Food sensitivity (Type II hypersensitivity- IgG) is not the same as food allergy (Type I hypersensitivity- IgE), which is an immediate reaction and can be severe- potentially leading to anaphylaxis. It is also not the same as Celiac disease, which is a serious autoimmune reaction to the gliadin protein, which is found in gluten-containing grains (i.e. wheat, spelt, barley, rye and oats that have been cross-contaminated during processing).
Intolerance to a food is typically the result of a enzyme deficiency. The most common example being lactose intolerance where consuming milk and dairy products will result in tummy aches, gas, bloating and diarrhea. This happens because your body does not make enough lactase enzyme to properly digest lactose, leading to painful and awkward digestive symptoms. Lactose intolerance is determined by genetics and can be managed by having a lactase pill when consuming dairy products. This condition is usually dose-dependent (i.e. the more ice cream you eat- the worse your gas and bloating will be).
Food sensitivity involves the creation of an IgG antibody (Ab) to food antigens (Ag), with the Ab attaching itself to the food Ag and creating an Ab-Ag “complex”. The generation of antibodies is a normal immune system function and is meant to be a protective or helpful signal, but when the system is overloaded or dysfunctional (due to various reasons), the excessive production or inadequate clearance will contribute to chronic inflammation and a lot of health issues.
The tricky thing about food sensitivity reactions is that their effects may not be limited to the digestive system, nor are the effects limited to the time period occurring immediately after consumption of the food(s). Besides digestive discomfort and irritable bowel syndrome-type symptoms, the effects of food sensitivities can also appear as skin irritation, headaches and migraines, fatigue and brain fog and can occur up to 72 hours AFTER consuming the offending food(s). This can make it very challenging to determine the problematic foods.
Causes of food sensitivity may include consuming foods that are
not ideal for your genetic makeup, poor food choices (i.e. processed foods
containing a lot of additives, fillers, preservatives, etc.), poor digestion (i.e.
low stomach acid, use of medications that inhibit stomach acid production, etc.)
and increased gut permeability.
Poor digestion coupled with increased gut permeability leads to the unchecked passage of incompletely digested food across into the blood stream (more on this in a future post), leading to local and systemic inflammation. Food sensitivity reactions can also make it difficult to lose those few extra pounds and may contribute to worsening of auto-immune conditions.
Testing for IgG food sensitivity is done with a blood test. The IgG responses to a panel of different foods is measured by the lab and a detailed report provides an interpretation of the IgG response to different foods. This will give you an idea of where to start when looking at diet changes to improve your health. This test can be ordered by your Naturopathic Doctor, and they will go over the results with you, including recommendations such as duration of the diet changes, what to observe during this time period, what to expect and when to reassess or re-test (if needed).
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