Hidden food allergies vs. hidden food allergens: What’s the difference?

Editor’s Note: In Healio Allergy/Asthma’s new column, “Food Allergy: Fact vs. Fiction,” Douglas H. Jones, MD, breaks down what’s true and what’s myth for a variety of topics related to food allergies. If you have a question you would like answered in this column, email Jones at rmaaimd@gmail.com or Sasha Todak at stodak@healio.com .

Do you know the difference between the two phrases “hidden food allergies” and “hidden food allergens?” They obviously sound similar, but they are quite different. What does each mean?

Hidden allergies

“Hidden allergies” is a term I hear almost daily from patients coming in for the first time or seeking a second opinion. Let me describe the typical scenario.

A patient has inconsistent gastrointestinal symptoms such as gas, bloating, cramping, pains, diarrhea or constipation. They may also experience brain fog, fatigue and/or joint pains they attribute to unknown foods.

Usually, one of two situations have led to them getting “food sensitivity or intolerance” testing.

First, they have done their own research online and found a home food sensitivity test that offers a broad panel of immunoglobulin G (IgG) tests to find their “hidden allergies” or “low-level food allergies” they do not know about.

Second, some doctors, chiropractors or naturopaths recommend these types of tests to patients. In my experience, many patients have been told these are tests that conventional doctors either don’t do or don’t know about and they have a more thorough approach.

The patient receives a list of multiple positive test results and told their body is creating a delayed immune response that may be contributing to food sensitivities/intolerances. The patient eliminates those foods for a period of time, and then reintroduces them weeks later.

As a side note, this line of thinking begs a question — if those foods were really causing a problem in the first place, why would it be recommended they reintroduce a problem shortly after it was apparently fixed by eliminating it?

A vast majority of the time, dairy and gluten are among the positive test results. The patient eliminates the foods and may feel better, initially, because many people will by avoiding dairy and gluten — especially in the United States where there is such a low quality of food.

The patient has now spent hundreds, if not thousands, of dollars to avoid foods that could be recommended they avoid with no testing involved as an initial step. Further, it is likely that they are unnecessarily avoiding foods, which can cause more stress.

Additionally, as I have repeatedly seen in this scenario with patients, I then wait for their next statement about the list of supplements they were inevitably sold — the ones with the “proprietary blends” and a “secret formula.” (Quick tip: Look for the supplement commercial anytime you are searching for a reputable podcast or book.)

The laboratory company (and the doctors that are associated with them) have creative websites. They will go into the basic science of allergy and immune responses. It looks credible as what they describe in general terms about the various allergic reactions is proven and well-known. They will then quote popular doctors to try and enhance their credibility further.

What they don’t publish, though, are the multitude of studies showing that these tests do not necessarily show that the immune response (food-specific IgG production) does not correlate clinically with a patient’s symptoms. Further, they do not comment that the tests have not been shown to prove it is an allergic reaction that is causing food sensitivity. In fact, if anything, it likely signifies tolerance or exposure. For instance, when we do oral immunotherapy to treat legitimate potentially life-threatening allergies, we can prove that food IgG increases as the reaction threshold increases and tolerance is achieved.

Food allergies aren’t hidden. They are obvious. Ultimately, it is between the doctor and patient to make the best decisions possible on how to approach food allergies, sensitivities and intolerances.

In this case, I suggest looking beyond the headlines and exercise caution with food sensitivity or intolerance tests as I have yet to see any of them to be a validated measure no matter what the marketers say. I am not saying that people don’t have food intolerances or sensitivities — many people do. What I am saying is these tests do not give the results to which they allude.

Hidden allergens

The term hidden allergens, on the other hand, is very important. This means that a food or product may contain certain common allergens (milk, eggs, soy, wheat, peanut, tree nuts, sesame, etc) that you may not be aware of or are not on a label. This can be very dangerous to a person with a legitimate potentially life-threatening food allergy if they do not know or aren’t aware of the ingredients and that they may be at risk.

A few examples:

• Dog food may contain peanut products and if your dog licks you after eating, you could react if you are unaware.
• Some macadamia nut cookies actually contain other nuts such as cashews.
• Different brands of play dough and modeling compounds may contain wheat.
• Tree nuts and coconut are in many skincare products.

If someone is not aware or made aware that the food to which they are allergic is in a product, then that can have dire consequences for that patient if they are exposed. This underscores the importance of appropriate product labeling, and also having an emergency plan in case an accidental exposure happens causing a serious reaction.

This is another reason patients should always carry an epinephrine injector with them in the event they come across a hidden allergen. I always tell patients, “Act like the military and prepare for worst-case scenarios, not most likely scenarios.” Be prepared, not scared.

The key takeaways:

• “Hidden allergies” is a made-up term and, if you hear this phrase from a care provider, consider a second opinion as you are likely being sold something. Look beyond the headlines.
• Hidden allergens are a legitimate risk to those with life-threatening food allergies. A food or product may contain an allergen and the person may not be aware it is there.

References:

For more information:

Douglas H. Jones, MD, FAAAAI, FACAAI, is cofounder of Global Food Therapy, Food Allergy Support Team and OITConnect, the director at Rocky Mountain Allergy at Tanner Clinic, and a Healio Allergy/Asthma Peer Perspective Board Member. He can be reached at rmaaimd@gmail.com.