Help and hazards in testing

According to Dr Sarah Schneker of the British Nutrition Foundation, thousands of people are being ripped off by clinics charging for allergy tests that are useless. She warns that those that give long lists of foods to avoid can result in people cutting out major food groups, and should be considered a health hazard.

The debate over whether food allergies really exist remains controversial, with some doctors arguing that they only affect around one per cent of the population. Many nutritionists however, say they may afflict more than a third of all people.

Much of the disagreement is over definitions, with doctors referring to "classical" allergies such as peanut allergies or asthma attacks which provoke an immediate, sometimes lifethreatening response. Anaphylactic shock, a severe systematic reaction, can kill because of a drastic fall in blood pressure, swelling in the throat or by triggering a fatal asthma attack.

However, if you are suffering from symptoms such as tiredness, headaches, irritable bowel syndrome and eczema, you could have a food intolerance or sensitivity. These are often labelled "allergies" by nutritionists and complementary practitioners - which exasperates many traditionalists.

The theories behind why some people react to food vary, and some argue that the immune system is so complex that the tests - even the IgG test - are questionable. Many say that an elimination diet, under medical supervision, is the only precise way of pinpointing food intolerances. Foods most commonly connected to allergies, including wheat and dairy products, are cut out from the diet for 20 days.

If you are concerned about a suspected food intolerance or allergy, ask your GP for advice. If your GP cannot help, ask for a referral to a specialist who can.

For further details, check out www.allergy.co.uk