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Lifelab Testing™ are backed by the help of expert Nutritionist Sian Baker. Our research and knowledge comes from years of tried and tested knowledge.

Sian Baker, DipION mBANT mCNHC

Allergy or Intolerance?

An allergy is the body’s immune system responding to what would normally be considered a harmless substance such as pollen, food, mould, pets’ hair, insects, medicines or house dust mites. The body perceives this substance to be a ‘threat’ and produces an inappropriate response, with symptoms usually starting within a few minutes but also as long as two hours later. Whereas a food intolerance is a difficulty digesting certain foods and experiencing physical symptoms as a result of eating them, with symptoms emerging hours to days later.

Allergy = fast symptoms
Intolerance = symptoms emerging later

What is an allergy?

An allergy is a type I hypersensitivity meaning that exposure to an allergen results in the production of immunoglobulin E (IgE) antibodies, the release of histamine and symptoms. It is an immediate response known as an IgE-mediated immune response with symptoms occurring almost straight away, as soon as the offending item is ingested, inhaled or touched. Symptoms do not always happen immediately and can occur up to a couple of hours later.

Allergens are usually easy to identify due to the quick nature of the reaction within the body, however this does depend on the severity of reaction as well as other factors such as hydration, time of year and sometimes even the processing level of a food.

Many people know an allergic response to a food or non-food item has the potential to be life threatening in certain individuals. In the case of severe allergy even the tiniest traces of an allergen will have an effect on the body and will trigger an immune system response. This is because the immune system attacks a particular protein as though it could be a harmful pathogen.

Depending upon the type of item ingested and the individual, the symptoms will present themselves differently. They can appear in the form of skin rashes, hives, vomiting immediately after ingesting food, wheezing, coughing, nausea and even the swelling of mouth, throat and tongue. An individual with multiple allergies may also have different symptoms to different items.

When seeing these symptoms, it is so important that you know what to do, as an allergic reaction has the potential to be very serious. If diagnosed with food allergies, you must do your best to consistently avoid these items and in particular if you have severe allergies or asthma, so to avoid a potentially life-threatening situation. It is important to note that type I allergies are a lot less common than intolerances and sensitivities.

What is the difference between IgE & IgG4?

Our body’s defence system, the immune system, protects us from disease. Antibodies produced by the immune system are one method of protecting us from foreign bodies. They recognise and prevent bacteria and viruses from entering the body. The IgE class of these antibodies is responsible for allergic reactions. Lifelab IgE tests will provide you with results on certain allergies.

If you believe you have an allergy you will need an IgE test. If you believe you have an intolerance you will need an IgG4 test.

The IgG4 subclass is the least abundant type of antibody, and often needs building up. Intolerance reactions are usually subtler than IgE symptoms – and include headaches, nausea, stomach cramps, diarrhoea or constipation, fatigue, skin disorders and lethargy – but can cause long-term damage and chronic discomfort. Lifelab IgG4 tests will provide you with results for an intolerance.

Why Do We Test IgG4 Over Total IgG Or IgG1?

Food allergies, intolerances and sensitivities are becoming more topical in a variety of sectors in the healthcare industry. It is a constant talking point for both health professionals and their patients. Nutrition as a topic and, more specifically allergies, intolerances and sensitivities, are getting more coverage than ever in the media. This is helping spread awareness about potential symptoms and the benefits of testing.

IgG1 and IgG4

In order to test for immune-mediated intolerances specifically, testing for IgG antibodies is required. Within the IgG class there are four IgG subclasses. There are a range of IgG tests, which are available to health professionals all over the world, some testing all subclasses and others testing one subclass but there are on-going discussions about which is the most effective. Of the four subclasses the most commonly tested are IgG1 and IgG4, as these are produced in response to food antigens and therefore can be used to identify intolerances. IgG2 and IgG3 are not generally produced in response to food antigens. The main difference between IgG1 and IgG4 is how they respond to food antigens. IgG1 antibodies are like ‘first responders’ and are produced in response to new food antigens whereas IgG4 antibodies are produced when the body is continually exposed to an antigen. If you’d like to understand the deeper science behind the production of IgG1 and IgG4 antibodies click here.

Therefore testing for IgG4 over IgG1 or total IgG is an advantage, as it leads to a reduced number of false-positives and allows for much more targeted, relevant results. It reduces the incidence of patients removing too many foods and doing so unnecessarily, therefore improving patient compliance and outcome. Basically, you are able to learn and understand the food items your body can tolerate, or, no longer tolerate and take steps to make changes with confidence.

What else do you need to know?

Advice from an expert Nutritionist, before you take your test.

  • What is Coeliac Disease?
  • Allergy & Intolerance prevalence in the UK
  • Food labelling
  • Post-test analysis: What is an Elimination Diet?

Coeliac disease is an autoimmune condition where the body mistakes the protein gluten, found in wheat, barley and rye, as a threat to the body and attacks it. This damages the lining of the small intestine producing inflammation and physical symptoms.

A staggering 44% of British adults now suffer from at least one allergy and the number of sufferers is on the rise, growing by around 2 million between 2008 and 2009 alone. Almost half (48%) of sufferers have more than one allergy (Mintel, 2010)

There are 14 foods which must be labelled and identified as ingredients on all pre-packed food:

Cereals containing gluten, crustaceans, eggs, fish, peanuts, soybeans, milk, nuts (almonds, hazelnuts, walnuts, cashews, pecan nuts, Brazil nuts, pistachio nuts, macadamia nuts), celery (including celeriac), mustard, sesame, sulphur dioxide/sulphites, lupin, molluscs

An elimination diet is the removal of foods, which have been identified as causing an allergic or intolerant reaction, from your daily diet.

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