Many people now report having a food allergy and are understandably keen to get a proper diagnosis, but how do you get an accurate allergy test?
Some of the symptoms of food allergies can involve digestive problems such as stomach pain, vomiting and diarrhoea. However, these symptoms are not very specific and may be mistaken for other conditions such as irritable bowel syndrome.
When an individual has a food allergy, their body mistakenly creates antibodies (IgE – antibodies) in response to coming into contact with that food. This then can result in the symptoms described above.
It is difficult to say exactly how common a food allergy is within the UK as the data which has been collected is not very consistent. Luckily we do know that allergies are less common during adult years (1).
Many people will claim to have an allergy after paying for an ‘allergy test.’ While it is understandable that individuals want to get answers, these tests are highly inaccurate, expensive and may have absolutely no scientific backing.
- Basil histamine release/ activation
- Facial thermography
- Alternative blood tests (leukocytotoxic tests)
In practise, dietitians often see nutritional deficiencies or malnutrition caused as a result of an individual avoiding many foods. Sadly, they often do not get any symptom relief at all.
How Do You Get a Correct Allergy Test?
Firstly, we need to understand that allergies can be categorised into 3 different types;
- Non-IgE mediated
- IgE mediated
- Mixed type
1.IgE & Mixed Type
The gold standard for allergy testing – a specialist assessment of your medical and symptom history, an allergen specific IgE serum blood test and a food exclusion diet.
For IgE mediated allergies, a skin prick test may last be used. But, only alongside your symptom and medical history. Again, this would be followed by a food exclusion diet.
The reason for this long winded format is that firstly an allergy has certain patterns which a specialist can check from your medical history and rule out other possible causes – you may not need any further testing at all. The blood test, while a good tool, actually shows an ‘allergic sensitisation’ but not necessarily an allergy (1).
Finally, the exclusion diet, followed by a reintroduction period further improves that accuracy of the of the overall diagnosis (1). It is important to note that you must do this under a dietitian as so many factors can cause digestive symptoms and you will not have the clinically expertise to decipher if these are allergen related or not. In addition, the dietitian can advise you on timing, quantities and wash out periods between reintroductions.
2. Non-IgE Mediated
There are some ‘non-IgE’ mediated allergies where there are currently no blood tests for and so a medical history, symptom evaluation and exclusion diet is used to find the best diagnosis (1). Non-IgE mediated allergies are often indicated in those with delayed reactions or who appear to have no pattern in their symptoms.
What is an Elimination Diet?
An elimination diet is a diet where 1 or several allergens are excluded from an individuals diet for a set period of time. This is not a diet for life as such, but more of a way to diagnose. Following the elimination period comes a period of food challenges or reintroduction phase and this is where you confirm your allergy.
It is important to note that you must NOT attempt this diet alone. There are many blogs online which can talk you through a similar process but they often suggest avoiding foods which are not common causes of allergies and you do not have the expertise to decipher any results. Not only this but missing out that expert help may mask over an underlying medical condition such a coeliac disease which is not an allergy. In this case, you may go on to get osteoporosis as you miss out on the care you require.
It may be tempting to avoid reintroducing potential problem food but continuing on an elimination diet can lead to malnutrition and nutritional deficiencies as you unnecessarily avoid multiple foods which may not be the cause of your symptoms (1).
If you feel that you may have an allergy, then you must speak to your doctor or a specialist registered dietitian. Paying for tests in your local health shop or buying services online is just a waste of money and following this advice could make you very unwell.
If you would like to book an appointment to discuss a possible food allergy, please contact me on +447827817013 or firstname.lastname@example.org
Please note, if you think you have an allergy, you must report this to your GP who will get you on the correct path to a safe diagnosis. Attempting to tackle an allergy on your own, may result in death as some reactions are life threatening.