The word allergy is currently a buzzword. It is common to hear of people with food allergies.  However self-diagnosis, shady practitioners, and a genuine confusion between allergies and intolerances have perhaps made allergies appear more widespread than they actually are.
 
Allergies are reportedly one of the biggest money-spinners for the medical industry but is all of the testing necessary and trustworthy?
 
Contrary to popular belief actual food allergies are not that common, they are believed to affect around 2% of the adult population, and 5% of the pediatric population globally. All allergies are on the increase, with many citing the Hygiene Hypothesis and vaccinations amongst others as the cause. The number of ways of testing for allergies also appears to be increasing.
 
The Faithful: Standard and Accepted ways of Testing
There are three widely accepted ways of testing for food allergies: Skin Prick Test (SPT), the IgE Blood Test and the Oral Food Challenge (OFC).
 
The SPT is often the first step when allergies are suspected and is the cornerstone of primary allergy diagnosis. A tiny amount of the allergen is introduced to the skin, and the skin is pricked through the drop of the allergen using the tip of a lancet and does not hurt. It’s possible to test up to 25 allergies in one go
and results are highly reliable and swift.
 
The IgE Blood Test, also known as the RAST test, involves blood being drawn from the patient and analyzed for presence and levels of the allergen-specific IgE antibody – the universal maker for allergy testing. Hundreds of potential allergies can be tested in one go. Results must be interpreted by a doctor, and if necessary followed up with a SPT and/or OFC.
 
The OFC is never to be carried out at home. It should be administered by a qualified doctor; in case of complications from adverse reactions or anaphylaxis. As the name suggests the patient consumes an amount of the suspected allergen and is observed for signs of a reaction.  If previous results are ambiguous this test allows the doctor to verify or dismiss suspected food allergies.
 
The Flawed: Disputed and Ambiguous testing
Not the same as the IgE Blood Test, the IgG Blood Test looks for food-specific IgG and measures the IgG antibodies to various foods. IgG can be found in people without evidence of food allergies. There is no clinical evidence to support a link between food allergies and food-specific IgG levels.
 
There are a variety of allergy tests available through chemical analysis of bodily fluid and tissue, such as hair, blood and even fat. The samples are tested for numerous substances such as heavy metals and pesticides. The theory being people with high levels of these chemicals have a damaged immune system, resulting in a predisposition towards allergies. There is currently no clinical evidence to support this.
 
The Feckless: Disproven tests
Unfortunately many so-called allergy tests fall into this category, including VEGA testing, a form of electro-acupuncture used to determine allergies. The EU recently banned VEGA advertising, due to unsubstantiated results. Another example is Applied Kinesiology where the patient holds a sealed container with the allergen inside in one hand, whilst the practitioner tests the strength of the other arm. At any sign of weakness, the allergy is diagnosed. As Dr KP Leong of Tan Tock Seng Hospital states: “It is inexplicable how this relates to food allergies”. These are the two most common examples from a list of many.
 
As Dr Wen Chin Chiang of KK Hospital summarizes: “Accurate diagnosis of food allergy in children is of the utmost importance. Inappropriate food elimination is just as harmful. In cases of children with significant severe food allergies, strict elimination diet of that allergen is of the utmost importance in keeping that child safe”.
 
Vicky and Cris are mothers to two children (not the same two!) with severe food allergies. They write on all things allergy, family and fun in Singapore. They work with leading chefs to create allergy-aware meals for readers, as well as developing their own home-style recipes. They also hunt down places that are safe to eat at if you have a food allergy.