Allergy Testing

Is it an Allergy or Sensitivity?

When you’re experiencing a reaction to food your immune system reacts by releasing cells called antibodies. Foods that cause antibodies to be released are called antigens or allergens. The two main types of antibodies produced in response to foods are IgE (Immunoglobin E) and IgG (Immunoglobin G). Food allergies and sensitivities differ by the type of antibody produced and the speed of the reaction.

Food Allergies  IgE Reactions — Immediate

Allergic reactions usually occur within minutes if eating a reactive food and can on rare occasions be life threatening. Skin eruptions (hives, eczema), breathing difficulties and digestive problems are common IgE reactions. Once the body has been exposed to an allergen your body remembers what it “looks like” and readily keeps a supply of IgE on hand for immediate release id it “sees” that particular allergen again. It is highly recommended that you get referred to a specialist as soon as possible if you are experiencing serious food allergies (i.e. anaphylaxis, difficulties breathing).

Food Sensitivity  IgG Reactions — Delayed

IgG reactions can take hours or days to develop — which makes it difficult to determine the exact food cause without testing. Digestive problems tend to play a major role in the development in IgG reactions. Some individuals experience “leaky guts” — which means that food particles are able to enter the bloodstream. In an IgG reaction the antibodies attach themselves to the antigen and create an antibody-antigen complex. These complexes are normally removed from the body via special cells called macrophages. However, if they are present in large amounts and the food antigen is still being consumed, the macrophages cannot remove all the complexes. These accumulate over time and are deposited in body tissues. Once in the tissue, these complexes cause inflammation, which can contribute to a variety of diseases and health conditions.

Conditions Associated with Food Sensitivities

    • Digestive Disorders — Conditions like Irritable Bowel Syndrome (IBS) and Crohn’s disease have been linked to IgG food reactions. Research has shown that elimination of IgG reactive foods can alleviate IBS symptoms.
    • Migraines — A 2007 research study found that 43 out of 65 patients who suffer from migraine headaches had complete remission of their headaches after one month of eliminating reactive foods. Another study in 2010 discovered a significant reduction in the number of headache days and migraine attacks with removal of reactive foods from patients diets.
    • Mood/attention deficit disorders — Deposition of antibody-antigen complexes in nervous system tissues may contribute to hyperactivity, depression, anxiety, inability to concentrate along with other mood disorders. There is some evidence that removal of IgG foods improves attentiveness in children.
    • Weight Gain — Antibody-antigen complexes in tissue cause inflammation, which leads to fluid retention and weight gain. To fight inflammation, the body releases a chemical called ghrelin, which is also an appetite stimulant. Therefore IgG food reactions can contribute to weight gain in two ways — fluid retention and increased appetite.

 

Why Should I Get Tested for Food Sensitivities?

Knowing what your reactive foods are is an important first step to achieving better health. In a nutshell, food sensitivities equal stress — stress slows metabolism, interferes with digestion and leads to a host of other health issues. Other reasons for testing include:

  • Sensitivities are more difficult to diagnose than allergies — testing is virtually the only way to determine which foods are responsible for the reaction.
  • Undiagnosed food sensitivities may contribute to symptoms and biochemical changes that result in illness.
  • IgG reactions frequently occur to commonly used foods such as dairy, wheat, eggs, yeast, pork and soy.
  • Elimination diets (which remove suspect foods for a period of time and then reintroduce and check for reactions) are difficult to follow and take months to complete.

Delayed Food Reactions

Delayed food reactions are IgG antibody reactions (food sensitivities) that can occur hours to days after a food is consumed. Common reactions include:

  • Systematic Reactions — Fever, fatigue, chills, sweating and feeling weak, puffiness.
  • Skin Reactions — Itching, redness, swelling, and rashes (including eczema, psoriasis).
  • Brain Reactions — Mood and memory disturbances and behavioural problems.
  • Lung Reactions — Bronchitis and asthma symptoms.
  • Musculoskeletal Reactions — Joint pain, muscle stiffness, and swelling.
  • Digestive Tract Reactions — Nausea & vomiting, diarrhoea, abdominal pain, gas, and bloating.

Eliminating Reactive Foods

Once your testing is complete and you receive your results, your family physician will help you to create a plan to eliminate the problem foods from your diet. Most people see an improvement in their symptoms within a few weeks of eliminating these foods. However it is important to understand that symptom improvement can take some time, and results vary from person to person. Removal of reactive foods can also occasionally result in withdrawal symptoms such as headaches, tiredness, irritability and hunger.

How “Leaky Gut” Contributes to Food Reactions

Leaky Gut Syndrome is caused by an inflammation in the gut lining. Inflammation can be caused by food allergies or sensitivities, abnormal gut flora, stress, certain drugs, and alcohol. An inflamed gut lining causes more food particles to leak into the bloodstream where they may come in contact with food specific immunoglobulins. A test result that shows multiple food reactions to regularly eaten foods may be an indication of leaky gut. If this is the case, your physician may suggest treatments for your digestive system in addition to making certain dietary changes.

Delayed Food Reactions

Delayed food reactions are IgG antibody reactions (food sensitivities) that can occur hours to days after a food is consumed. Common reactions include:

  • Systematic Reactions — Fever, fatigue, chills, sweating and feeling weak, puffiness.
  • Skin Reactions — Itching, redness, swelling, and rashes (including eczema, psoriasis).
  • Brain Reactions — Mood and memory disturbances and behavioural problems.
  • Lung Reactions — Bronchitis and asthma symptoms.
  • Musculoskeletal Reactions — Joint pain, muscle stiffness, and swelling.
  • Digestive Tract Reactions — Nausea & vomiting, diarrhoea, abdominal pain, gas, and bloating.

Unexpected Results

  • If you haven’t eaten a particular food in a few months, you’re less likely to have antibodies remaining in your system for that food item. In that case, a lack of reaction is most probably due to lack of exposure and doesn’t necessarily mean that the food is non-reactive.
  • Sometimes reactions appear for foods that are seldom or never eaten. For example — a child reacting to coffee. This may be due to cross-sensitivity with a related food, or may result from unintended exposure (hidden ingredients in packaged food items or sauces). High IgG may also have a role in protecting against more serious IgE reactions. It’s always important to understand that having higher than normal IgG antibodies is not a concern if the reactive food is rarely eaten.
  • Food reactions can also arise from a lack of digestive enzymes or stomach acid — chemicals naturally present in food and artificial additives. For example — lactose intolerance is due to lactase enzyme deficiency; histamine is found in wine, cheese, spinach and tomatoes; and MSG is an additive that can produce symptoms in some people. These are not immune reactions, and therefore will not result in antibody production.
  • Food reactions can also arise from previous negative experiences with a specific food (i.e. food poisoning), in that physical reactions to subsequent exposures are possible.