allergy in children (and fortunately NICE has now issued some guidelines - see here).

 

If you need more information on allergy go to www.allergyuk.org