Food sensitivity is a delayed immune reaction that leads to chronic inflammation, which in turn may contribute to symptoms; food sensitivity is not a disease. Food sensitivity typically takes months to develop and is triggered by the expression of IgG antibodies. The release of IgG antibodies to specific foods is considered normal, as is the formation of antigen-antibody complexes (which form when a food antigen meets an IgG antibody and they bind together).[1]
Cells called macrophages typically remove these complexes; however, when many antigen-antibody complexes are present, macrophages may not be able to remove them all. The complexes that are left behind deposit in tissue and release substances that promote inflammation.[2]
Inflammation is much more likely to occur if the reactive food or foods remain a regular part of the diet since eventually the bodies capacity to “take out the trash” is overwhelmed, leading to inflammation and symptoms.
The good news is that the source of inflammation can be removed and with time your system can return to the status quo allowing you to re-introduce many of the reactive foods with the guidance of your healthcare provider.
Food Sensitivity Testing Misconceptions
IgG reactions, or Type III hypersensitivities, are well known in medicine, but there is some controversy as to whether immune complexes formed between IgG and food antigens can cause symptoms. Here are a few misunderstandings that often arise:
- IgG food reactions are sometimes confused with IgE food allergies. The term allergy is used exclusively for IgE food reactions, which are typically diagnosed by allergy specialists. Referring to food sensitivity as an IgG food allergy is incorrect, since no such condition exists. Only when someone has an IgE reaction to foods should the term food allergy be used and the food avoided indefinitely. An IgG reaction to food should be called food sensitivity and the foods can often be re-introduced after a period of time.
- One subtype of IgG antibodies (IgG4) helps protect against IgE food allergies. As a consequence, many allergists see IgG reactions as something positive, because this one IgG subtype may help protect against serious food allergies. However, this subtype behaves differently than the other IgG antibody subtypes. The majority of IgG antibodies (90 to 95%) form complexes with antigens (like food) that trigger inflammation, and provide no mitigation of potential IgE food allergy responses.[3]
Learn more about IgG food sensitivity testing today.