If food sensitivities aren’t being addressed, a patient may eventually develop a condition known as “leaky-gut“. The immune system and associated antibodies in the blood are then triggered to mount an immune response to food particles, which the body considers to be a foreign entity and hence leading to a full-blown immune reaction and inflammation.
It is possible to measure and quantify IgG levels using a blood test that would indicate elevated antibodies in response to certain foods and food groups that are potentially causing harm. Elevated IgG levels may not always point to a food allergy and elevated levels are not always diagnostic. The value of this test lies in the proper interpretation of the results taking into consideration a number of situational and clinical factors. Naturopathic doctors are well qualified to administer and interpret these tests and are able to obtain very useful information from these tests to direct an appropriate treatment plan based on each individual’s circumstance.
Important facts about IgG Food allergy Tests:
DELAYED: Due to the slow onset of IgG reactions (hours to days after ingestion of food antigen), it is almost impossible to determine the exact cause of a food allergy using only an elimination diet.
DOSE: IgG reactions are dose-dependent; foods most frequently consumed or those consumed in large quantity are more likely to produce symptoms
HALF-LIFE: The half-life of an IgG antibody is between 23 and 96 days and it takes 5 to 7 half-lives for antibodies to completely disappear after reactive antigen has been removed. It could therefore take between 3 and 18 months for specific IgG antibodies to fall to the normal range.
Although an elimination diet is still the gold standard for food sensitivity testing, the time and diligence it takes to do a proper elimination diet is often discouraging. An accurate and reproducible food allergy test allows nutritious foods to remain in a patient’s diet while eliminating reactive foods thus making this test much more convenient and appealing.
How is the test performed?
The test is carried out in-office and is a relatively simple finger-prick test – a little puncture is made in the 2nd or 3rd finger, and a few drops of blood are collected into a microtainer vessel and sent to the lab. 80% of the antibodies in blood are IgG antibodies. This means that only a small amount of blood is sufficient to test a large number of foods. The procedure takes about 10 minutes to complete.
How do I prepare for the test?
There isn’t much preparation involved for this test but we do recommend that a patient be exposed to a diet involving a variety of potentially sensitive foods for a couple weeks prior to the test to minimize the amount of false negative results. Fasting is not required for this test.
As for the procedure itself, we usually we get the patient to run their fingers under warm water for a couple minutes prior to the procedure to ensure adequate blood flow to the finger. Massaging the fingers can also help.
How long does it take to obtain the results?
Test results are usually available 7-10 days after collection of the blood sample.
What is the cost of the test?
The cost of the test will depend on the antigens being tested. There are 3 panels that are most commonly used to determine food sensitivities:
120+ Food antigens – $275
200+ Food antigens – $379
160+ Vegetarian Food antigens – $315
Add-on Antigen (to 120+ or 160+) – $20
For the breakdown of antigens included in each panel please CLICK HERE. All food tests require a consultation by the naturopathic doctor beforehand.
Is the test covered by Insurance?
Typically the test is NOT covered by insurance but some extended health insurance plans do provide partial or full coverage. Please contact your insurance provider for more information on coverage of IgG Food sensitivity testing. Doctor’s fees are covered by your extended health insurance plan as naturopathic services.
To view a sample test report, CLICK HERE.