Food Allergy and Food Sensitivity Testing

At Boulder Natural Health we offer food allergy and food sensitivity testing for 144 foods including the most common food allergens–wheat, gluten, eggs, soy, milk, cheese, nuts, tomatoes, citrus fruits, and 6 spices through US BioTek Laboratories. This test helps to determine specific food allergies, the level of allergic reaction–high or medium or low, and the appropriate diet to alleviate allergic symptoms.

To see a sample report from US BioTek, click here.

What is a food allergy?

Our immune system’s job is to identify and destroy germs including bacteria and viruses.  In the case of a food allergy, the immune system becomes imbalanced, irritated and inappropriately creates an immune attack against a food.  The European Academy of Allergy and Clinical Immunology (EAACI) defines a food allergy as an immune system mediated, clinically evident reaction to a food.

Much of our immune system resides in the lining of our gastrointestinal tract.  The GALT (Gut Associated Lymphoid Tissue) is regarded as the largest immune organ and its job is to mount an immune response against foreign invaders, usually bacteria and viruses.  When there is inflammation in the digestive tract, usually secondary to a combination of toxic environmental factors, overuse of antibiotics, nutritional or microbial imbalances, the immune system can get irritated and create an immune attack against food.  This attack can involve the production of antibodies including IgE, IgA, IgG and IgM, which can be measured in a blood sample to determine which foods are irritating the immune system.  Food allergies are usually divided into IgE- and non-IgE reactions.

What is the difference between an IgE-mediated and non-IgE-mediated allergy?

An IgE-mediated allergy involves the production of IgE antibodies to certain foods or inhalant allergens. Symptoms usually occur immediately after exposure or within 15 minutes. A late phase reaction may then occur 4-6 hours later and persist for days with increased edema and inflammation.

The classic reaction occurs when IgE antibodies, bound to specific immune cells (mast cells), recognize and bind to the allergen. This interaction triggers the release of chemical compounds and histamine from the IgE-bound cell. The release of histamine can trigger symptoms such has watery eyes, runny nose, stomach cramping, diarrhea, skin rash, swelling and anaphylaxis.

Non-IgE-mediated allergies involve antibodies other than IgE (e.g.: IgG, IgA).  Symptoms of an IgG-dependent food reaction may occur hours to days after the exposure to the food or meal.  The IgG antibody may bind to the food antigen and form an immune complex. These complexes can deposit in various tissues in the body and trigger inflammatory reactions.

What is an anaphylactic food reaction?

An anaphylactic reaction to a food is a life-threatening condition that causes swelling and constriction of the airways. It is an IgE-mediated hypersensitivity reaction and occurs immediately after the ingestion of the culpable food. This condition requires immediate medical attention.

What causes a food allergy?

The underlying reasons for allergies vary from person to person. Possibilities may include stress, trauma, underlying disease, genetic predisposition, compromised microbial gut flora, and poor immune function.

How is an allergy identified?

Serum from a blood draw or whole blood from a finger stick may be used to measure immediate and delayed allergies. US BioTek uses state of the art ELISA methodology for FOODStats antibody assessments. ELISA stands for Enzyme-Linked Immunosorbent Assay. ELISA is a semi-quantitative screening tool for the detection of IgA, IgE and IgG antibodies in serum.

Are there any food restrictions prior to testing?

No. It is advised to maintain usual dietary habits and consume a variety of foods before testing, if possible. Prolonged avoidance of certain foods may show low serological values.

It is strongly advised to avoid any food that may have resulted in a previous adverse reaction or anaphylaxis.

Are there any medication restrictions prior to testing?

Immunosuppressive drugs such as oral or intranasal corticosteroids (prednisone, beclomethasone, fluticasone, triamcinolone), and topical cortisone suspensions and creams, may affect test results. The suggested time period to abstain from these is 4 weeks.

What is an allergic cross-reaction?

Cross-reactivity is an important consideration in allergy assessment. When the immune system mounts a response to a protein of similar moiety to a known allergen, adverse reactions may occur.  One example is sensitivity to latex shows extensive cross-reactivity with certain foods including banana, avocado and mango. Natural rubber latex is a common ingredient found in many products including balloons, appliance cords, hearing aids, swimwear, condoms, rubber bands, and medical and dental supplies such as masks, gloves, syringes, catheters and bandages.