By Jaime Coffey Martinez, MS RD | 02/20/2018

Food Sensitivity Testing

Food Sensitivity Testing

According to various studies, an estimated 20-25% of the U.S. population are affected by food sensitivities and that estimate may be much higher.

Unlike food allergies, a food sensitivity reaction is often delayed. Symptoms can present hours or up to 3 days after consumption, making it very difficult to draw a connection between the food and the reaction. The delayed response can also cause individuals to suffer from unexplained health conditions for months or years.

Symptoms caused by food sensitivities are wide-ranging and often include multiple systems in the body such as digestive, respiratory, central nervous system, musculoskeletal, dermal, metabolic and cardiovascular. More common health complaints from food sensitivities include irritable bowel syndrome (IBS), migraines, ADHD, acne, autoimmune disorders, joint pain, eczema, weight gain /obesity, asthma, depression/anxiety, and chronic infections which are also very different than a typical allergic reaction to food.

What is food sensitivity testing?

Food sensitivity testing is a blood test that measures IgG antibodies in the blood to determine the level of sensitivity/inflammation to foods. It is often confused with food allergy testing, which measures IgE antibodies in the blood in response to histamine and cytokine release.

An easy way to explain the difference is using colors. Think of an allergy as being black or white. One is either allergic to it or not. Food sensitivity is a giant grey scale. A mild sensitivity may be a light grey whereas a severe one can be very dark grey but never black.

Testing involves a blood draw and the lab measures the number of IgG antibodies present in the blood against a number of foods. The most common food sensitivities include wheat/gluten, cow dairy, soy, nuts, corn, eggs, and fish. Tests can measure antibodies against 200+ foods

Results classify foods using a scale of 0-3 or 0-5 (depending on the lab) with the number corresponding to how low or highly reactive one is to the food.

How reliable is food sensitivity testing? 

Reliability of the test can be a challenge in some situations.

It is important to note that IgG antibodies are generated in response to a trigger but are continuously metabolized/broken down by the body. As a result, individuals who have eliminated certain foods from their diet may not have enough or any IgG reactivity when tested. This can be confusing for clients, as they know they are sensitive to a food, yet the test does not indicate it because the antibodies are no longer present.

Clients may also have an elevated reactivity to a food that they do not consume, which can be the result of cross-reactivity from an unknown exposure. Cross-reactivity occurs when the proteins in one food are similar to proteins in another and the result is the immune system sees it as the same food and reacts. The small intestine can be damaged and absorption of nutrients is affected as well as clients being symptomatic to foods that they didn’t believe they were sensitive too.

Cross-reactivity can also cause false positives for food sensitivities causing clients to remove foods that they are not sensitive to but instead symptomatic to a cross-reactive food. For example, there are 6 foods that our bodies can confuse for gluten because of their similar protein structure: dairy, corn, millet, rice, yeast and oats and this is just cross-reactivity to gluten! As one can see, this can become very confusing and frustrating for clients and have us question the reliability of the test.

Some propose elimination diets instead of food sensitivity testing. What are your thoughts?

There are benefits and limitations to following an elimination diet instead of testing.

Cost is clearly a huge benefit of an elimination diet as well as an immediate action instead of getting the blood test done and waiting for the results. Elimination diets are an easy, self-exploratory way to determine sensitivity. To follow, one eliminates a food(s) for a minimum of 4-6 weeks and waits to see if symptoms resolve.

A limitation can be if one removes more than one food at a time, it can be difficult to determine if there is sensitivity to one, both or all foods eliminated. In addition, while the foods I mentioned are the more common sensitivities, clients can present with a more obscure sensitivity and without testing, this can be missed.

IgG testing can also be overwhelming if dozens of foods are reactive and can create an unhealthy relationship with food.

Also, depending on the degree of sensitivity/reactivity, the recommended elimination time may be longer than 4-6 weeks and a short elimination may not be long enough to heal.

If one opts for an elimination diet, working with a licensed registered dietitian is recommended for assistance in diet protocol as well as reintroduction/challenge phase.

What food sensitivity lab do you use with your clients?

There are many different food sensitivity tests available to self-purchase without physician orders. ALCAT, ELISA, MRT and RAST tests are some of the most common tests to measure IgG or IgE antibodies to food sensitivities. On my website, I recommend clients to as they offer a variety of tests and price points.

How has food sensitivity testing helped some of your clients?

I use a multi-step approach to helping clients navigate the results of food sensitivity testing. If an individual tests positive to 10+ foods, I help clients rank and group foods with the highest reactivity and eliminate those foods for a specific amount of time pending results. Lower reactive foods are addressed through clean eating and supplementation that focuses on healing the gut. This approach helps clients minimize anxiety and provide clarity relating to test results.

In my practice, clients who complete food sensitivity testing and then follow an elimination diet and protocol to heal their gastrointestinal tract, experience improvement or total resolve of their symptoms as well as increased energy and improved body composition. For many, it has been the missing piece of the puzzle for improving their health, well-being, and weight. Here are two client success stories from my practice:

Success Stories

Client A presented with difficulty losing weight, chronic sinus complaints and frequent sinus related infections despite following what many would consider a balanced, healthy diet and lifestyle. After a thorough consult and no testing, I recommended she avoid cow’s dairy for 4-6 weeks as I suspected a dairy sensitivity. After 2 weeks, her sinus complaints completely resolved and the scale started moving again (after 3 months of a plateau). After 6 weeks, she decided to try a dairy challenge and reintroduce. Within 1 day of reintroducing, her sinus symptoms returned along with general malaise. She opted to avoid dairy for a minimum of 6 months and continue to focus on healing the gut.

Client B presented after testing positive and highly reactive to wheat, gluten, rye, cows milk, cheese, and yeast and several foods that were class 1. She had documented gastrointestinal complaints, headaches, chronic eczema and joint pain and she was following a standard American diet. I opted to group her foods and suggested she avoid gluten and cow’s dairy as well as sugar and follow a low carbohydrate, minimally processed diet. As for supplementation I recommended she add a quality probiotic and L-Glutamine. Within 10 days of avoiding the above, her symptoms began to improve and chronic complaints that she lived with for years were significantly resolved by the fourth week.

About Jaime

Jaime Coffey Martinez, MS RD is a registered clinical and integrative dietitian that practices in the Washington DC metro area and is owner of Nutrition CPR, LLC a nutrition consulting company providing both one to one nutrition coaching and corporate nutrition and wellness programs. Jaime coaches her clients on the importance of choosing real, nutrient dense foods that will nourish the body, optimize health, and help clients achieve their personal goals. 







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