We use the descriptive term "food allergy" throughout this text despite the fact that the reaction patients experience is almost certainly not the classical allergic response at all.

There is a reaction, of that there is no doubt, but probably not one that classical allergists would label "allergy". We could substitute "hypersensitivity" or "intolerance" but it would then be simply down to semantics. As "allergy" means "altered reaction" and as food allergic patients experience just that on consuming ordinary foods, we will refer to the phenomenon as food allergy, whilst still being aware that we can include in that description not only foods, but drinks, and even chemicals within the foods and drinks.

Existing blood tests for food intolerance, or allergy, involve the taking of blood from the patient, exposing the blood cells to each individual food and searching for immunological involvement of specific antibodies such as IgA, IgE, IgG or IgM.

However, although the existence of any of these antibodies may be shown, it may have no clinical relevance - it may be of no diagnostic value - as the existence of such immunological activity does not prove that the particular food being tested plays any part in the patient’s symptoms.

These blood tests are assuming that the "allergy" involved in these particular food allergy reactions, is a classical or conventional allergy based on an immunologically-mediated mechanism, whereas it is becoming more and more clear that the food allergies or intolerances which produce common symptoms such as arthritis, fibrositis, migraine or depression may be quite different.

It appears they are not the "classical" allergies of old but a reaction based on non-immunological activity within the patient. Therefore blood tests for the food allergies being discussed here are often considered unreliable indicators.

There will of course be a number of people who will experience a reduction in symptoms by acting on the information given from these blood tests, but many people can get great relief from their symptoms merely by removing a number of foods from their diet anyway.

Even a list of foods to avoid that might not be fully accurate may still, by the law of averages, and by virtue of the fact it can only be a 50-50 chance, hit on a number of culprit foods thereby achieving apparent success by removing a toxic load from the system.

When the author of this kit sent off for an allergy blood test many years ago, he was advised that he could safely eat potatoes. But he knew from his own experience that potatoes were his No. 1 allergic food!

Recent "improved" blood tests for food allergies claim an extremely high "reproducibility" or "replicability" rate. Be aware that the choice of words is deliberate. Neither of these words means ACCURACY!

An indicator of the diagnostic mayhem and confusion which surrounds food allergy/intolerance testing methods came with a recent BBC Television investigation.

Their reporter went to three clinics for food allergy testing. Each clinic claimed to have the "best" and "most uptodate" equipment. The results below indicate just how effective these testing methods were. Remember too that it can only either be a positive or negative. It can only either be a yes or a no. It can only either be a black or a white. With a 50-50 chance of getting it right, even a GUESS couldn’t be far out!

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