Why You Probably Shouldn't Waste Your Money On Food Sensitivity Testing

Let’s face it, whether you are a millennial or a Gen X or honestly, born in pretty much any generation, you can’t help but enjoy at least some of the amazing advancements in technology. Whether it’s never leaving your car when picking up your groceries, getting that one item you desperately need off of Amazon or streamlining your shopping, technology has definitely created a major need for quick, easy and convenient services. Now, more than ever, we also expect the same in other areas of our lives, including our health care.

As consumers, we want to take a proactive approach to our health, and don’t worry the health and wellness industry hears you loud and clear. In fact, now more than ever, you can access a variety of testing options straight from the comfort of your home. One of the most commonly ordered tests consumers are buying are food sensitivity tests. But, what is a food sensitivity test really about and is it actually worth the hype? What’s the difference between a food allergy and a food sensitivity and do you need to spend hundreds of dollars on fancy tests to really get to the root cause of your symptoms? Let’s dive in.

The truth is, there are several validated, standardized and accepted tests for the evaluation of both food allergies and food intolerances. Unfortunately, there are also a large number of other tests and test companies that promote a variety of “tests” that are not validated or standardized. In other words, the results they provide can not be determined as accurate or reliable. So, what is an adverse food reaction and what is the difference between a food allergy, food intolerance and food sensitivity?

An “adverse food reaction” can be divided into two major categories, those that are immune-mediated and those that are not. The term “food allergy” generally refers to the immune-mediated reactions which result in the production of a particular antibody known as immunoglobulin E (IgE). Now, although we could test for food allergies using IgE antibody testing, the presence of an IgE antibody to a suspected food is only one piece of the puzzle and is not sufficient for a proper diagnosis. So, even if you do order an IgE food allergy test and have a positive response to, let’s say dairy, this isn’t enough to diagnose you with a food allergy. In fact, a comprehensive history and physical exam, as well as an oral  food challenge is often required. Now, since food allergy reactions can vary in severity and can lead to severe symptoms that may require immediate medical attention, it is very important to work with an allergist when performing a food challenge. Don’t try doing this type of  challenge at home. This is a huge limitation to direct-to-consumer lab company testing. They provide you some but not all of the information you will need to treat your symptoms.

There are also non-IgE-mediated food reactions like reactions to wheat in patients with celiac disease. These types of reactions are not immune mediated and are better termed as food intolerances. Food intolerances are associated with a patient’s inability to digest or metabolize certain food substances. Another example of a  food intolerance would be a lactose intolerance. It is also important to mention that there is a unique type of gluten sensitive patients who are known to have non-celiac gluten sensitivity(NCGS). Non-celiac gluten sensitivity can cause similar symptoms to gluten-containing foods however, in the absence of a true celiac disease or wheat allergy. Although researchers still have much to learn about the mechanism behind non-celiac gluten sensitivity, there are currently limited reliable biomarkers and tests available to confirm NCGS. Currently, diagnosis of NCGS is made with a double-bling placebo controlled gluten challenge, not a serum blood test. Now although gluten-free products and advertisements are on the rise, it is important to remember that only about 1% of the American population (about 1 in 133 Americans) are said to have celiac disease. Researchers believe that there is a potential for higher incidence in patients with non-celiac gluten sensitivity, however the numbers are still well below the range currently advertised by your social influencer or food sensitivity lab company’s marketing team.

Standardized Diagnostic Tests That Are Actually Accurate 

Since many adverse food reactions can be associated with an immune response, testing is still very important and allows us to demonstrate the IgE antibody response we are looking for. This is where a skin prick test and serum specific IgE antibody test can be seen as well validated and standardized tests we can use when evaluating your adverse food reaction. That being said, since not all adverse food reactions are immune mediated, additional testing may be necessary. For example, just because you don’t have a positive result from an IgE antibody test for wheat doesn’t mean we can rule out celiac disease. Instead additional tests including anti-tissue transglutaminase (tTG)- IgA testing is needed. If you are positive for anti-tissue transglutaminase, although the diagnosis for celiac disease is extremely likely, the gold standard of diagnosis is a intestinal biopsy.

Unproven or Disproven Allergy Tests to Watch Out For 

According to the US National Institute of Allergy and Infectious Disease, one of the most widely available but also unproven tests available to consumers is IgG food testing. This is your standard “food sensitivity tests” you have either seen in a targeted ad, used by an influencer or even available at your local pharmacy or grocery store. Interestingly, similar to IgE antibody testing, there are quantitative ways we can measure IgG immune mediated responses to foods. The methods of testing are standardized and there is no reason to believe that they do not provide accurate measurements. (This is something many of these direct-to-consumer lab companies will share in the marketing). The problem, however, is that the clinical use of this information has not been established. In other words, IgG tests will likely show a response to particular foods because we naturally have an immune response to certain foods, but this doesn’t actually mean there is a problem. Think of IgG immune response as a way for your immune system to collect a memory of a particular food you have eaten. It does not automatically mean you had a bad response, it just means you had a normal immune response.

In fact, many of these companies rely on a theory that the presence of food-specific IgG, (or IgG4) antibodies could lead to the formation of an immune complex and a type III hypersensitivity reactions or that some patients are more sensitive to the inflammatory processes caused by these antibodies in otherwise healthy patients. However, this theory is flawed because, unlike IgE antibodies, the production of IgG antibodies to foods is normal!

Two of the most common unproven tests to be cautious with include antigen leukocyte antibody test (ALCAT) and the mediator release test (MRT). In fact, an independent review of the ALCAT test concluded that yes, the actual methodology used to measure cell volumes was valid, however there was no data available that correlated the results with true clinical improvement in patients. In other words, data is great, but it’s also what you do with it that matters.

Hair analysis is another commonly promoted testing option for food sensitivities. And although hair analysis is well accepted as a way to detect heavy metal toxicity, the same mechanism can not be directly applied to food sensitivities.

Why This is Such a Problem For Your Health 

So not only are many of these tests not validated or even disproven but they provide consumers with a sense of ease that they found the “root cause” of their symptoms, when in fact, this could actually delay a true diagnosis. Patients are also being provided with long lists of foods to which they have generated IgG antibodies are being told to eliminate all of these foods in order to resolve their symptoms. Some may say, “Well, I eliminated all the foods the tests told me to and now I feel better, so how come this isn’t valid”. It’s not to say your symptoms or experience isn’t validated but chances are in the process of eliminating so many of the foods listed, you likely also are eating less processed foods, less sugar and you may also be someone who has also made other health related lifestyle changes including incorporating more exercise or making sleep a priority. The point is, what we eat, the food we ingest absolutely has a physical and physiological effect on our health, however cutting out otherwise healthy foods because an IgG test told you to isn’t the right solution. The other major problem with extreme restrictive diets is that not only are unsustainable but they can absolutely lead to disordered eating behaviors. At NMD Wellness of Scottsdale, we have seen this time and time again, and believe in helping patients re-establish their relationship with a healthy well balanced diet that is evidence-based. Do we make dietary modifications for our patients, absolutely. Do we rely on unproven tests to do so, no. As previously mentioned immune mediated adverse food reactions is only one of the categories of reactions, evaluating your digestion and metabolism is just as important when addressing your symptoms.

If you are suffering from GI related symptoms and are interested in addressing the root cause, we highly recommend consulting with your doctor for a proper evaluation. At NMD Wellness of Scottsdale, we help provide patients with standardized diagnostic testing, digestive support for non-immune mediated responses and dietary plans that actually provide patients lasting results. No need to waste your money on unproven testing options. 

About the Author: Meet Dr. ZenAlissia Zenhausern- Pfeiffer, NMD, FABNE, (commonly known by her patients as Dr. Zen), is a licensed naturopathic doctor board certified in naturopathic endocrinology and the founder of NMD Wellness of Scottsdale, a premier naturopathic medical practice that focuses on helping women to take a proactive approach to their hormone and fertility health. Dr. Zen has been featured as a lead expert in Forbes, Shape Magazine, and Instyle and is deeply passionate about bridging the gap between traditional and natural medicine in the world of fertility. She works with a variety of hormone related issues including PCOS, endometriosis and unexplained infertility. Her goal is to help more women get back into the driver’s seat of their own health to make lasting transformational changes to their health to bring more cute and adorable babies into this world. Read More About Dr. Zen...