The 88 Food Allergy and Sensitivity Test (FAST) is a comprehensive panel measuring 4 distinct immune reactions, IgE, IgG, IgG4 and complement (C3b/d), to 88 common food antigens.
Food allergies and intolerances are rapidly becoming recognized as significant triggers for initiating immune-mediated responses and inflammatory symptoms in individuals.
Metaflammation (a new term used in the clinical literature) is a chronic state of hyperimmune issues that include increased production of inflammatory cytokine release. Current literature supports that food allergies, intolerances and sensitivities are directly tied to metainflammatory sequelae and the release of GUT mucosal IgE and IgG type antibodies.
Screening for food allergies, sensitivities, and intolerances helps determine where your patient "is" regarding underlying gut/immune responses. Identification of offending foods can provide valuable insight into dietary suggestions to help patients with their inability to overcome chronic inflammatory processes even with currently accepted treatments.
Food intolerances/sensitivities should be assessed as a baseline to promote health and well-being. Chronic inflammatory conditions like autoimmunity, skin conditions, allergies, IBS, colitis type 2 diabetes and insulin resistance, thyroid issues, cardiovascular issues, cognitive decline, and sex hormone imbalances are all areas where knowledge of food allergies and sensitivities could add tremendous insight to management of these conditions.
IgG-mediated food sensitivities and intolerance issues are much more common than true food allergies.
Antibodies are proteins made by the immune system that attack antigens such as bacteria, viruses, and allergens. They can become confused or cross-reactive and begin attacking foods instead.
IgG (IMMUNOGLOBULIN G, TOTAL): are antibodies that provide long-term resistance to infections and have a much longer half-life than an IgE allergy. This food sensitivity can be more subtle than allergies, and many people live with it for years, if not their entire lives.
IgG symptoms typically occur within 3-72 hours after the offending food was ingested and will create ongoing inflammation that can worsen most conditions. Sensitivity symptoms range from:
The degree and severity of symptoms vary significantly from person to person because of genetic makeup. Eliminating IgG-positive foods may improve symptoms of irritable bowel syndrome, autism, ADHD, cystic fibrosis, rheumatoid arthritis, and epilepsy, as demonstrated in numerous clinical studies. It is essential to get tested for food sensitivities to know what foods work for the patient's body and what foods don't. If you only look at allergies or IgE, you will miss the IgG-mediated symptoms, creating an incomplete picture.
IgG4 (IMMUNOGLOBULIN G SUBTYPE 4): is another antibody produced in the body to fight infection. IgG 4 is used in allergy therapies to help neutralize the reaction of IgE. This is because of its potential to decrease histamine responses by blocking IgE from attaching to receptors.
Levels of IgG4 are beneficial up to a point, as they block IgE or allergic reactions and result in immune tolerance to foods.
Too much IgG4, however, causes immune-mediated conditions known as
IgG4-RD that typically affects multiple organ systems in the body. IgG4 is highly associated with autoimmune conditions. For these reasons, it's essential to know the levels of IgG4 in the body to maintain a correct balance. An example of a tissue susceptible to higher levels of IgG4 is the esophagus, resulting in Eosinophilic Esophagitis. IgG4 also interferes with the thyroid, contributing to autoimmune thyroiditis, and can also cause IgG4- Related Diseases (IgG4-RD) of the ovaries and prostate.
IgE (IMMUNOGLOBULIN E): Allergies are the immediate responses to a foreign substance that has entered the body via food or inhalation. IgE allergies can cause severe symptoms like difficulty breathing, swelling, and hives. In more serious cases, IgE reactions can lead to anaphylactic shock. Our test measures the serum level of IgE, one of the four subclasses of antibodies.
High titers of IgE are associated with allergic reactions when the immune system overreacts to a food or environmental antigens such as pollen, pet dander, or parasitic infections.
C3d/b (COMPLEMENT COMPONENT 3): are proteins of the innate immune system which can be activated by microorganisms in the absence of an antibody.
When C3d/b is activated in response to an antigen, the C3 portion attaches to the antigen. This activation, even though independent, will amplify the reaction that occurs with total IgG, significantly increasing inflammation and sensitivity symptoms. This same reaction that was designed to amplify inflammation to microorganisms can be triggered in response to foods. If complement is present, it will amplify
an IgG reaction as much as 10,000-fold. Therefore, tests that only measure IgG may miss the reactions to foods that are most clinically relevant. Complement Explained.
No antihistamines or steroids 72 hours before taking the test.
We recommend consuming a small amount of food you have not eaten within 72 hours of taking the test if medically possible. For example: If you have not eaten Gluten in a period and are NOT Celiac, eat ½ a slice of bread within 72 hours of your blood draw.
The 88 Food Allergy and Sensitivity Test (FAST) is a comprehensive panel measuring 4 distinct immune reactions, IgE, IgG, IgG4, and complement (C3b/d), to 88 common food antigens.
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