Have you ever wondered if you have food sensitivities? Maybe you have gone for a blood test and then been “diagnosed” with a food sensitivity? If so, be skeptical. Many food sensitivity tests do not address the biochemistry involved in food sensitivities.
Many “food sensitivity” tests claim that a simple blood test could identify foods that you are sensitive to. Are these tests credible? To answer this question, we first need to distinguish between Food Allergy Testing versus Food Sensitivity Testing. To do this, we need to identify the difference between an IgE vs non-IgE response.
Food allergies and sensitivities are reactions to food proteins. They may be categorized as immunoglobulin E (IgE) mediated (immediate) reactions vs non–IgE-mediated (delayed) hypersensitivity reactions, and mixed reactions. IgE-mediated reactions are the ones we worry about when we hear about a “food allergy”: flushing, itchy skin, wheezing, vomiting, throat swelling, and even anaphylaxis. These reactions can occur immediately following exposure and are the consequence of the interaction of allergens with our IgE response. The reaction leads to the rapid release of inflammatory chemicals that trigger a response which can be skin related (itching, swelling, rash) or a severe, life-threatening anaphylactic reaction.
Non-IgE mediated hypersensitivity reactions involve a variety of immune mechanisms (IgG, IgM, C3, C4, T-cell activation, phagocytosis, etc.) and non-immune mechanisms (pharmacologic, toxic) that trigger a proinflammatory and proalgesic mediator release from associated leukocytes (white blood cells). Released mediators produce corresponding physiologic effects (smooth muscle contraction, pain receptor activation, inflammation, mucus production, etc.) which leads to symptom manifestation.
Food sensitivities can be defined as any inflammation-generating reaction against a specific food or food component that does not involve type 1, IgE-mediated hypersensitivity OR food-related autoimmunity (think Celiac Disease). The inflammatory process associated with food sensitivities is significantly more complex than an IgE-mediated food allergy. Multiple triggering mechanisms and pathways, multiple classes of reacting white cells, a vast number of pro-inflammatory mediators, and a wide array of symptoms and conditions make sensitivities a highly complex category of adverse food reactions.
Beyond the IgE and non-IgE mediated reactions, there are other possible reactions to food, such as “food intolerance”. This includes conditions like lactose intolerance. Lactose intolerance is easily determined (although sometimes ignored until it gets worse) by the person who has symptoms after eating dairy foods, such as ice cream, cheese, milk, yogurt or butter. These symptoms often include diarrhea or constipation, excess mucous, bloating, gas, or stomach cramping.
So then, how do you test for food sensitivities?
You ask a professional (MD, DO, PA, RN or RD) who has become a Certified LEAP Therapist and uses the Mediator Release Test (MRT), developed by Oxford Biomedical Technologies.
The Mediator Release Test (MRT) is a functional blood test designed to identify sensitive foods and food-chemicals. It utilizes two advanced methods of measurement: flow cytometry and ribbon impedance. The MRT is the only blood test in the world that tests cellular end-point reactions to foods, chemicals, and other foreign substances, quantifying the degree of the inflammatory response and simultaneously determining which types of cells are reacting. The MRT provides the highest therapeutic value of any commercially available food–sensitivity blood test. The results are quantified (Re: green, yellow, and red bars) according to their level of reaction to help guide how the LEAP Immunocalm Diet is designed. The test has an excellent accuracy (Sensitivity 94.5%, Specificity 91.7%) and excellent reliability (split sample reproducibility consistently >90%).
Most “food sensitivity” diets rely on elimination. With the LEAP Immunocalm Diet, the focus is on what patients can eat, and includes foods they enjoy eating. Patients are involved in the process of choosing their foods, which results in greater levels of participation, enthusiasm, adherence, and satisfaction. I work with patients to help develop their LEAP Immunocalm Diet, which is based on the foods they are least reactive to, while avoiding foods (quantified through MRT Test) they are most reactive to. This is the ideal for patients suffering with the following conditions:
- Irritable Bowel Syndrome (IBS), Irritable Bowel Disease
- Heartburn, Small Intestinal Bacterial Overgrowth (SIBO)
- Fibromyalgia, joint and muscle pain, Arthritis
- Chronic Fatigue Syndrome
- Chronic Sinusitis
- Skin Eruptions, Eczema, Rosacea, etc
Sometimes when you see an advertisement promoting “food sensitivity” testing, it’s a test for Immunoglobulin G (IgG). IgG antibodies signify exposure to products – not an allergy or sensitivity. IgG antibody testing will identify what you ate recently – there is no correlation between an IgG test results and your ability to eat that food without distress. In fact, some research suggests IgG may actually be a marker for food tolerance, not intolerance. Given the lack of correlation between the presence of IgG and physical manifestations of illness, IgG testing is considered unproven as a diagnostic agent as the results lack clinical utility as a tool for dietary modification or food elimination.
Why would practitioners advertise that they test for food sensitivities, but use a test that does not measure food sensitivities? That’s a good question. Maybe they:
- Do not understand the biochemistry of food sensitivities?
- They don’t want to spend the money or time to study to become a Certified Leap Therapist (CLT)?
- They believe what the laboratory/testing company told them without conducting their own research? Let’s face it – there are lots of testing companies that would love me to use their tests $$$ – but I will only work with companies whose claims are evidence-based and scientifically sound.
More than not, I think that practitioners do not use the MRT Test and the LEAP Immunocalm Diet because they are pressed for time. They don’t have the time for the following:
- To sit with their clients to review the test results
- To research what foods are on the grocery shelves so they can review with you which foods and brands you can use to substitute foods you are sensitive to. It’s easier to just say, “Don’t eat what’s on this list.”
- To teach their patients how to make different meals by rotating the veggies, fruits, starches and protein they can eat
- To develop meal plans which outline what they can eat for breakfast, lunch, dinner and mini-meals
- To develop a rich resource of recipes to help clients figure out how to cook the foods they can eat
Do you have Irritable Bowel Syndrome, Irritable Bowel Disease, Gastroesophageal Reflux, Migraines, Fibromyalgia, Joint and Muscle Pain, Arthritis, Chronic Fatigue Syndrome, Chronic Sinusitis, or Skin Eruptions, Eczema, Rosacea? Have you been told that you can’t eat “X”, but never had any signs or symptoms (smooth muscle contraction, pain receptor activation, inflammation, mucus production, etc.)? Have you been told to eliminate certain foods, but never been told what to replace those foods with? Are you now micronutrient deficient because you have eliminated certain foods or food groups from your diet?
Together, we can work to eliminate the foods you are sensitive to and develop a plan drive to down inflammation so you can be your best self.