Food Intolerances Exposed
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- July 31, 2018
Our Resident Nutrition Consultant, Kate Arnold gets to grips with food allergies and exposes the issues surrounding food intolerances and how they are tested.
So firstly, what exactly is a food allergy? Food allergies occur when a food triggers a reaction in the immune system. The body mistakenly makes an antibody (IgE) to fight off the perceived allergen. Food allergies are uncommon but can affect both children and adults. Examples of the most common food allergies include eggs, milk, fish and nuts.
What are the symptoms of a food allergy? Symptoms of food allergies are wide ranging, but can include histamine responses such as itching, a rash or vomiting and diarrhoea. In rare cases the allergy may trigger an anaphylactic response which would need emergency treatment. An EpiPen can be carried by those who have severe reactions. Symptoms of food allergies are quick to appear, generally within minutes of exposure.
What is a food intolerance and how is it different to a food allergy? While food intolerances may affect a higher proportion of the population than food allergies, both are not common. It is difficult to be scientifically accurate when assessing food intolerances and, as such, this lack of evidence leaves intolerances exposed to pseudoscience. As a result many people wrongly believe they are intolerant to a particular food. Food intolerances, although more common than food allergies, are still also uncommon and symptoms such as headaches and Irritable Bowel Syndrome (IBS) type pains are much slower to appear. Common foods that may cause food intolerance are wheat, gluten and dairy. However, it’s important to be aware of the difference between these two, because unlike food intolerances, there are valid food allergy tests, one which includes an IgE blood test. Food allergies can also be life threatening so definitely see your GP if you suspect this.
So is there any science behind food intolerances? So called food intolerance testing looks for specific IgG antibodies to foodstuff in the blood, claiming that a positive result indicates diagnosis of a food intolerance. They typically involve long lists of foods which seem to always include wheat, dairy and other sources of FODMAPs. (These are short chain carbohydrates, poorly absorbed in the small intestine). This long list and inclusion of FODMAPs may explain why some people report feeling better after implementing the IgG test results i.e. it’s a chance finding! Most of us will develop IgG antibodies to food during our lifetime. It is an indicator of repeated exposure, not clinical symptoms. This is because IgG is a marker for food tolerance: an indicator that our immune system recognises the food to be harmless and does not respond. IgG antibodies to a food may therefore be protective in preventing inappropriate immune responses by diverting the immune system away from IgE (i.e. the allergy type of response).
Do you have any personal experience of food intolerances? Actually yes I do, so I can definitely speak from personal experience. Over the years I’ve done repeated IgG food intolerance testing on myself to prove this is pseudoscience. The first test was about fifteen years ago and I was given a list of about twelve foods that I was told to avoid. The problem with the results was that I had no problem with these foods. The list included salmon, ginger and garlic, foods I ate much of the time. I was lucky enough to get the test free but the the test was expensive to the general public and fundamentally for me, it was worthless. Hundreds of people walk through my doors claiming they have been told by muscle testing or machine that they have food intolerances and it’s all just a lot of hokum. What the practitioner or therapist has, is a small amount of knowledge with little understanding of how the body functions and clearly lacks the qualifications to understand IgE allergy or how the immune system works. Just because you bloat on a food does not mean you are intolerant. There are many reasons why you bloat, e.g. after a plate of pasta, and it’s not necessarily because you are gluten intolerant. It might simply be you are ingesting a plate of high FODmap foods or the amount of carbohydrate has found it’s way to certain bacterias in the large intestine like Klebsiella that thrive on carbohydrate. If people knew and understood this you would get a totally different set of results.
How can you test for food intolerances? There are a few ways of testing for so called “food intolerances”, none of them scientific, even though the practitioner can be well meaning and trying to help.
1. The IgG Elisa Allergy Test: This test measures IgG and IgG4 antibodies to various foods which should not be confused with IgE antibody testing. Most people develop IgG antibodies to foods they eat and this is a normal non-specific response indicating exposure but not sensitisation. There is no convincing evidence to suggest that this test has any allergy diagnostic value. In fact, the IgG response may even be protective and prevent the development of IgE food allergy! For example, IgG4 antibodies produced after high level cat allergen exposure in childhood confer cat allergy protection and not sensitisation.
2. Vega Testing and Bioresonance machines. This test was developed by German physician Dr Reinhold Voll in 1958. The Vega Test involves measuring electromagnetic conductivity in the body using a Wheatstone bridge Galvanometer. The patient has one electrode placed over an acupuncture point and the other electrode is held while a battery of allergens and chemicals are placed in a metallic honeycomb. Katelaris et al and Holgate performed independent double blind testing, comparing Vega testing with conventional testing in known allergy sufferers, and the Vega Tests had no reproducibility or diagnostic accuracy at all. The manufacturer’s aggressively promote the test and offer free training courses for potential “allergy” diagnosticians. I have tried both these tests and was horrified at the findings which were so inaccurate.
3. Hair Analysis Testing: Hair is analysed for allergies in two ways. First of all, the hair is tested for toxic levels of heavy metals such as lead, mercury and cadmium and then deficiencies of selenium, zinc, chromium, manganese and magnesium. There is no scientific evidence to support the hypothesis that these heavy metals have any bearing on allergic diseases. Hair samples are usually sent away for analysis and numerous studies have failed to find any accuracy in hair analysis diagnosing allergies.
4. Applied Kinesiology (Muscle Testing): This was developed in the USA by Goodhart in 1964 and relies on energy fields within the body to diagnose allergy and intolerance. In this test, the practitioner tests the patients muscle strength when the allergen is placed in a vial in front of them. The shoulder strength (Deltoid muscle) is usually tested for weakness. The patient holds out their arm and the practitioner applies a counter pressure – if the patient is unable to resist the counter pressure, the test is considered positive to that allergen. The antidote to the allergy is then also held in front of the patient and if their weakness is reversed – this indicates it is the correct antidote. There are a number of variations to the technique of muscle testing and many practitioners complement the test by holding a magnet in front of the patient. There is no convincing evidence that this test has any useful role to play in allergy diagnosis. I have also tried this testing, again the diagnosis was widely inaccurate and alarming.
Can you test vitamins and minerals by using hair, muscle testing or machine?No. You can only test vitamins and minerals but taking a venous sample of blood and sometimes urine depending on what you are testing.
Am I wasting my time and money with these tests? Obviously life is about choices but the short answer is yes. When you are sick, you are vulnerable and easily susceptible to quick fixes and diagnoses that seem to make sense. These machines are not scientific in any way. I also see the devastating consequences of unqualified practitioners giving the wrong advice. If you stand back for a moment and think about what you are being told; gluten free, dairy free, yeast free, sugar free. If you are eating junk food and cut out these foods, sure you will feel better and lose weight for a short while, but this is not a long term strategy. Eliminating huge groups of food is not a good idea. These practitioners rarely have access to blood testing, will not liaise with consultants or GPs and can hide behind the machines because that is the only way they can “diagnose”. On a more serious note, I’ve seen clients who were diagnosed as having the BRCA gene, parasites, candida, B vitamin deficiencies, magnesium deficiencies and so on, some serious, some not so and when they were eventually tested properly, none of these so called diagnoses were found. The psychological ramifications are also very serious. Many people are so blind sided by these results that they are scared to eat and can easily became orthorexic. Convincing them that the machines might be wrong can be a huge undertaking.
Can lactose intolerance be classed as a “food intolerance”? Lactose intolerance is an absence of the enzyme lactase which breaks down milk sugar and should be treated as a separate condition. It has nothing to do with IgG or food intolerances.
How should you deal with food allergies and intolerances? If you have a bad allergic reaction to a food, go and ask your GP for advice. IgE allergy tests are useful in assessing the trigger or, if your symptoms are severe enough, an EpiPen can be prescribed. The NHS are not great at allergy testing due to funding and other issues but IgE allergy tests are available with your local GP. Occasionally you might be referred to an allergy specialist. It is also important to keep a food diary to monitor any food allergies or food intolerances you think you may have.
Ok, so in conclusion what are your take home messages? In conclusion I would say: Allergies are rare, food intolerances are even rarer. Look at your gut first and see how best to feed your gut microbiome, or get that tested. IgG tests lack both scientific rationale and clinical evidence for diagnosing a food intolerance. IgG tests should not be confused with valid IgE allergy testing. There is no other way to test for lactose intolerance other than breath tests. If you want to know, do the test or avoid lactose for six weeks and see if the symptoms improve .If you think you have a food intolerance, you need expert help, and it may only mean removing one or two foods from the diet for a period of time, if it’s starting to look like a long list of avoidance, something is not right. I will leave you with Dr Adam Fox, a consultant children’s allergist at Guy’s and St Thomas’ NHS Foundation Trust, who says “tests involving hair sampling or electromagnetic waves have no scientific validity“. There is a danger of over-diagnosing allergies that are not there and failing to diagnose genuine allergies”.
If you want any advice or help regarding this article please contact Kate on 01323 /310532/737814 or go to www.katearnoldnutrition.co.uk for further information.
