Food Sensitivity Tests: Facts and Fiction
Lately, Food sensitivity tests have been in the news. They are portrayed as being harmful to clients and their family. Your own doctor may have said the same to you. You wonder. What’s that all about?
Here is what’s fact and fiction from my experience and training as a German-trained and licensed Allergist:
Below, I will talk about 5 commonly asked questions:
What is the difference between a “true” food allergy and a “food sensitivity”
The first of the two main types are Immediate type allergies (the “true” allergies).
These are IgE (a certain Immunoglobulin) mediated and lead to a reaction within 30 min or less of ingestion of the offending food. The typical reaction is swelling of the lips, tongue or throat, itching and hives on the skin, breathing difficulties, wheezing or even an immediately life-threatening anaphylactic shock. Sufferers should always carry an epi-pen which may help save their lives.
This allergy type typically gets tested with a skin test or a blood test (RAST) which tests the IgE antibody level. Since the reaction is often immediate, it mostly is easy to determine the allergen this way.
Delayed-Type “Allergies” – Sensitivities
The second major type of “allergies” are delayed-type allergies. There are different kinds of those, the most well known are the “Sensitivities or “Intolerances”. These are IgG-mediated and lead, if any, to a reaction only 12-72 hours after ingestion of the offending food.
They are said to cause a “subclinical” reaction, leading to a chronic and festering inflammation and possibly contributing to mysterious diseases like autoimmunity and other chronic illness.
How can we test for the delayed-type allergy or a food sensitivity?
There are different tests for these delayed-type food reactions.
Some are less proven, like the muscle test where you hold the food or even just think about the food and the testing person tries to figure out whether this food makes your muscles weaker. Or a test about “radiating energy” with mysterious frequency computers, holding vials with the food or food extract in your hand. Do they never work? It depends. These are highly subjective and are based on the testing person’s experience and their best guess.
Then there are the blood tests, either as a finger prick or a blood draw from a vein. These blood tests test for levels of the IgG, the Immunoglobulin G, antibodies, which are said to be causal for food sensitivities.
Skin Patch tests are sometimes, although rarely, done, because they rarely ever lead to a measurable result and are inconvenient and have to be read several times within the 72 hour window.
Is Food Sensitivity Scientifically proven or not?Well, in the typical sense it certainly is not.
Science has brought us a long way in finding single causes of illness and finding single and highly effective treatments. Scientific standard is a so-called double blind study, where neither the researcher nor the patient knows whether they are getting the “real” thing or a “sham” thing, something like a placebo, a sugar pill. This tests for the difference between the belief of the patient – which is very powerful – and the actual effect of the drug or other agent they are testing. This kind of study makes sense to prove or disprove a hypothesis on something that is not very individual, like if a drug works or not.
But: The more complex the causes and solutions for a condition are, the less feasible is it to apply these rules. Do we need new ways to study complex and chronic issues? Absolutely!
Is there a good and proven way to do so? Not yet…
For practical and ethical reason, a double-blind study is not possible to prove a food sensitivity. It would involve using fake tests and neither the clinician nor the client knowing if the test is real or not and either suffering the consequences of following a diet that can be potentially harmful or not following a diet that may be helpful.
and causality is hard to prove, if at all possible.
And conventional science does not count in case studies, since they go by “averages”. By definition, most people are not average, but do fall within a range between two standard deviations of “average”. People are all individuals!
But: Please don’t think that I want to discount science’s merits at all. The scientific method has brought us so many improvements in our life and health like antibiotic treatments, anesthesia - allowing for nearly painless life-saving surgeries, certain life-preserving vaccinations, life-saving treatments and medications like insulin and more.
Can a food sensitivity test be dangerous?
Well, not the testing process itself, but the way the results are communicated and applied can very well lead to dangerous and unintended consequences.
False-positive and false-negative results
Like with most tests, there are false-positives (it shows a reaction even though there is really not) and false-negative ( which means, the test comes back negative, although there is a reaction) results.
What does this mean?
This means, that just doing the test and telling the patients or clients to avoid all foods that come back “positive” is not appropriate and can lead to dangerous malnutrition, especially if applied to a growing child by a well-meaning mom.
I’ve had clients tell me that after a practitioner told them that they were allergic to foods like dairy, gluten, (which everyone seems to tell you nowadays) and a few more, they had no idea what to eat now.
People may develop an anxiety around food and compulsively watch what they eat and their reactions to an extent that equals an eating disorder, which is very unfortunate and can lead to serious health issues worse than the ones that originally led to the test.
Can a food sensitivity test be helpful?
Does this sound like a contradiction?
Here is what I found to be true and what we need to do:
The only correct way to work with such a test is to meticulously correlate them with a symptom and food diary and then follow-up after elimination of the suspected foods with appropriate access to alternative nutritional options, giving the client meal plans, shopping lists and recipes to follow to ensure they get a wholesome nutrition – and then a follow-up or maintenance phase.
Sounds complicated? It is!
This all involves a considerable investment of time, money and work by both the involved client and their family and the practitioner - and is often not done.
I found, if done in the right way with the right attitude - and while continually educating clients about the risks and cautions applicable to a food sensitivity test, this test can be extremely helpful to narrow down a complex disease issue and hint to possible offending foods.
If correctly correlated with the history, symptoms and food diaries, food sensitivity tests can enormously shorten the time to find out what – if any - food is contributing to a certain illness.
Compare this with elimination diets, that are tedious to follow, may lead to worse malnutrition and often do not lead to tangible results because they fail to eliminate one or more reactive food.
In my practice, in the context of a rigorous Turn-Around-Assessment, I’ve seen excellent results and improvements applying this kind of a food sensitivity test to an individual client’s history.
I’ve seen excellent results and improvements applying this kind of a food sensitivity test to an individual client’s history in many chronic inflammatory conditions.