What are we testing?

Immunoglobulins are antibodies that the body produces to fight bacteria and viruses.  Antibodies are also responsible for allergic reactions in the body.  Immunoglobulin G is the most abundant type of antibody in the body.  It is involved in delayed hypersensitivity reactions, the most common type of allergy.  IgG antibodies do not produce anaphylactic-type allergies.  Delayed hypersensitivity reactions cause symptoms that appear anywhere from several hours to several days after exposure.  This makes IgG allergies difficult to diagnose.  Blood spot testing for IgG provides a simple and practical means for practitioners to uncover potential causes of allergic reactions and allergy related disease. 

Why have IgG test done?

• To uncover food allergies to resolve current symptoms or to prevent hidden chronic inflammation from developing into systemic disease.
• When a person is symptomatic.  There are many symptoms of delayed hypersensitivity reactions to food.  Some of the more common symptoms include:
• Digestive symptoms: abdominal bloating, abdominal pain, flatulence, diarrhea, constipation, heartburn, infant colic, canker sores
• Urinary symptoms: chronic or recurring urinary tract infections, urinary frequency or urgency, bedwetting
• Immune symptoms: frequent colds,  frequent ear infections, allergies, post-nasal drip, sinus congestion
• Mental/emotional symptoms: anxiety, depression, hyperactivity, inability to concentrate
• Musculoskeletal symptoms: muscle or joint pain,
• Respiratory symptoms:  asthma, chronic or recurring cough
• Skin symptoms: eczema, rashes, acne, hives, “allergic shiners” (aka dark circles around eyes)
• Miscellaneous symptoms: fatigue, headaches/migraines, overweight/obesity 

Who can be tested?

•  Adults and children over the age of 2 may be tested

Special Considerations:

• Antibodies are produced by the body after the ingestion of a food.  The half-life of an IgG antibody is about 3 weeks.  It takes 5 to 7 half-lives to completely eliminate a specific IgG antibody from the body.  So it could take up to 4 months for IgG levels to a reactive food to drop down to the non-reactive range.  However, to adequately prepare for the test patients should aim to eat a serving of each of the target foods at least twice in the 7 days prior to testing. 

95 Vegetarian Foods Panel