Food Allergy or Food Sensitivity
In a food reaction, the immune system reacts by releasing cells called antibodies. Foods that cause antibodies to be released are called antigens or allergens. Two types of antibodies commonly produced in response to foods are IgE (immunoglobulin E) and IgG (immunoglobulin G). Food allergies and food sensitivities differ by the type of antibody produced and the speed of the reaction. Food allergy is an immediate reaction caused by the production of IgE antibodies, while food sensitivity is a delayed reaction caused by the production of IgG antibodies to specific foods.
Food Allergy IgE Reations – Immediate
IgE reactions generally occur within minutes of eating a reactive food and can, on rare occasions, be life-threatening (e.g. peanut allergies). Skin eruptions (hives, eczema), breathing and digestive problems are also common IgE reactions. After first time exposure to an allergen, the body remembers what the allergen “looks like” and keeps a supply of IgE ready for immediate release if it “sees” that allergen again. Referral to a specialist is recommended in the case of serious food allergies (i.e. difficulty breathing, anaphylaxis).
Food Sensitivity IgG Reations – Delayed
IgG reactions take hours or days to develop, making it difficult to determine the food cause without testing. In an IgG reaction, the IgG antibodies attach themselves to the antigen and create an antibody-antigen complex. These complexes are normally removed by special cells called macrophages. However, if they are present in large numbers and the food antigen is still being consumed, the macrophages are unable to remove all the complexes. The antigen-antibody complexes accumulate and are deposited in body tissues. Once in 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 43/65 patients with migraine headaches had complete remission of headaches after one month of eliminating reactive foods. Another study in 2010 found a significant reduction in the number of headache days and migraine attacks with elimination of reactive foods.
Mood/attention deficit disorders: Deposition of antibody-antigen complexes in nervous system tissues may contribute to hyperactivity, depression, anxiety, inability to concentrate and other mood disorders. There is some evidence that eliminating IgG food antigens 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 also happens to be an appetite stimulant. Thus, IgG food reactions may contribute to weight gain in two ways: fluid retention and increased appetite.
Why Test Food Sensitivities
- Because hours or days can pass between the time a reactive food is consumed and the occurrence of a reaction occurs, testing is virtually the only way to determine which foods are responsible for the reaction.
- IgG reactions frequently occur to commonly consumed foods such as dairy, wheat, eggs, yeast, pork and soy.
- Elimination diets (remove suspect foods for a period of time and then reintroduce and check for reactions) are difficult to follow and can take months to complete.
A sample RMA FST™ report appears at right. Foods with green boxes next to them are considered normal, or non-reactive, while foods with orange boxes are borderline, or close to being reactive. The red shaded box food results are considered reactive. Thus, it is easy to see at a glance which foods are problematic for you. The RMA FST™ also lists results by reactivity, so that all your reactive foods are grouped together. Knowing which foods you react to is an important first step to achieving better health.
Eliminating Reactive Foods
A sample RMA FST™ report appears at right. Foods with green boxes next to them are considered normal, or non-reactive, while foods with orange boxes are borderline, or close to being reactive. The red shaded box food results are considered reactive. Thus, it is easy to see at a glance which foods are problematic for you. The RMA FST™ also lists results by reactivity, so that all your reactive foods are grouped together. Knowing which foods you react to is an important first step to achieving better health. Your healthcare professional is best qualified to help you interpret the meaning of your results.
How “Leaky Gut” Contributes to Food Reactions
Leaky gut syndrome is caused by 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. Therefore, a test report that shows multiple food reactions to foods regularly eaten may be an indication of leaky gut. If so, your healthcare professional may suggest treatments for your digestive system in addition to dietary changes.
- If you have not eaten a particular food for many months, you less likely to have antibodies to that food still. In that case, a lack of reaction is most probably due to lack of exposure and does not necessarily mean the food is non-reactive.
- Sometimes reactions appear for foods 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 inadvertent exposure to that food (hidden ingredient in packaged food item or sauce). Elevated IgG may also have a role in protecting against more serious IgE reactions. It’s important to understand that having elevated IgG antibodies is not a concern if the reactive food is rarely eaten.
- Non-immune food reactions: 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 (e.g. food poisoning), in that physical reactions to subsequent exposures are possible.
Delayed Food Reactions
Delayed Food reactions are IgG antibody reactions (food sensitivities) that occur hours to days after a food is consumed. The inflammatory chemicals released with antibody-antigen complexes may have the following effects:
Fever, fatigue, chills, sweating and feeling weak, puffiness.
Itching, redness, swelling, and rashes (including eczema, psoriasis).
Mood and memory disturbances and behavioural problems.
Bronchitis and asthma symptoms.
Joint pain, muscle stiffness and swelling.
Nausea & vomiting, diarrhea, abdominal pain, gas, and bloating.
Good health has a lot to do with maintaining balance; the right balance of work and play, the right balance of nutrients in the diet, and the right kinds of foods.
Undiagnosed food sensitivities may contribute to symptoms and biochemical changes that result in illness.
Firstline is committed to offering tests that identify food reactions and other imbalances – so they can be corrected before disease develops!
Information is for educational purposes only. It is not meant as medical advice and any treatment decisions should be made with the knowledge or consent of your healthcare professional.