What's The Differnce Between An Allergy And An Intollerance?

[Marijn]

What's the difference between an allergy and an intollerance/hypersensitivity? I read something about Icg and Ice (I think those were the terms used), but can someone give me a layman's explanation, please.

[Marijn]

Thanks Lazygun. Is it really completely useless? Dr Chris Steele and Dr Hilary Jones endorse it. I don't understand why they would put their reputations on the line?

[LazyGun]

@Notafish. In my opinion, as a diagnostic tool for determining a food allergy, the IgG test has no value.

Even an IgE test is not absolutely specific. Let me give you an example. If we were to perform the IgE test for peanut allergy on a random 100 people from the street, we would expect a positive result in 8 out of every 100. But not all 8 will actually have an allergy to peanuts. In fact, it is estimated that peanut allergy affects only around 1% of the population, or 1 in every 100 of people randomly selected.

So perhaps you can begin to appreciate the problem, There is currently no single simple diagnostic blood test that can offer a clinically significant result.

Food allergies are best tested with the rather labourious and time consuming "food challenge" tests, backed up with various diagnostic blood tests if and when an allergy or an intolerance is detected, and a family history and personal medical history are probably the most important bits of information.

A quite sensible link for you notafish:
http://www.npr.org/blogs/thesalt/2012/03/19/148950092/to-find-out-about-food-allergies-first-use-the-right-test

From the article,
"An article in the current Canadian Medical Association Journal reminds doctors that IgG tests aren't reliable tests of food allergies.

It follows the guidelines on diagnosing food allergies from the National Institute of Allergy and Infectious Disease in 2010, which lumped IgG testing with more than a dozen "nonstandardized and unproven procedures" that should be avoided. A positive IgG test, the expert panel said, could cause people to avoid foods that they can safely eat"

There remains a gulf of misunderstanding between the general public and medical professionals about how and why food allergies and intolerances affect us. Even amongst medical professionals there is some confusion.

This gulf of misunderstanding in the perception of what is a food allergy or intolerance is best illustrated by the % of people who are convinced they suffer from such a disorder, and the actual % of the population who can demonstrate clinically that they do in fact have such a problem.

The immune system is often thought of by members of the public as a kind of personal defence system which works in a manner analogous to a sort of simple muscle response. It is far far more complicated than that, and it is actually a very unhelpful misperception.......

[Marijn]

Thanks for all your input Lazygun. The York Test Laboratory are NOT testing for allergies though and not claiming to. The are looking for intolerance or hypersensitivity. In the article in your link, it says that the best way is for the doctor to give the food substance to the patient in his office, then see if he/she gets ill. Well, that's not going to work if the symptom of the hypersensitivity is fatigue or bloating as these are not immediate and they accumulate over time. I'm not entirely convinced the York Test is useless, but I doubt it's as good as THEY say it is. I just don't know what to take from the results now. :-(

[LazyGun]

@ Notafish - But they do suggest - in fact their whole testing program is based upon - the notion that an IgG test is diagnostic for either food intolerance or food allergy, and I think that most eminent medical professionals who specialise in this area would dispute this.

They offer a basic IgG test, then a follow up panel test, but I would question the value of such tests, and I would question the value for money of the panel tests they offer. Telephone consultations in matters of food intolerances and diets are not especially helpful either.

I empathise with your situation, but there is really only one way to identify and isolate a particular food or food group that might be causing an adverse problem, and that is by keeping a food exclusion diary.

From allergy UK
"The Gold Standard, and only reliable way, to find out which foods are causing adverse reactions in an individual, is by keeping a very clear food and symptoms diary alongside a food exclusion diet. The diet needs to be followed strictly for purposes of diagnosis. This exclusion is then followed by a period of structured reintroduction of foods one by one, whilst keeping an accurate food and symptom diary all along. This is the most reliable way of ‘testing’ for any adverse reaction to a food. This is best done under the supervision of a registered dietitian. GPs can refer suitable candidates to a dietitian. This method of diagnosis is ideally most suitable for people who are prepared to follow the advice strictly and be prepared to keep a food and symptom diary."

I would definitely recommend discussing this with your GP. It is my understanding that you can get a reference to a nutritionist who can guide you and supervise this process.

http://www.allergyuk.org/food-intolerance/identifying-your-food-intolerances

I don't know where you are based, notafish, but you might wish to consider contacting allergy UK yourself - they may very well be able to point you in the direction of some local help and/or support.....

[Marijn]

I can't find the letter, booklet and food diary they sent me with their results. When I find it I can quote exactly what they say. If you have the patience to comment on it again afterwards, no worries if not. I appreciate your input, it's been interesting talking to you. A friend at work recommended the York Test Lab to me, so we have both done it. I don't know whether to tell her all your findings, as it will probably p*ss her off that she's spent all that money. Also I do appreciate there is a correct and slow, laborious way of checking for your own intolerances, but sadly I'm basically a very lazy person. :-(