Why Test for IgG Food Antibodies and Food Sensitivity?

As it can take up to 72 hours to notice symptoms triggered by food sensitivities, culprit foods can be hard to detect using elimination diets. A food sensitivity test is therefore a helpful tool to remove the guesswork. Testing IgG responses to specific foods may help to identify problematic foods, which can then be removed or rotated in the diet for a specific period of time. This should result in a reduction of symptoms. The test works by measuring blood levels of IgG antibodies. IgG antibody formation is triggered in response to contact with specific food proteins (antigens) to which they bind together and form an immune complex. These complexes may be deposited in tissues and when formed in excess and faster than the immune system’s ability to remove them efficiently, inflammation and the development of associated symptoms may be triggered. The symptoms will depend on where in the body the complexes are deposited.

From the results of a food sensitivity test, an IgG dietary elimination programme can be designed. Removing problematic foods allows for the breakdown and elimination of existing complexes and limits the formation of new complexes to a manageable level of tolerance. Support to gut wall integrity may further improve tolerance as testing positive to a high number of foods could indicate increased intestinal permeability or “leaky gut”. The gut provides an internal barrier to the external environment and is highly selective of nutrients and pathogens absorbed into the body. If compromised, resulting permeability allows food molecules to cross into the bloodstream before they are adequately digested, potentially provoking an IgG immune mediated response. Factors contributing to a leaky gut include poor dietary choices, recreational drug use, smoking, excessive exercise, medications and stress, all of which can result in imbalance and gut dysbiosis.

To help gain the most from a food sensitivity test, particularly with a high number of elevated foods, it is important to focus on supporting the digestive system whilst following an elimination diet. Once symptoms have subsided, continued support to gut integrity may help to improve tolerance to these foods. Problematic foods may then be reintroduced as part of a healthy, balanced diet and tolerated at a reduced intake. It is important to recognise that not all food-related symptoms are caused by an IgG response; inadequate digestion, microbiome dysbiosis, candidiasis, parasites, intestinal infections, a poorly balanced diet, excessive exercise, alcohol consumption and the effects of drugs and medications may all contribute to symptoms.