Both IgG and IgE blood testing are very important diagnostic tools that can provide an essential blueprint for immune system improvement.

Explaining IgE

IgE (or immunoglobulin E) allergies are immediate responses to a foreign substance that has entered the body. These foreign substances can come from food or inhalation.

IgE allergies can cause very serious symptoms like difficulty breathing, swelling, and hives. In even more severe cases IgE reactions can lead to anaphylactic shock. This test measures the blood level of IgE, one of the five subclasses of antibodies. Antibodies are proteins made by the immune system that attack antigens, such as bacteria, viruses, and allergens.

IgE antibodies are found in the lungs, skin, and mucous membranes. They are associated mainly with allergic reactions (when the immune system overreacts to environmental antigens such as pollen or pet dander) and parasitic infections.

The IgE test is often performed as part of an initial screen for allergies. Symptoms of allergies may include visible inflammation, blotches, hives, itchy eyes or nose, sneezing, nasal congestion, tight throat, and trouble breathing.

Symptoms may be seasonal (as with allergies due to pollen or molds) or year-round (as with food allergies), and they can range from mild to severe, depending on the person and the allergy. Symptoms can be particularly harsh for children as their immune systems are not fully formed yet. IgE levels may also be elevated in those with parasitic infections.

Healing the gut and immune system, and the regular elimination of parasites is crucial to cut down on all manner of immune reactions. We’ll explain more below when we get to IgG.

IgE antibodies are primarily associated with allergies. The first time someone is exposed to a foreign substance, like a virus or bacterium, it may take the immune system up to two weeks to make an antibody blueprint and to produce enough of a specific antibody to fight the infection.

A common example of a typical IgE response to a food allergy is with peanuts. Suppose a person with a peanut allergy eats a peanut. B cells in the body (a type of white blood cells that are part of your adaptive immune system) are exposed to the peanut allergens. B cells begin making IgE antibodies to fight the peanut “infection” because your body recognizes peanuts as poison, not food.

These IgE antibodies were made specifically for defending the body against peanuts. The IgE antibodies bind to the peanut molecules or allergens in the body.

After the exposure to peanuts, IgE antibodies can also attach themselves to mast cells. Mast cells are a type of white blood cell that is part of the immune and neuroimmune system. They release histamine (causing inflammation intended to keep you safe) and play a protective role in the immune system's tolerance to pathogens as well as trying to protect the blood-brain barrier.  

There in the mast cells, the IgE antibodies wait until the next peanut exposure. When this next exposure occurs exposure occurs, the IgE antibodies signal the mast cells to release histamine and other compounds. Histamine and these other compounds are the cause of allergy symptoms like itching and inflammation. All of this usually happens within minutes of ingesting the allergen, which can be pretty scary when you first determine your child has a peanut allergy!

IgE allergies are treated with medications that block the release of histamines.

Any medical doctor, functional medicine practitioner, or pediatrician should be able to run an IgE blood test to determine what your allergies are.

Keep in mind that the stronger the immune system and the healthier your gut, the better your body will be able to tolerate accidental exposure. IgE food allergies typically do not go away but can decrease over time as health improves. We recommend staying away from those things you are completely allergic to.  

Food sensitivities are a different story and often time can be overcome, and a previously damaging food (usually with the exception of a few like gluten and dairy) can become supportive and healthy again upon healing the gut lining and the immune system.

Explaining IgG

These are antibodies that provide long-term resistance to infections, called Immunoglobulin G (IgG). They have a much longer half-life (around 28 days) than the traditional IgE allergy.

This is where food sensitivities come in because they are much more subtle and most people live with them for years, if not their entire lives. A food sensitivity is an adverse reaction to a food with no antigen-antibody response.

Symptoms range from headaches and nausea to depression, anxiety, and hyperactivity, or simply just fatigue, bloating, or mood changes after eating. Dark under-eye circles when you are well-rested also indicate a negative liver response to a food, especially in children.

These symptoms may occur hours or even days after the offending food has been ingested. The degree and severity of symptoms vary widely because of the genetic makeup of the individual. Watch Christa’s show on rejuvenating the gut at the genetic level to completely understand this concept and the power you have to heal the gut and immune system by following the 5 key steps to lasting gut healing.

The complete elimination of IgG-positive foods may bring about substantial improvements in symptoms of irritable bowel syndrome*, autism, ADHD, cystic fibrosis, rheumatoid arthritis, and epilepsy as demonstrated in numerous clinical studies performed at the National Institute of Health.

Everyone should get IgG tested for food sensitivities, so they know what foods work for their body and what foods don't. It's no different than putting the right type of gas in your vehicle to help it perform the best.

Testing

An IgG food sensitivity typically checks for anywhere from 55-184 different foods and will give you reports as to how much chronic inflammation and adverse reaction particular foods cause upon consumption. It delivers results as values of high, moderate, and low.

All high and moderate values should be completely avoided for 12-16 weeks while you embark upon a proper gut-healing program. Only after you've done the work to clean up your gut and re-educate your immune system can you retest to see how many true food sensitivities are left and how you should craft your diet around them in the future. Often after gut healing, 50-80% of food sensitivities go away, and one can reintroduce certain foods, and the body will know how to best use them for health after that.

You can order your own food sensitivity tests online from ALCAT or My Med Lab. My Med Lab offers a 96 Food Panel and a 184 Food Panel. We suggest starting off small if you haven’t tested before because if you have leaky gut syndrome, then you will react to many foods that will later become non-reactive.

Leaky Gut Syndrome

There is Mucosal Barrier Assessment Saliva Test you can run by Biohealth Labs to check to see how strong or weak (thin) your gut-lining is. We suggest this test as it provides a baseline for GI health, so you know where to go with your health plan.

It looks at Secretory IgA, or SIgA. The results reveal a patient’s ability to defend against infections, allergies, and food reactions as well as provide clues as to where to go next in the investigation and treatment of health complaints.

If you have intestinal permeability or “leaky gut syndrome,” this means there are microscopic holes in the lining of your small intestine (where food gets absorbed) allowing food particles, toxins, & bacteria to escape (think of a brick wall with holes in the caulking or mortar) into the bloodstream. Just a few years of stress, several rounds of antibiotics, or frequent soda, coffee, alcohol, and sugar consumption can thin the lining of the gut.

When food particles escape the gut lining, the spleen, which is a major immune organ, has to work overtime to clear them out of the bloodstream because they do not belong there. This puts an inordinate burden on your immune function (and invariably some of those toxins make their way to your brain).  Chronic, prolonged inflammation and toxicity over time can be a leading cause of autoimmune disease and related disorders.

If you’d like to learn more about digestive health, watch our related shows:

Digestive and Immune Supplements 101
5 Steps to Heal The Gut  & Immune System
Is Gluten Really That Bad for You?
How to Balance Stomach Acid and Overcome Heartburn
Kick Candida for Good

REFERENCES

https://www.ncbi.nlm.nih.gov/books/NBK27117/
https://www.khanacademy.org/science/biology/human-biology/immunology/v/b-lymphocytes-b-cells
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1774223/